We are a small family business in the world of domestic central heating.
Since 1970 when George Staszak was one of the first who became a CORGI reg. gas installer in Bedford and retired 45 years later. In March 2002 Mr Combi Training was opened over 5000 attended George's master class in over 20 years, George retired in September 2022. A regular guest on local BBC radio and contributed on BBC 'Watchdog' program helping to solve problems, noisy boilers, cold rads, save money also where installers and electricians got some instant advice.
Our You Tube " How to" videos are are posted regularly designed to help solve issues hints and tips to lower the fuel bills for endusers and installers
We have available 2 books and Apps on our web site www.mrcombi.com or app store to help and make a difference.
sir I have a question, this aqua signal ignites the gas boiler but is it a continous signal or just a one time ? the reason i am asking this is , i am doing a project and i have connected a electric heater to heat water but i dont want to run both heaters at same time and want to save my gas money so i figured if i just block this aqua signal , i can stop gas boiler from igniting ! so please if you reply it will be a huge help ! thanks in advance!!
Hi, thanks for asking, All combies have 2 switches 1 for HW and 1 CH which are NO (normal open) dead, until a tap is turned ON. There are only 2 ways to start ignition 1 sensor (Ohms) the PCB see's a change and starts up, or 2 a switch is activated from NO the NC (normally closed) and the boiler starts up until the tap is turned OFF then back to NO shuts down. I don't understand why you want to connect an ELX heater as it's 3 times more expensive than Gas? You can just unplug the aqua sensor from the PCB and enjoy big bills. If you want at add HW cylinder see my video on add 2 zones to a combi or any boiler. hope the helps, George 🤩👍
Hi again, Smart TRVs are very expensive Amazon £274.00 for 5 heads is completely unnecessary because the payback cost will never happen, EVERY rad needs one, just like Air source / Solar and EVs 👍 Smart controls 100% save money balancing TRVs, Heat loss of the home / lounge 60c flow is the way to save money. Why some people spend 1000's to save what? When I added what I paid into my pension I have to be 117 before I make £1.00 profit. I paid for their big building and bonus. Hope the helps, George 😀👍😤
@@mrcombiBedford okay. lastly one more question. if you have smart thermostat in hallway and radiator, you said it should be fitted with a trv. i was under the impression area with thermostat shouldnt be fitted with trv. otherwise both will compete, and also there is no 'bypass' for the boiler incase other smart trv's are off when the heating might be commanded
@@mohitl1697 Hi Again, no problem, as always every rad needs a TRV if the stat is in the hall a TRV must still be there, in a ROOM not allowed both. Ignore what is in the boiler has fitted, as I say many times the rules and Codes of Practice and CONTROLS firms demand an external auto by pass on EVERY system. It's the CONTROLS firms demand an external by pass NOT the boiler manufacturer. Installers wrongly keep thinking it's a boiler requirement when it's not. take care, George 🤩👍
Hi, thanks for asking, the X100 or Fernox F1 are very good inhibitors I highly recommend refilling with them if the system has been correctly. If not X200 or F2 are a more for problem solving, eg. noise or blockages pump problems which is often the case. Hope that helps, George 🤩
Hi 33, thanks for asking, over because we have to have a HIGH resistance to stop fuses blowing, 100 Ohms is the standard value that we work to. It should be O.L. (over 1 million) but some firms don't use the PCB the same way. Hope that helps, George 🤩👍
Hi Nick, thanks for comment, because of a shortage of engineers who get richer and richer this will only get worse for customers. No one wants to do this job, shame. all the best, George 😍
Hi Dickie, thanks for asking, Hz is not just used as a radio or TV frequency but it's the best way to measure a pump / fan or anything that moves. I found Vaillant publish lots of data in Hz. A pump can be 2K revs but we can't measure revs. but we can in Hz. which is 100% accurate. Most will use Ohms and volts which is OK but Hz is faster and more accurate . Hope the helps, take care George 🤩👍
Hi Michael, just going to have lunch, a mid Poz. valve has a gap of about 18mm to the heating side, that only allows 13kw of rads, its recommended only 10kw because the big double K rads at the front of the house will not reach max temp 75C the result will be the boiler stays on much longer and high fuel bills. Remember it's the boiler RETURN stat that switches OFF the boiler. It's better to over size the rads with a LOWER return temp. use my "Heat loss App" and you will amazed at how many rooms have under sized rads 22mm Zone valve can have about 20kw of rads recommended max 18 better to split the system to 2 or more zones to lessen the boiler stress and much cheaper to run. Thanks for asking, Marmite crumpets are go! 🤩👍
Mr Combi, great channel with sound information thanks. Can you help me with a solar thermal tank project. I have a Valiant Ecotec which is a cracking boiler, I am fitting a thermal solar tank. Now some boilers can take the preheated water in and top the temp up and others can't. A blend valve to limit the input temperature is suggested on some installations. Now can I feed my boiler from the tank or can I tie into the hot water pipes via a diverter that favours the solar if hot enough. Thanks for any info and thanks for you straightforward presentation.. Best.
