Gav_P

Wow, that’s intersting news. I was a bit concerned going down the ASHP route, but it keeps offering up more benefits over traditional oil boilers. did you need the carrier command unit to change any setting to make it work? (I don’t have one of these currently)

This is interesting... is this for Air to Air heat pumps or does it work for Air to Water? Does this mean I could potentially cool my UFH in summer?

I bought my ASHP for £250, it was new but obsolete.... it took me 3 years to fit it... so when it came around to the time to switch it on I was very nervous that it may not work. It turned out fine and worked without any issue (until I did something stupid to break it anyway). I would follow the advice of waiting until you are ready for it for several reasons over and above the obvious of returns / warrantees etc. - there are always bargains to be had on eBay, so no rush now. - It’s more likely to get damaged or nicked. - but the longer you wait the more the prices come down on better spec equipment, so the longer you wait the better the ASHP you are likely to get for the same money. The other thing to remember is all the installation equipment needed. Flexi pipes, control unit, wall brackets or pad and feet, etc

I think this would be a suitable replacement: https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F283148597323 but it seems to be an older version, not sure if that’s an issue?

? done!

Hmmm not sure how i’ll get on poking around in such a small space with my clumsy hands and cheap tester.... but as Del says “He, who dares, wins Rodney!”

@Ed Davies Nice guess... it’s 7812B

That would be nice... if they were cheap

The whole thing is weird to me. Never could get my head around PCBs and small electronics. Ive just double checked to make sure I didn’t make a mistake, but it’s definitely the air sensor.

@Ed Davies yes they go to 23 & 24 which is.... *rummages through the book* an optional external airsensor apparently.

@Triassic sorry no, I wasn’t very clear. This board has an LED that flashes at 1/2hz when the unit is on, but it flashes different sequences if there’s an issue. However this board is inside the unit and you have to remove panels to see it. So there is an external ‘alarm unit’ that you can wire into it that can be sited somewhere more convienent (like indoors). So I connected the 3 wires to the appropriate connecting block (off to the right side of the PCB pictured here) and then poked the wires through the house wall. But because I stupidly assumed it was 0v I left it live whilst doing it.

@Ed Davies cheers. I wasn’t sure if I started removing it if it would do more damage or what to replace it with.

@ProDave Magic thanks... I’ll take a go at that.

@ProDave thanks. I’ve check the fuse, that’s the 240v that go to the transformer on the back of the board returning (as you point out) via the 2 red wires as 12v.... after that I haven’t got a clue. And not sure how to test any of the components. Plus they are all coated with something (I assume to protect it from the elements) so I can’t get my tester on anything.

@ProDave how’s that?

@JSHarris thanks for the quick response... I’ve popped the GMC out and can’t see a 12v fuse anywhere, so I think I’m going to have to suck it up and spend some money on it. I just begrudge spending £100 on a board when the whole unit was only £250 (new old stock).

Hi all, I’ve been a long time lurker, but this is my first post on the forum... of course it’s because I have an technical problem that I need help with, and based on all the previous discussions on here I’m thinking there is more than enough experience to enlighten me! I have a 4kw Kingspan Aeromax Plus KHP0041 (made by Carrier), heating my UFH system downstairs and radiators upstairs, all was working fine until...it wasn’t. I have 240v in the unit, but no blinking LED on the GMC board. Now i’m not certain what the issue/cause is, but it might be related to the fact that I decided to wire in the alarm unit, so I could see from indoors if there were any issues without having to go out and open up the unit to look at the blinking LED on the GMC board. For some reason I thought it was a 0v feed so didn’t switch off the power and when posting the wire thought the wall I think I shorted it out... as I’m fairly sure it’s actually 12v. So without giving me too much grief for being stoopid, do you have any other suggestion of what would cause the GMC board LED to stop flashing or how I could test it? Before I go and buy a replacement PCB. In penance, I do have PDF copies of the Kingspan Installation Manual, the Carrier Service Manual and the Carrier Spare Parts document. If it’s of any use to anyone. Thanks Gav