This is a plant room of a Viessmann Vitocal 150A 8kW unit installation in Guildford. Artykuł Viessmann Vitocal 150A 8kW pochodzi z serwisu Urban Plumbers Ltd..
This is a plant room of a Viessmann Vitocal 150A 8kW unit installation in Guildford. <img fetchpriority="high" decoding="async" width="1024" height="576" data-id="1611" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/09/IMG_1732.jpg" alt="" class="wp-image-1611" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/09/IMG_1732.jpg 1024w, https://www.urbanplumbers.co.uk/wp-content/uploads/2025/09/IMG_1732-1000x563.jpg 1000w" sizes="(max-width: 1024px) 100vw, 1024px" /> Artykuł Viessmann Vitocal 150A 8kW pochodzi z serwisu Urban Plumbers Ltd..
Design Files for Vaillant Arotherm Heat Pump Installation
Below, you will find my design files and calculations for the installation of a Vaillant Arotherm Plus heat pump that you can see in my YouTube video: “Design Heating System Like A Pro” Artykuł Design Files for Vaillant Arotherm Heat Pump Installation pochodzi z serwisu Urban Plumbers Ltd..
Below, you will find my design files and calculations for the installation of a Vaillant Arotherm Plus heat pump that you can see in my YouTube video: “Design Heating System Like A Pro” <img decoding="async" class="alignnone wp-image-1423 size-medium" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/ground-floor-1024x576.png-1000x563.webp" alt="" width="1000" height="563" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/ground-floor-1024x576.png-1000x563.webp 1000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/ground-floor-1024x576.png.webp 1024w" sizes="(max-width: 1000px) 100vw, 1000px" /> <img loading="lazy" decoding="async" class="alignnone wp-image-1429 size-medium" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/first-floor-2-1000x667.webp" alt="" width="1000" height="667" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/first-floor-2-1000x667.webp 1000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2025/01/first-floor-2.webp 1400w" sizes="auto, (max-width: 1000px) 100vw, 1000px" /> Artykuł Design Files for Vaillant Arotherm Heat Pump Installation pochodzi z serwisu Urban Plumbers Ltd..
Vaillant Eco Tec Plus system boiler hot water priority diagrams
Below, you will find my design files and calculations for the installation of a Vaillant Arotherm Plus heat pump that you can see in my YouTube video: “Design Heating System Like A Pro” Artykuł Vaillant Eco Tec Plus system boiler hot water priority diagrams pochodzi z serwisu Urban Plumbers Ltd..
This are diagrams for domestic hot hot water priority set up using: – Vaillant system boilers – Vaillant SensoComfort controls with VR 71 wiring ceters – System with hot water cylinder, radiators and UFH <img loading="lazy" decoding="async" class="alignnone wp-image-1439 size-medium" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-1000x750.webp" alt="" width="1000" height="750" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-1000x750.webp 1000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-2000x1500.webp 2000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics.webp 2048w" sizes="auto, (max-width: 1000px) 100vw, 1000px" /> <img loading="lazy" decoding="async" class="alignnone wp-image-1440 size-medium" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-controls-copy-1000x750.webp" alt="" width="1000" height="750" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-controls-copy-1000x750.webp 1000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-controls-copy-2000x1500.webp 2000w, https://www.urbanplumbers.co.uk/wp-content/uploads/2022/11/vaillant-schematics-controls-copy.webp 2048w" sizes="auto, (max-width: 1000px) 100vw, 1000px" /> Artykuł Vaillant Eco Tec Plus system boiler hot water priority diagrams pochodzi z serwisu Urban Plumbers Ltd..
Vaillant F.75 error code – full boiler repair
Below, you will find my design files and calculations for the installation of a Vaillant Arotherm Plus heat pump that you can see in my YouTube video: “Design Heating System Like A Pro” Artykuł Vaillant F.75 error code – full boiler repair pochodzi z serwisu Urban Plumbers Ltd..