Dear Woffy, Thanks for the kind words, not an expert in that field I would go to Vaillant for advice. Don't like air source or EV's I would never take any advice about heating or cars from a politician. All the best, George 🤩👍
Hi I have just bought the fault finding app from Apple app store and none of the videos play. How can I get a refund please. I have try emailing you from the app and the email was returned saying couldn’t find address
Is the fault finding book the same as the fault finding app because I use a tablet when I’m out on the job. Plus a few people have commented on the videos not working on the app has this now been fixed. Great content by the way
Thanks for the question, the book has a lot more information we always advice have both books and all the APPs. if you are an installer or breakdown engineer. The APP has 21 "How to" chapters the book has flow charts, No ignition and so on. The 2 video APPs are being updated hope to be finished in a couple of weeks, (the icons are amazing) Don't download until done, the other 6 will be next. All the best George Staszak 🤩👍
Dear Gixxer, thanks for asking, I cannot show you how to wire a digital stat because each firm has different terminals, you would not change to the same type, 2L +N, all digital. have COM and SW.Live same goes for Open Therm. some will be 230vAC or 24vDC or Volt Free it depends on the one you buy, as in other Vids. if your boiler has O.T. that's the lowest running cost after that VF then 24vDC avoid 230vAC. hope that explains. Our Wiring book and APP has more info. take care, George Staszak 👍
Hi George. Just sidetracking slightly but I have a customer who upgraded their Landis & Gyr roomstat to an RF EPH stat but didn't want the old stat removed. The installer set the old stat to max and told them not to use it but use new RF stat. This is correct as far as I'm aware but I think they have been moving stat probably due to habit. So, going to link wires behind stat just wanted to confirm which ones to link out. Thanks
Dear Gas NW, Thanks for asking, yes you are correct the old stat MUST be disconnected, I understand they don't want to remove the old one before decorating. Power OFF and remove the wires from the boiler end and make safe (don't cut them OFF, someone may want to reconnect them later). Hope that helps, George Staszak 🤩👍
@@mrcombiBedford Hi George. Many thanks for the information. Its an old heat only boiler so will I need to put a link back in on the boiler end so that the EPH twin channel programmer controls the switch live to the boiler? Thanks
I feel my radiator nearest the boiler get slightly warm when running a hot bath. Is this normal for a combi? I think it's done it since I moved in 12 years ago
that's vaillant off my list then. my ideal has a preheat button which you press once and it puts preheat mode on - none of this press triangle square and x, hold left joystick down, count to ten, turn round and touch your toes nonsense.
Tinnitus, have had this for fifty years and it is my annoying friend !. Very important you don't focus on it, accept that it is there and get on with life. Mr Combi has given some good suggestions and I use these techniques to keep the tubes clear. The Eustachian tube is normally closed but opens when we swallow, yawn or chew. This allows air to get into the middle ear and any mucus to get out. This keeps the air pressure equal on either side of the eardrum. Having equal air pressure on each side of the eardrum - and the middle ear free of mucus - helps the eardrum to vibrate. This vibration is needed for us to hear properly. My analysis of some forms of. Tinnitus can be the reproduction of a tone which you have had long exposure to including something like a computer fan, for example you hear a constant tone in a space from something, the brain counters that like noise cancelling earphones and turns down the gain for that frequency. When you leave the space the brain no longer hears the tone and but is still cancelling the tone but as it is not there you hear what the brain is producing. Don't Focus on it and do speak with your Doctor about your hearing. Good luck I am taking my friend for a walk..... Good advice Mr Combi
Hi Jez thanks for asking, its the gas valve, after a few years it get out of settings and often does not close promptly thus sues more gas. sometimes it just shuts down, dead. Often it's replaced with a different model same as PCBs, that's why I say after 4 years check the firm for updates. take care, George Staszak 🤩
@@mrcombiBedfordHi George, I’ve literally been noticing this issue with Ideal Combi2 boilers. Mainly with the C24 model which when running gas rate checks seem to be sometimes about 3KW - 4KW overgassed. Maybe they have a gas valve issue with this model as these are relatively new. Also would a faulty PCB cause a higher gas rate?Thanks, Dan.
