figure this one out then...

[sparky3366]

After fitting them and finding the easy to do, I go to fit a wireles timer/stat to mother in laws combi...a baxi 105e. Open the cover to find the neutral & live reversed on the main incomer for the boiler...fit the wireless receiver and put the wiring in the correct way, nothing. reverse the l&n again...it works. WTF???
Checked the fcu...all correct. Beats me...

 

[telectrix]

welcome to the twilight zone

 

[Guest123]

From memory, those Baxi's have fuses on both L & N on the incomming supply at the boiler.

Could it be that one fuse had blown and they'd swapped the connections over as a spare fuse was not available????

 

[Marvo]

Hmmmm. A couple of thinks spring to mind you might want to check before you call in a Priest. As Lenny suggests maybe the live fuse blew and there's a massive insulation fault. Reversing the L+N then allowed the boiler to operate to the earth fault instead of the neutral.

Secondly, and this is a long shot, some wireless devices use an earth referenced digital communications system between the wireless gizmo's. This would make the device sensitive to power L+N reversal. It would also mean the supply polarity would have to be mislabeled as well. Like I said....a long shot, maybe the Priest and a full exorcism is a better idea