Hi, I've been a bit of a lurker on this fantastic site, happily soaking up information and tips. I'm not a self-builder (yet - it is certainly a dream to one day take the plunge), but a DIY maintainer and updater of a couple of houses.
We recently bought a house here in Luxembourg (built in 2009 out of plenty of concrete and the most solid blocks I have ever come across). The main heating is UFH, heated by a district hot water station, the controls for which will be the subject of a separate post...
The house also has three wall-mounted Haier air conditioning units, each with its own external unit. One has never worked, not showing the slightest interest in life. The other two work (although one of them only after swapping the capacitor from the dead'un) - until now, when a second has died whilst in heater mode: the louvres remain open, so not a controlled shutdown. I have checked the obvious: electrical supply, connections as well the fuse located on the control circuit board which seems purposefully designed to be dropped into the guts of the machine. When we bought the house, the sellers said they had never used the AC units, so that is at least 5 years of disuse.
So, a couple of questions.
The first is sort of in the title: is an AC unit an ASHP which I should be able to use for supplementary heating, or is it likely the heating was supplied by some sort of element which burned out causing the unit to fail?
Is there anything else I should check - any fuses I haven't found in the external unit?
I plan to replace all the motor capacitors, is there anything specific I should look for? I think it should simply be a straight swap of a new 450VAC 25μF polypropylene capacitor, but is there any other specs I should be looking for?
Any thoughts would be very much appreciated.