@@DanielGreen_690 Morning Daniel, not the PCB, 1st. call the firm to report the issue feed back is vital to them and ask for guidance. I think just reset the GV come back after two weeks and retest / replace or it's OK. Many thanks for asking and have others had this common problem? Please leave a comment below, take care, George Staszak 🥰👍
This video is a life saver! I’m usually pretty good at figuring out stuff but I could not figure out how to set my heating timer to once a day! Thank you so much! ☺️
10.20am, good video, very informative. Question How do you work out the size of an expansion vessel. For instance a system with 17 radiators, mostly large, 3 zones, to 50 kw, commercial boiler, no expansion vessel present. Ray Majrowski. REM plumbing and heating. Thanks.
Hi Raymond, thanks for asking, The best place for advice is the boiler firm, officially we add all the water content of the rads, pipe and boiler, good luck. As its commercial which is not my world, I would expect between 20/30 ltr. would do, better over size than under. take care, George Staszak 🤩👍
Thanks for this helpful video but in the places (8 mins 35 seconds onwards) where you talk about the blue wire, we can't see the wiring mistake you are referring to in the video and the discussion about the blue wire is not clear. Could you please show the wiring of the old thermostat that has been done incorrectly and the new correct way for a digital thermostat. I have just installed a digital one(Siemens RDH100) and I used only the yellow and red cable because those were used in the old Honeywell I was replacing. The blue wire was already cut off but not sleeved or taped up. I replaced the Honeywell because I was suspicious that it was not turning the heating off in time. So potentially overshooting and strangely it was also not turning on the heating early enough either.
Dear AR, thanks for asking, I have lots of drawings in other vids APPs and book, that shows what you are asking. The old 230vAC room stat has to have 3 wires, the neutral we don't need in digital stats so we make it safe and use the other two as they are Com and SW.L. Hope that helps, George 👍
@@mrcombiBedford Thank you very much George. I managed to get the thermostat installed using the 2 wires. I am experiencing that under the stairs location problem though. Even in June, the temperature under the stairs is dropping to 18 degrees, causing the heating to turn on. I think I need to configure it for a 2 degree differential so that it only switches the heating on when there is a 2 degrees difference. Thanks again.
Thanks for asking the blue wire is with the black wire that’s wrong All the blue wires should be together and never with others Hope that explains George
Hi George, If you don’t mind me asking, how come you don’t the in-person courses anymore? Could you recommend where I could go? I’ve just finished my MLP and while your books and apps are very helpful, I need some hands on experience. Many thanks
Dear Met, Thanks for your email, I have retired from training after 20 years to concentrate on RU-vid videos, www.youtube.com/@mrcombiBedford/videos where I can reach more installers. Please subscribe to us and watch the Vids. They are made for you. We also have a load of APPs plus 2 book, for you or anyone in the heating industry. If you need “hands on” training then go to the firms, compulsory Baxi, Worcester Bosch, Vaillant plus my favourite is Intergas. For controls Drayton + (RU-vid vids) + Honeywell Home. Takes Care George Staszak😍👍 Mr Combi Our APPs are all one price £4.99 no vat www.mrcombi.com/apps/ Apple iOS download: apps.apple.com/gb/developer/m... Google Play download: play.google.com/store/search?... BOOKS: www.mrcombi.com/shop/
@@mrcombiBedford Hi George. Many thanks for getting back to me. I’ve got the apps and have just ordered the books. I will hopefully be attending the manufacturers courses as you have advised once my ACS comes through. Drayton and Honeywell only do online from what I’ve seen. Many thanks
@@IncredibleMet Unfortunately that's the norm, it is very expensive to invite 12+ engineers and feed them etc. and a lots just don't turn up because the cost is too low. One firm told me of the 12 booked 3 came, a lot of food was wasted plus 2 Reps hotel bills. This is why they stopped. Take care, George