This Vaillant boiler has been suffering from error codes F.75 and low pressure on the pressure gauge. There was also a visible leak to the right-hand side of the boiler. When I opened the boiler, I found a source of the leak – it as scaled Automatic Air Vent on the boiler pump. First call of action was to replace that leaking AAV. Below you can see an existing leaking part on the left and a new part on the right. With the boiler drained down, I also checked the expansion vessel pressure – it was zero. I repressurized the expansion vessel to 0.9 bar. I also replaced the Pressure Relief Valve – as with a flat expansion vessel, those valves usually pass as well. New PRV pictured below. With the boiler fully drained down, the pressure sensor should be sensing no pressure and the expected error message on the boiler display is usually F.22 or 0.0bar – or both messages flashing one after another. However, in this case the boiler was showing an F.75 error message. What do those error messages mean? F.22 – low water pressure, boiler will not fire. Top up boiler pressure or find a leak and repair the leak on the system or on the boiler itself F.75 – no pressure increase detected when the pump starts. This prevents the boiler from firing as the PCB assumes that the pump is not working. This error according to the Vaillant manual should point to the faulty pump. In most cases however, this is a faulty or blocked pressure sensor – as those little sensors are notoriously unreliable. The pumps on those boilers are very reliable and fail very rarely. Boiler below showing error code F.75 with no pressure in the boiler. Expected error code in this case should be F.22 / o.o bar. On the picture below, you can see the faulty pressure sensor in situ. It is this black round object with a white connector and black and red wires attached to it. I removed the sensor (member the boiler needs to be drained down), and as you can see from the picture below it is fully blocked. I do not recommend trying to unblock those sensors. Always replace them with a new sensor. I fitted the new sensor, and turn the boiler on, still with no pressure in the boiler. Now the boiler started showing correct message for the low pressure – F.22 alternating with 0.0bar. This means that the pressure sensor is operating correctly. It was time to repressurize the boiler to 1 bar and make sure there are no more leaks. This concluded the repair. I also recommended that the system is power flushed, as dirt in the system blocked the pressure sensor and also caused a leak on the pump AAV. Parts replaced on this repair: – pressure sensor – auto air vent – pressure relief valve – expansion vessel repressurized Artykuł Vaillant F.75 error code – full boiler repair pochodzi z serwisu Urban Plumbers Ltd..
Ideal Logic intermittent ‘ignition lockout’ message, L2 boiler fault, error code
Below, you will find my design files and calculations for the installation of a Vaillant Arotherm Plus heat pump that you can see in my YouTube video: “Design Heating System Like A Pro” Artykuł Ideal Logic intermittent ‘ignition lockout’ message, L2 boiler fault, error code pochodzi z serwisu Urban Plumbers Ltd..
Ideal Logic combi boiler is one of the most popular combination boilers installed in the UK today. There are thousands of those boilers installed in homes in the UK. One of the most common errors on these boilers is: Ignition Lockout / L2 error code – Ideal Logic / Ideal Independent / Ideal Classic Depending on the version of this boiler, the same error can be displayed as ‘ignition lockout’ on Logics + and Logic Max versions or simply as an L2 error on Ideal Independent, Ideal Atlantic & Ideal Classic 2 boilers. This error can be simply caused by the lack of gas, so before calling a boiler engineer out it is worth checking if other gas appliances are getting gas, if your prepaid meter is in credit or if the gas is on. Most of the time this error can be simply re set by resetting the boiler. On Ideal Logics, you simply turn the far-right dial to the right and hold it there for a few seconds. This should clear the error and allow you to use the boiler, as those errors are usually intermittent. It will still need a competent boiler engineer to have a look at the boiler and find the underlaying cause of those intermittent faults. In my experience, there are a number of causes for this fault. The most common faulty part is the ignition module also called spark generator. If your Ideal boiler suffers from intermittent ‘ignition faults’ or L2 error codes, you can get in touch with me to get it repaired. Just click the link below to go to my website home page: Ideal boilers servicing and repair Below, you can read about a real life Ideal Logic repair. This particular boiler was installed in 2011 (It is 10 years old today) and it was suffering from intermittent ignition lock outs. When I removed the front case I could see that there were two obvious problems with the boiler. These were most likely unrelated to the ignition lock outs, but had to be addressed first. The boiler sump was cracked and needed replacing. The tell-tale signs of a cracked sump is a white residue around the screw of the sump cover plate. Those sumps always crack in the same place. Ideal claims they crack due to excessive force when screwing the cover plate, but I have seen them cracked for no obvious reason on boilers that have never had the cover