Air Pressure switches

[Tone1201]

Just bought a honeywell C6065AH1020 pressure switch having been told it is a uniform replacement for the one in my Sime Friendly Format LPG boiler, BUT
the contacts on the honeywell are C, NC and NO
the contacts on the Sime are 1 2 3 with black red and brown wires respectively attached. no instructions have been supplied with the honeywell. Please can anyone offer assistance as to what colour goes where.?
Many thanks

 

[nwlondon]

have you a circuit diagram of the wiring system in the lid of the boiler? I had the same problem but with a potterton profile 50e and the annswer was their.

 

[Tone1201]

i have circuit diagram for the whole boiler but it just mentions the wiring colours for the original installation. Can you help with what C, NC and NO are in relation to red black or brown?
Many thanks

 

[superdupergasman]

C = Common
NC = Normally Closed
NO = Normally open

From the circuit diagram you should be able to decifer which is the input side to the APS hence 'common'

this line will then goto the NC connection and the last one is the NO

 

[Tone1201]

sorry to sound a bit nieve but would common then mean the red wire?

and normally closed will mean the black wire.

Many thanks so far your a great help.

 

[EliteHeat]

Common will have a voltage on it, the others won't when not connected to the APS.

If your original APS is really duff, then it should be obvious where the other two wires go.