Thermostat Not calling for heat?

hi all.

wondered if someone could possibly shed some light on my situation. I bought a digistat +3 to replace my analog stat. I stupidly connected the wrong wires, including the neutral, which i now know to be wrong. needless to sat i blew a fuse. So i replaced the fuse and put back the old stat. after browsing the net found out what i should of connected etc and did as it said )on the new stat). As i turned up the stat the relay clicked as it should but the boiler didn't spark up, a little confused put the old stat back on and the relay clicks too but still doesn't actually call the boiler. Have i damaged something on either the boiler or boiler mate II?

Appreciate any replies

John

just to add its a potterton suprima 40 boiler which has had the PCB replaced

The use of a multimeter will show you whether the thermostats are actually calling for heat.

It is unusual for the old thermostat to have a relay in it - I take it was a Drayton Digistat?

It is possible the current surge when you shorted the Digi3 damaged the programmer. Or if you have one of those horrible Honeywell wiring centres with the white wire links there is an internal fuse.

But the only real way of diagnosing your problem is with a multimeter, you can buy a horrible one for a big benner.

i have a multi meter. What would i be checking for? on the boiler or the boiler mate II? I just figured they have relays as you hear the click as it engages, sorry for my mis understanding. I understand that diagnosis is hard over the net but if you could guide me to make the diagnosis then it would be much appreciated.

John