plate removed. Here you can see a close up of the hairline crack on the sump inside. It is a very common problem with these boilers. The crack is on the bottom right hand side. It is more obvious on the second picture. This was taken after I removed the sump. Now the hairline crack is visible on the top left. Now it was time to fit a new sump. New sump and sump cover picture below. This is the old sump. Removing the sump without having to take out the main heat exchanger is possible, but not the easiest of jobs. You have to break the old sump a bit to get it out. New sump fitted to the boiler. <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7308-768x1024.jpg.webp" alt="" class="wp-image-1460" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7308-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7308-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> Now it was time to address the second obvious problem with this boiler. It has a completely blocked condensate trap. This could have caused intermittent ignition lock outs on its own. Luckily it is quite simple to clear those traps out. Blocked trap on a picture below. After cleaning the trap, I replaced the ignition module, as they can be intermittently faulty. I also removed the burner and replaced the main heat exchanger gasket, as the old one was worn. The ignition and sensing electrodes still looked fine, so I left those in place. I also cleaned fan injector and venturi, as if those are not spotless they can throw some ignition problems as well. I reassembled the boiler. <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7312-768x1024.jpg.webp" alt="" class="wp-image-1465" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7312-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7312-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> It was time to test it. I run combustion analysis on low and high rate. The boiler seems to operate fine. However, I will have to wait for feedback from tenants to see if the intermittent lock out does not happen again, as unfortunately it is one of those faults that is very difficult to test for. <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7328-768x1024.jpg.webp" alt="" class="wp-image-1466" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7328-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7328-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> Below you can see the boiler happily firing, no more leaks on a sump, no ignition lock outs or errors when tested on site. If you need your Ideal boiler serviced or repaired please contact me through this website. Artykuł Ideal Logic intermittent ‘ignition lockout’ message, L2 boiler fault, error code pochodzi z serwisu Urban Plumbers Ltd..
Vaillant Eco Tec R1 combi boiler repair Brixton, Vaillant F22, F75 error code.
Hi, I am Simon and I repair all models of Vaillant boilers. I am based in Upper Norwood & serve South London area. If your boiler suffers from F.22 or F.75 errors, or any other Vaillant error codes, please get in touch with me here: Vaillant Repairs Crystal Palace Vaillant Eco Tec Pro R1 – […] Artykuł Vaillant Eco Tec R1 combi boiler repair Brixton, Vaillant F22, F75 error code. pochodzi z serwisu Urban Plumbers Ltd..
Hi, I am Simon and I repair all models of Vaillant boilers. I am based in Upper Norwood & serve South London area. If your boiler suffers from F.22 or F.75 errors, or any other Vaillant error codes, please get in touch with me here: Vaillant Repairs Crystal Palace Vaillant Eco Tec Pro R1 – manufactured in 2007. This hugely popular boiler has been suffering from the following problems: • hot water not reliable – stops working occasionally • heating not reliable – sometimes works, but not always • boiler needs resetting to get it to work again When I took the case off I noticed that: • this early version of Vaillant Eco Tec still had rubber hoses on return • pressure gauge was at zero, but the boiler was still working – I assumed that the pressure sensor must be blocked • I removed pressure relief connection – it was wet – pressure relief valve was leaking • I checked the expansion vessel – it was flat and full of water. I also notice that expansion vessel looked like it was recently replaced • there was no thermostat or any controls connected to the boiler, meaning that heating was always on This Vaillant boiler have had the heating always on for last 14 years and the way it was controlled was by turning all radiator valves off in the summer. This caused the boiler to constantly turn itself on and off when all the radiators were of – so-called cycling, the best way to flatten your expansion vessel, activate the pressure relief valve and eventually corrode the system and destroy the boiler in the process. How has this boiler survived all this time in this set up is beyond me. The work that I have done is as follows: • replace the infamous rubber hose on the return pipework with a new rubber hose. I did not have the upgrade kit with that replaces hoses with copper connection with me and this was a short-term solution to some of this boiler problems. The problem with rubber hoses is the fact that they accumulate system dirt causing blockage to boiler components such as: main heat exchanger, pressure sensor, pressure gauge, etc. You can see the original rubber hose above the pump in the picture below. I removed that hose, below you can see how much ‘crud’ it had accumulated. <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7226-768x1024.jpg.webp" alt="" class="wp-image-1472" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7226-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7226-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7218-768x1024.jpg.webp" alt="" class="wp-image-1474" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7218-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7218-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> New rubber hose got installed. I usually keep them as van stock, as there are still some of the early Vaillant Eco Tec R1 out there with those hoses. I do not think it makes sense to upgrade the boiler to copper connection at this stage, the boiler is 14 years old and if the hoses start creating problems again it will be new boiler time. Below, you can see the return connection with hose removed and new hose installed. With new hose installed, it was time to replace the blocked pressure sensor. Actually I was quite surprised that the boiler was working with a blocked sensor and flat expansion vessel, as this usually causes an F.75 error – no change of pressure detected at pump start. Since those pressure sensors are very unreliable and also a van stock and a relatively cheap components, I decided to replace it anyway. <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7230-768x1024.jpg.webp" alt="" class="wp-image-1477" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7230-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7230-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> Now the boiler finally was showing error F.22 – low pressure with no water and was not starting, as it was before – with no water in the system. I have also pumped the expansion vessel to 0.8 bar as it was completely flat. No surprise here, any expansion vessel will go flat in no time if the boiler is constantly cycling forever. I tried to pressurize the system and quickly noticed that the pressure gauge was not moving. Another component was faulty! The pressure gauge was blocked. I managed to find a new pressure gauge in the van. This job was quickly depleting my Vaillant spare parts box in my Van! <img loading="lazy" decoding="async" width="768" height="1024" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7250-768x1024.jpg.webp" alt="" class="wp-image-1480" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7250-768x1024.jpg.webp 768w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/10/IMG_7250-768x1024.jpg-750x1000.webp 750w" sizes="auto, (max-width: 768px) 100vw, 768px" /> The boiler got rained again. I quickly changed the pressure gauge and pressurized the boiler. Now we were getting somewhere. The boiler pressure gauge was showing correct pressure, pressure sensor was reading correct pressure, expansion vessel was topped up, flexible hoses, that caused those blockages were replaced. I also checked a ‘canoe filter’ and cleaned it when changing the pressure sensor. Canoe filter is a canoe shaped filter (hence the nick name) located before the flow goes into the plate heat exchanger, to protect the plate heat exchanger from blocking. I must say that I almost never see plate heat exchanger block on Vaillant Eco Tec boilers. It does the job, that little filter. Below the boiler in question after all repairs. After I installed the case back on, I noticed the little sticker by the pressure gauge. Instead of replacing the pressure gauge, someone just put a sticker that read: ‘ auge takes 24h to reflect pressure changes’. I can only assume a money pinching landlord put that sticker there instead of calling a plumber to repair the boiler. A gauge that does not show changes in pressure immediately may as well not be there. What a waste of time that sticker was and a great way to destroy your boiler, Sir or Madam! Do not do that again, please. After managing to find all those spare parts in my van, there was one very important part I actually did not have, a thermostat. I booked another visit on this job to: • supply and install new RF thermostat to save the boiler from constant cycling • fully service the boiler – open up that combustion chamber and clean it, check combustion and adjust it if required • Tee into flow and return and flush the boiler with my power flushing machine as there is still a slight blockage on main heat exchanger as boiler gets a bit too wide difference between flow and return on low rate – delta T gets a bit too wide and boiler cycles on hot water and heating, although it is not immediately obvious, as hot water temperature is retalively constant to the end user That is a lot of work required to save a 14 years old boiler, and I am actually amazed it is still going, as this poor Vaillant Eco Tec Pro R1 has had a hard life of constant overheating and cycling. Artykuł Vaillant Eco Tec R1 combi boiler repair Brixton, Vaillant F22, F75 error code. pochodzi z serwisu Urban Plumbers Ltd..
How efficient are modern condensing boilers?
Today I am going to show you how you can save money on your central heating and hot water gas bills. Yes – we are talking about system efficiency or actually rather we are talking about why most gas boilers are notoriously inefficient. If you apply principles discussed in this blog you will not only […] Artykuł How efficient are modern condensing boilers? pochodzi z serwisu Urban Plumbers Ltd..
