CM927 not turning boiler on or off

23 Oct 2009
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United Kingdom
Hi, i have a Sime format 100c boiler. i have connected the HC60NG terminals as follows:

N and L to the mains supply
A to 10 on the TA
B to 11 on the TA

Set the timer in the SIME Boiler to the I position (continuous)

I have configured the CM927 with the HC60NG. s now if i turn on the desired temperature on the cm927, the led on the hc60 lights up, and wheni decrease it below the current room temp the led goes off.
So the CM927 and the HC60 are talking to each other.

But when the hc60 lights up, it does not turn the boiler on :(

Previosly it was connected to a manual T6360B controller and if i put the A&B cables back in there and turn the dial, the boiler does respond very well..

What couold be wrong? could it be a faulty HC60?
can anybody help
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But when the hc60 lights up, it does not turn the boiler on. What could be wrong? could it be a faulty HC60?

Do you have a multimeter?

If so, temporarily disconnect the wires from the HC60 terminals A and B and check the continuity between A and B when the stat is turned up to max. If no continuity, the receiver is faulty.

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