Roomstat wont work after board change

[caterhamboy]

Hi, i swapped a cu yesterday and now the combi boiler wont operate off the wireless room stat. it works on advance on the boiler on still gives hot water. I did I/R reading between L-e N-E so can't be that, and rcd auto test in the board. The only thing i did was ZS from fused spur. I have tried paring the roomstat again and changing the battery's but it still wont work.

 

[SirKit Breaker]

Cant see how a CU change would stop the stat from working, and neither would a Zs test. It sounds as if you have just been unlucky and the stat chose to die at the same time as you changed the CU. Fit a new one and see what happens.

Cheers.......Howard

 

[caterhamboy]

Could it have been the rcd auto test thats damaged the pcb?

 

[tonys]

Do it work before you touched anything ?

I don't take chances with IR Tests unless I disconnect items like combi's which house electronic components. I would phone boiler technical for advice.

 

[caterhamboy]

Yes it worked fine, Didn't disconnect it tho, but was careful only doing I/R test L-E, N-E. The only thing that could have caused any damage? was rcd auto test from out going on mcb and earth bar. Never had a problem before tho.

 

[tonys]

Know it a bit late mate, but I do RCD testing at terminals with loads disconnected.

 

[Spudnik]

Believe it or not, i did a CU swap yesterday and the client phoned yesterday eve saying the CH progammer had no lights on it.

Got down there and yep, no lights.

Turned out to be U/S ( it was over 20 yrs old), so replaced and now all working fine.

i have no idea why it went and usual precautions were taken when testing...

 

[fire]

next time do an IR test at 250 and not 500 that might help. or connect L and N together in a connector block and do IR test between that terminal and earth at 500. this wont damage electronics.