Today I am going to show you how you can save money on your central heating and hot water gas bills. Yes – we are talking about system efficiency or actually rather we are talking about why most gas boilers are notoriously inefficient. If you apply principles discussed in this blog you will not only be able to save yourself few hundred pounds a year but you will also learn how to run your system in a way that will prevent your boilers from breakdowns and costly repairs. “What? Systems that runs efficiently prevent boilers from breaking down? What kind of voodoo is he talking about?” Well, as you will see there is a correlation between inefficient systems and longevity of your boiler and system components – but we will get to that. EFFICIENCY What is efficiency? Firstly we need to distinguish between following aspect of efficiency: – your house energy efficiency – it basically means how quickly your house is losing heat – we call it a heat loss and we calculate a specific value for each property. The lower the value measured in kWH to better the efficiency of the property – your heat generator efficiency – this is a gas boiler in our example, but it could also be a heat pump, electric boiler or an oil boiler. The efficiency of a gas boiler is simply the difference between energy we put in in form of gas and usable heat output we receive to heat our homes. In case of gas boilers there is always some heat lost through the flue as products of combustion HOW TO GET MORE FROM YOUR GAS BOILER General rule of thumb when it comes to gas boiler efficiency is: the lower your boiler return pipework temperature the higher your system efficiency all other things being equal. Your gas boiler has a pipe called flow – this is where hot water enters your system on its way from the heat exchanger to the radiators or other heat emitters. That hot water losses it’s heat or energy being dissipated through radiators and then comes back cooler to the boiler through a pipe called Return to be heated again. <img loading="lazy" decoding="async" width="1024" height="680" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/flow_return-1024x680.jpg.webp" alt="" class="wp-image-1486" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/flow_return-1024x680.jpg.webp 1024w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/flow_return-1024x680.jpg-1000x664.webp 1000w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /> On modern condensing boilers we try to design the systems in a way that the difference between the flow and return in around 20 degrees. We call it DT 20. For example – if you take your average boiler out of the box it will be most likely set to 75 degrees flow giving a theoretical 55 degrees return. The lower we can get the return pipework temperature the higher your boiler efficiency. This graph illustrates this principle. <img loading="lazy" decoding="async" width="1024" height="576" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/efficiency-graph-1-1024x576.jpg.webp" alt="" class="wp-image-1487" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/efficiency-graph-1-1024x576.jpg.webp 1024w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/efficiency-graph-1-1024x576.jpg-1000x563.webp 1000w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /> As you can see there is a big jump in efficiency from around 86% when the return temperature drops below 54 degrees. This is what is called a dew point or condensing mode. At around 54 degrees return we enter a condensing mode at around 88% efficiency. But if we look at the graph we can also see that there is a theoretical 97% efficiency possible. The only trouble is the return temperature would have to drop to areound 20 degrees. As you can also see on this graph there is a sudden jump in efficiency once we go below 54 degrees of boiler return. This is because products of combustion change it’s state form gas into steam. We call this change a ‘phase change’ and it releases larger amounts of energy that we call latent heat. Latent heat: the energy required to transition one unit of a substance from solid to liquid; equivalently, the energy liberated when one unit of a substance transitions from liquid to solid. Realistically we can run gas fired boilers at 30 degrees return pipework with 94-95% efficiency. Wet underfloor heating is one of the ways we can achieve those high efficiencies. We could also oversize radiators to be able to run the system at lower return temperatures. Hopefully by know you start to understand that it is not the make of the boiler that will make your system more efficient. The way it is set up and run in much more important. Since now we understand modern condensing gas boiler efficiency and we know that we want to run the boiler at the lowest possible temperatures to achieve higher efficiency, what are the practical steps we can take to make sure that our gas fired central heating is super efficient? HEAT LOSS Heat loss of your home is where it all starts from. It is basically the speed at which the building looses heat. Heat loss calculations are based on many factors – but for our purposes the most important is the fact that the figure is based on a fixed external temperature, usually around -2 degrees. What we have to remember is the fact that this is assumed worst case scenario and that most of the year the external temperatures will be higher than -2. What does it mean for our central heating and our boiler? Well, it means that most of the time our radiators and the boiler will be oversized. It also means that most of the time it will be perfectly fine to run for boiler at a fraction of it’s output and