@@mrcombiBedford Hi George, I’m having issues with the apps. I’ve emailed the app support email. Would appreciate it if that can get sorted quickly so I can start learning! Many thanks
@@IncredibleMet Dear Met, We are still trying to find which code has been deleted, We have a plan B and I will get in get in touch. Thanks for waiting Sales 👍
Hi, my hot water pump is constantly on even though the hot water and CH is off. I changed the motorised valve but the issue remains. Any idea? Thank you
Dear kr173sh, Thanks for asking, who told you to change the diverter and how did you test it? If the pump runs in HW the stat is still calling, see my videos on HW and Diverter faults and how to test parts. 🤩👍
how about, pump makes litteraly 0 noise? and still not working, not even the pipe hot water aint working which i supose does not relly on pump... wtf is wrong with that stupid thing... It starts burning, it starts heating water, then you can hear the switch and immediately shuts it down, and the 'sand clock' diode keeps blinking
Hi Nikola, Pumps and heating systems must NOT be tested in HW mode only in Heating, because it tests the diverter valve has moved and many boilers do not use the pump in HW. If the heating is OK then the FLOW pipe gets hotter, if not either call a breakdown engineer or factory Tech. Dept. All the best, George Staszak 👍
Hello! Can anyone help me with my issue? Namely, from some reason, heating is not working, and I tried to check the pump, by unscrewing the cap as in this video (to try to start it manually by screwing the inside screw), but when I removed the cap on the pump, water started to come out in the stream. I closed it quickly, as pressure started to go down. Is it normal thing? Do I need to ignore the water stream and to try quickly to unscrew the screw inside the pump to check if it is jammed?
Hi Milan, thanks for asking, as the video shows that screw is only for venting, not for spinning the propeller. There are many reasons why the heating is OFF, programer / room stat fault, stuck in HW mode, pump Ohms test, best call a factory training engineer, regards George 🤩👍
The pressure in the system was too low, and I did notice that. And once, it stopped to work. I added water in the system and increased the pressure, but it still does not heat...
I also checked the pump now. I hear that it works (at least I think that was the sound). When I increased the speed of the pump (on the button), I could hear that the speed was changed. I think that pump is ok. Room thermostat is also ok, I checked. What could be next on the checklist? Sorry, I did not understand the abreviations you listed in your message...
Hello there, I have the same set up that you show with the Honeywell thermostat with the wheel and the ST9100C. I want to replace with a smart system, if I choose the Honeywell T6 Wired smart, I need to put the thermostat with the display instead of the one with the wheel and the receiver box instead of the ST9100C module correct? Thank you for your answer.
Hi Stefano, thanks for asking, No the wheel is too old, replace with Drayton RF 902 2 channel about £117 from Toolstation, this will save you money and easy to use Take care, George Staszak, next week I will have a video on changing rubbish Combi controls system to to RF901 single channel, just what you need except one channel. 🤩👍
Dear Fibre, this is true but Tech. Dept. will always quote (and we test) pins 1 to 5 to see if open circuit then no need to test each one. take care George Staszak 🤩👍
Do the same rules apply if you have a diesal oil system boiler with a 14 litre internal expansion vessel using in conjunction with a 300ltr unvented cylinder for both CH & DHW?
Hi Patrick, Thanks for asking, the boiler and cylinder has nothing to do with the EV. It's the total of water in the rads plus pipes. E.G. If the system (rads + pipes) has 50 ltrs. at 1 bar pressure, we know water above 50C WILL expand by around 4% = 52 ltrs. and the pressure WILL go up 1.5 or more, danger! The installer HAS to fit an external 12-16 ltrs vessel to stop the rise, often NOT done and fit a external AUTO by pass also often not done. The result: The pump will make sludge, noisy boiler, often breakdown, short life. It's basic installation requirements as I said too many installers will ignore Codes of Practice because breakdowns make money. Hope that helps, George Staszak. 🤩👍
