Combi boiler

[ed-ectrician]

I am a spark, done lots of everything domestic but never did boilers. 2330 is the PRINCIPLES of electrotechnology unfortunately they dont tell you how to do absolutely everything that's what experience and this forum is for! The bloke asking me to do the job is a heating engineer he hasnt got a either! Ta!

 

[mountainman]

Sorry if i insulted you but your comment about a wireless stat not having a cable tickled me, does it not have a receiver that is wired?

And a heating engineer who doesnt know how to wire a combi or follow the MI's would worry me considerably.
I hope that he is GSR.

 

[Merl]

Swicade has it covered in a nutshell!

3 core flex to boiler from 3A SFCU. 5 core flex from boiler to wireless room stat receiver unit as per wiring diagram 'b' page 7 of the link you posted.

Hope it helps!

 

[Swicade]

I wire them exactly as Merl says....the 5 core flex from boiler to room stat receiver gives you live,neutral,earth supply to receiver AND live/switch return from control terminals on the boiler to contacts on the receiver.

 

[ed-ectrician]

Yep got it now!! Sorry it took me a while! Not insulted just explaining where i'm coming from. Final question, if i dont get this honeywell one are principles the same for most similar ones the only difference being more or less switched lives.

 

[Geordie Spark]

Yep got it now!! Sorry it took me a while! Not insulted just explaining where i'm coming from. Final question, if i dont get this honeywell one are principles the same for most similar ones the only difference being more or less switched lives.

All wired stats are pretty much the same as each other, the only difference being some need a neutral running to them so they are known as 3 wire stats (live, switched live, neutral and of course the CPC) while others only need live and switched live & CPC. These are known as 2 wire stats.

Wireless stats are all pretty much the same as each other too - as far as installing them is concerned anyway.

Whichever method you choose - wired or wireless - you have a choice between a simple thermostat or a programmable one. The simple one is used in conjunction with a time switch of some sort which can either be built into the boiler, or a stand alone fixed to the wall next to the boiler.

The programmable thermostat incorporates its own timer and these can switch the boiler on & off at different times of the day and can also select different temperatures for different times of the day, and a completely different set of switching times and temperatures for weekends.

 

[mountainman]

Yes they are all very similar, just read the 'stat wiring diagram in conjunction with the boiler wiring destuctions and all will be good.

 

[ed-ectrician]

Customer doesnt want to pay over hundred quid for the honeywell 927, no wireless needed. Any recommendations for a simpler cheaper stat? Thanks

 

[ruston]

Customer doesnt want to pay over hundred quid for the honeywell 927, no wireless needed. Any recommendations for a simpler cheaper stat? Thanks[/QUOTE

Be more than that if you have to hack a cable in to do it the hard wired way.

 

[Geordie Spark]

Dear God ....... I give up !!!! :hanged:

 

[ed-ectrician]

What about the CM901? Looks like it could work

 

[mountainman]

I really dont care anymore, sort it out yourself or get the 'heating enginee' to decide.

 

[ed-ectrician]

Ok it's gone on long enough!! Thanks for help everyone.