also at lower temperatures giving us more efficiency and savings. To illustrate this idea I have borrowed a table from Kimbo from ‘Heating Academy in Northampton’ – Kimbo runs excellent heating and hydroponics courses for installers and I highly recommend his training to anyone in the heating industry. <img loading="lazy" decoding="async" width="1024" height="576" src="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/Heat-loss-vs-external-temp-1024x576.jpg.webp" alt="" class="wp-image-1488" srcset="https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/Heat-loss-vs-external-temp-1024x576.jpg.webp 1024w, https://www.urbanplumbers.co.uk/wp-content/uploads/2021/09/Heat-loss-vs-external-temp-1024x576.jpg-1000x563.webp 1000w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /> This shows a relation between the heat loss calculated at -2 degrees and how it changes with the rise of external temperature. In this example we have 8Kw at -2. As you can see at 10 degrees we will only need 4kW. PRACTICAL STEPS FOR HIGHER EFFICIENCY 1. Boiler sizing Now we understand the relation between the boiler return temperature and boiler efficiency. We also know that the warmer the weather the lower boiler output we need. The question is therfore: what is the most efficiecnt way we should heat our homes? Should you have a big boiler that can blast loads of heat and bring the property to nice comfort levels of temprature or maybe it is better to have a low output boiler that stays on for much longer periods simply maintaning the heat lost to the colder outside? There is a number of problems with running your boiler flat out or with having and oversized boiler for your needs. As a matter of fact vast majority of gas boilers installed in UK are oversized. Keep in mind that the average heating requirement for a property in the UK is around 8kW. Or to put it differently 80% of UK housing stock requires less than 8kW heating. Boilers have fixed modulation ratios. It means they can only modulate so low. There are notable exceptions of large boilers that can modulate very low but those are not very common. If you choose your boiler next time, remember – bigger is not always better. So what happens when we oversize the boiler you ask? Well, the boiler will not be able to modulate down to let’s say 4kW when it is 10 degrees outside and it will reach the set point very quickly and then it will shut down and wait to cool down. Then the process will start again, boiler will overheat and it will cycle on forever. This creates a situation when the boiler is no longer working efficiently. It also puts undue strain on the boiler components as they start and stop more often. It also puts additional stress on the heat exchanger due to thermal expansion and contraction. In the end your boiler will have much short life span and will never be as efficient as it could be if it was sized correctly. The advice here is: size your boiler correctly to the system and pay special attention to how low the boiler can modulate down. The lower the better and it will not only save you money on your heating bills, it will also keep the boiler components from falling prematurely 2. Weather compensation Remember when I said that you could save money by running your boiler at lower temperatures? But what happened if it gets really cold outside and you forget to change the setting to higher ones? Or the weather gets warmer and you forget to lower your boiler settings? This is where weather compensation comes in. It is a little sensor that will cost you around £20-£30. What it does is pretty simple – it gives the external temperature reading to the boiler and the flow temperature gets adjusted automatically so you don’t have to remember to change settings when the temperature outside changes. Weather compensation is probably the cheapest and quickest way to save you biggest amounts of money on your heating bills. This can be used on combi, system and heat only boilers. 3. Do not install S & Y plans – use Domestic Hot Water Priority instead Weather compensation and low temperature heating creates a problems on antiquated heating systems such as S and Y plans. On those systems the boiler does not know if it is doing heating or hot water. If you put weather compensation on those systems you may struggle to get hot water up to the required temperature. The answer to this problem is stopping installation of S and Y plan systems or conversion of existing systems into what is called a domrstic hot water priority system – DHWP . In those systems the boiler uses weather comp for central heating but it switches to a different output for heating water in the hot water cylinder. Also, hot water takes priority over heating and central heating does not turn on till hot water is satisfied. If you are getting a new system boiler fittedit may be worth looking for a boiler that can operate in domestic hot water priority mode (DHWP). There is a number of boilers that support DHWP from brands such as Viessman, Intergas, Vaillant and Ideal. The key here is the ability of the boiler to fire at 2 different rates – one for central heating and one for domestic hot water. 4. Stop using on / off controls A traditional thermostat only acts as a on / off switch and we still see loads of them being fitted. Modern controls offer us what is called Load Compensation. It is usually done through a communication protocol such as Open Therm or eBus on Vaillant. What those controls do is they send internal temperature to the boiler, compare it to set temperature on the thermostat and choose to fire at different rates depending on the gap between internal temperature and the set point. The bigger the gap between those points the higher the rate the boiler will fire. This gives us extra efficiency and helps to stop the boiler from cycling. The tip here is: when you choose your next boiler make sure that it is compatible with load compensating controls. I choose to use Intergas boilers as they are fully compatible with OT controls. 