Dear Muwafak, thanks for the kind words, glad to help, take care, George Staszak 🤩👍

Thanks for comment, yes you are correct, too many installers still don''t do a short circuit test and spend hours on a fault then give up.All the best, george 🤩

👍thank for comment, take care, george

Dear Doves, thanks for the kind comment glad you found it helpful regards George Staszak

Hi Mo, Thanks for the kind review, it's good to know my videos are making a difference, take care, George Staszak

@@mrcombiBedford Thank you very much for your reply. I strongly believe that people who spread and share their knowledge to others, only for sake of god, they always get rewarded🤲

@@MOB30A Thanks you are correct, regards george

Hi Munn91, Thanks for asking, All combies and HW cylinder settings the HW MAX is 60C, (except combies in the late spring / early autumn maybe turn down to 40C because the incoming water is hotter) CH all combies are set to 75/80 which most homes is TOO high (expensive) If you can set 60C saves lots of money! Danger, see my videos on heat loss etc. too many installers don't do this, stick any undersized rad in the lounge, to get hot the home owner has to turn both stats high to get warm and expensive. All the best, George Staszak

Thanks you for your comment, all the best george

Hi Ivan, thank you for the nice review, take care, george

Hi Roy, Thanks for asking, very easy to test Vaillant or any boiler for NO CH. I assume the new stat is digital, turn it down to the lowest setting. If you DON'T have 230v on 4 SW.L its controls If you DO have 230v on 4 it's the boiler / pcb. 1st Turn OFF the power to remove (in your case) the wires from terminals. 3 Com. and 4 SW.L and make safe the ends. Link a wire across 3 & 4 now you are to factory mode. Power ON select max CH on the boiler front, if it works you have a controls fault, ie. programmer R/S or the wire in-between. 2. VOLTS: Check 230v from EARTH to L. 0v on Natural 230v 3 and and on 4. < 230 on 3 that's PCB, if more the 6 years change for latest version, if boiler is about 12 years change it etc.etc. because not economical to repair. Hope that helps. All the best, george 👍

Thanks for your kind comment, all the best, George Staszak, ❤👍

Hi Brendan, you are correct, this easy test will show if safe to switch on without blowing up. take care and thanks for you comment . george

Their. You're welcome.

Hi Mo, thanks for asking, as with all boilers the NTC / sensor testing is the same, at room temperature 20c (the boiler is cold) check the ohms of each sensor to specks, normally 10 - 12KΩ : Vaillant are different only one wire to earth ( I love this method, dry pocket one wire to earth) the value is 1-5KΩ at room temp about 2.5K. The green sensors eg. Ferroli you must call tech for values. There is a chart which is in the Wednesday course notes but ask your boiler tech. for a download. regards, George Staszak.

@@mrcombiBedford George you are a angel. Thank you very much and God bless you.

Thanks for the kind words, take care, george staszak

Hi Korhan, thanks for asking, love your boiler installed and fixed lots, there is always a risk when the power is turned OFF for the PCBs and programmers to fail, I always told the customer, this affects anything past 8 years, the software cannot cope with the switching ON surge. I had a look at cost of both boards £300+ fitting? To be honest start again, as I have said many times rip the whole system out, or really flush 3 times, recalculate ALL the rads, fit balancing TRVs, auto by pass enjoy the efficacy and save MONEY compared to this boiler. To get the longest guarantee find a factory hero installer have it seen EVERY year to keep the insured policy. get 3 quotes, hope that helps, regards George Staszak 😄

Thanks for asking Both the Faults and Wiring books have all the 4 part electrical safety testing info that you need, use this link to order www.mrcombi.com/shop/ The Faults book is better because it's all about testing and fixing boilers. regards, George Staszak

Hi San, thanks for asking, NO the pcb HAS to have a 2 amp which is weaker than the 3 amp in the wall to stop it blowing up. Power OFF measure in ohms L & N on the pcb, if less than 100 call the factory engineer or local hero to find what is causing a short circuit. If the pcb is over 5 years replace but you MUST find out what the actual fault is otherwise the new pcb will blow up !!. regards George staszak

Forgot, next week a new boiler it's not worth fixing

Hi Chohan, I hope not, the main reason they blow up is age (over 8 years old) and another part (pumps) cause damage. regards, george

Hi Stephen, thanks for asking, have a look at my PCB video, you need to have +230vAC at the switch in the OFF mode, if it's ON then the boiler would start up and blow a fuse also we don't want the boiler working whilst testing that would be very dangerous. Hope this helps, George Staszak

@@mrcombiBedford Hi George. The Baxi 600 & 800 combi range don't have a on/off switch on the boiler. On & off comes direct from the fused spur.

@@SD-Plumbing-Heating How strange, then you shut down via the programmer both channels to OFF to stop it working, regards, George Staszak. Happy New Year to all and thanks for the comments

Thanks for asking, easy one or more of the soldered joints has dried out, know as "dry joint" not possible to test every one thus replace with the latest version, don't buy a recon. take care, George 🤩

Hi Mark, thanks for your comment, take care, george

Same! Was informative either way

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 🤩👍

@@mrcombiBedford thankyou

Hi Nath, thanks for your comment and of course you are 100% correct, what that would show is the low impedance metre is the wrong one and the person has not been trained which metre to use and should not be doing this test. Many come here with wrong metres even G clamps to fix boilers? regards george 👍

Dear Hu, any volts on Natural is a house wiring fault and will cause a fault on any boiler, thanks for the comment.

@@mrcombiBedford Thanks for reply. I am NAPIT full scoped. Only TN-C-S earth arrangement, Neutral and Earth Voltage should be zero. others like Ture TN-S or TT earth arrangement, Neutral and Earth Voltage always not be Zero. People always say Neutral and Earth Voltage be zero, because today most of property earth arrangement are TN-C-S system or not true TN-S system. For TN-S and TT system, Earth is always the true Mass Earth. So there is current flow back to transformer by Neutral conductor ( Three phase not always/unlikely balance, neutral current is always present), so there is voltage drop between neutral inside property and connected point which neutral and earth combined together at the transformer winding and case. For TN-C-S, the Neutral and earth combined at the cut out inside the meter box, so TN-C-S neutral and earth should be zero. Regards

@@huyongquan6554 Many thanks for the update, take care, george