5. Range rate your boiler, oversize your radiators Most boilers that I come across in the wild are almost never set up to the system. Those boilers should have been range rated – meaning they should have been adjusted to match the property heat loss at around -2 degrees outside, also know as the worst case scenario. Although there is a requirement to fit efficient condensing boilers, there is no requirement to actually making sure that they operate efficiently once installed. With heat pumps becoming more popular there is a lot of talk about low temperature heating. We already know that low temperature heating so more efficient, but how is it achieved on condensing gas boilers? It is achieved by calculating the size of your radiators based on lower flow temperatures. Traditionally radiators are tested with the difference between average radiator temperature and room temperature of 50 degrees. But if we want to run our flow around 60 degrees and return at around 40 we will have to design the system with the difference between average radiator temperature and room temperature of around 30 degrees. This means we will have to apply correction factor to the radiators and get much larger radiators. Good news is – your will be future proofing your property for low temperature appliances such as heat pumps and also saving a bit on your gas bill when using your gas boiler. Saving energy is only one of the bonuses of low temperature heating. Low system temperature also prevents corrosion as the higher the system temperature the the faster the corrosion process. Low temperatures also extend the life of the boiler and your system components by putting less strain on them. I have noticed that expansion vessels for example last much longer on systems that are comissioned correctly and run at lower temperatures. CONCLUSION I hope you now start to see the benefits of having an efficient heating system. Now go to your boiler and see what flow setting it is on. If it is at 75 degrees or higher try setting it at 60 or even lower. If you are serious about saving fuel and money – get a weather compensator – it will pay for itself very quickly. If you want extra efficiency – upgrade your radiators to bigger sizes, install load compensating controls and if you have a hot water cylinder and a boiler than can support DHWP – consider converting your S or Y plan into a How Water Priority System. If you would like to see an efficient installation with DHWP I got a video from one of my installations here. Watch it to see a Hot Water Priority installation: Hot Water Priority Boiler Installation Video If you would like a quote for a super efficiecnt central heating & hot water installation you can contact me here: super efficient condesing boiler installation quote Artykuł How efficient are modern condensing boilers? pochodzi z serwisu Urban Plumbers Ltd..
Emergency boiler repair in Crystal Palace, SE19
I got called to diagnose and repair a suspected boiler leak in SE19, Crystal Palace. The client actually used the phrase ‘Plumber to fix a leaking boiler in SE19’ to find me on Google. When I got to site, I was met with this massive leak coming from the boiler pressure relief valve that has soaked the whole […] Artykuł Emergency boiler repair in Crystal Palace, SE19 pochodzi z serwisu Urban Plumbers Ltd..
I got called to diagnose and repair a suspected boiler leak in SE19, Crystal Palace. The client actually used the phrase ‘Plumber to fix a leaking boiler in SE19’ to find me on Google. When I got to site, I was met with this massive leak coming from the boiler pressure relief valve that has soaked the whole wall. I quickly noticed that the filling loop was passing and over pressurizing the central heating system, causing a continuous leak of hot water. On top of that the pressure relief pipework was going uphill making water drip on to the pipe and into the wall. On quick examination, I also found something rather strange. The magnetic filter was fitted with a bypass (the filter was not really doing much) and on top of that one of the soldered joints was leaking. Generally, the installation was really shoddy. When I asked the client when it was installed, it turned out that it was done only 3 years ago. Also, the boiler was a direct swap and the client paid £2600 for supply and fit of a budget boiler. Something wasn’t quote right. I checked paperwork and a quick Google search of the full name of the installer came back with BBC rouge traders article. It may be a good idea to google your installer if you are looking to have your boiler replaced! That could have saved a lot of grief in this case. Coming back to the repair, what has been done to remedy the situation: replace pressure relief valve re pressurize expansion vessel replace filling loop with a compliant filling loop with 2 stop taps remove filter by pass and at the same time repair leak to the pipework change angle of pressure relief pipework replace leaking magnetic filter with new Magna Clean Pro 1 filter add inhibitor to the central heating system If you need your boiler repaired or boiler leak fixed in SE19, Crystal Palace area or surrounding areas please book your boiler repair here Artykuł Emergency boiler repair in Crystal Palace, SE19 pochodzi z serwisu Urban Plumbers Ltd..
If your boiler is showing ‘Con’ message on main display it means that your main PCB or possibly display PCB has failed and will need to be replaced. ‘Con’ message means that there is a communication error between main board and display board. Both boards are connected directly with pin connectors so that takes out […] Artykuł Vaillant Eco Tec ‘Con’ error code pochodzi z serwisu Urban Plumbers Ltd..
If your boiler is showing ‘Con’ message on main display it means that your main PCB or possibly display PCB has failed and will need to be replaced. ‘Con’ message means that there is a communication error between main board and display board. Both boards are connected directly with pin connectors so that takes out a possibilty that a ribbon cable could have failed. Vaillant PCBs from R1 and R2 Eco Tec series are known to be unrelaible and ‘Con’ message is just one of the ways that PCB boards fail on those boilers. It does happen that those boards simply fail when the boiler is turned on and off at the spur switch and unfortunately it has happened to me on more than one occasion. Video below show a a Vaillant Eco Tec boiler with ‘Con’ fault problem. If your boiler is showing ‘Con’ fault code on the main display and you are in my area (Check areas covered on this web site) – please get in touch to have it repaired. The same boiler after repair below: If you need a boiler repaired and you are in SE or SW London you can contact me here plumber Crystal Palace Artykuł Vaillant Eco Tec ‘Con’ error code pochodzi z serwisu Urban Plumbers Ltd..
E133 error code on a Baxi/ Potterton / Main boiler is an ignition lockout fault code. This error code that covers a wide range of possible faults connected to gas and igniton. In most cases you will need to contact a competent boiler repair engineer but there are some steps you can take yourself before […] Artykuł Baxi error code E133 – ignition lockout pochodzi z serwisu Urban Plumbers Ltd..
E133 error code on a Baxi/ Potterton / Main boiler is an ignition lockout fault code. This error code that covers a wide range of possible faults connected to gas and igniton. In most cases you will need to contact a competent boiler repair engineer but there are some steps you can take yourself before booking a repair: check if gas supply is turned on – if you have a gas hob see if there is gas coming to the gas hob. You can also check if your gas meter ECV (Emerngecy Control Valve) is turned on parrarel to the pipework check if your meter has credit (Pre paid meters only) if outside temperatures are below zero – check if condensate pipework is frozen. If it is pour hot water over the pipework. check if your condensate pipework is not blocked If above steps did not help you will need to book a professional reapir. E133 error codes can be split into 2 groups (provdied that the error is not caused by lack of gas or frozen or blocked condensate pipework). First group is when boiler does not ignite at all. (Flame led does not illuminate and there is no flame visible in the sight glass) Possible causes in this case are: faulty gas valve faulty wiring between gas valve and PCB faulty PCB faulty ignition module faulty igntion electrodes gas valve out of calibration – wrong mixture of air/gas Second group of E133 error codes happens when boiler does ignite (flame led illumiates for a short period and flame is visible in the sight glass) – but goes out shortly after. In this case list of possible faults is shorter as we know that the gas valve opens and that igntion module is working fine. List of possible faults is as follows: gas valve out of calibration – wrong mixture sensing electrode faulty out of alignment sensing electrode wiring PCB Below you can see a video of a E133 Baxi Duo Tec boiler under fault condition. In this case the boiler would not fire up at all. The pump and fan would come on at full speed and there would be audible click / clang noise.The noise would happen exactly 3 times and then boiler would go to E133 error code. You can clearly hear the ‘clang’ noise in the video below. The noise was coming from the gas valve. After testing spark generator and confirming it was working fine I tested gas valve coil resistance. The resistance was in norm. However I suspected it was the gas valve not opening as it was making a rather unhealthy nosies. I also did not have apressure drop on gas valve test point – meaning that the gas valve was not opening at all. Have a listen to the gas valve ‘clang’ noise when it tries to open but fails. In this particular case the gas valve was faulty although the coil resistance was in norm. They require to be set up with a gas analasyer as they come unadjusted from the factory. After repair and careful setting up boiler is working happily again. (See video below) If your boiler suffers from E133 fault and you are based in in my area (see my web site ‘Areas Covered’ for details) please get in touch here gas engineer in Crystal Palace Artykuł Baxi error code E133 – ignition lockout pochodzi z serwisu Urban Plumbers Ltd..