wiring for room stat

[ExArmy]

i'm doing a rewire at the mo, the customer has said the plumber has asked if i would run a cable for the room stat while i was at it. will 1.5mm t+e do the job?
should i just terminate in a joint box as it comes into the old airing cupboard (where the boiler will be) and then run some heat resistant flex from there?

 

[Guest111]

1.5 will be ok just make sure you run 3 core and earth as unless it,s a low voltage stat it will probably require a neutral as well as live and switched live.most do then to jb and hr flex to boiler sounds ok to me.

 

[TaffyDuck]

Triple would be better, then HR to the boiler will be fine.

 

[Sparkystu79]

Quite often a room stat requires a L, N and SL so it would be safer to run a 3c+e if you don't know which stat you are fitting.

 

[D80]

1.5MM T&E + PVC/PVC single is the cheaper way to do it usually, I find 3 core is a lot overpriced! This way saves the bother of having to sleeve the black & grey cable as they will already be coloured brown & blue throughout the length of the runs anyway.

 

[DurhamSparky]

tell customer to stop been cheap...!

get a decent controller with wireless stat made by honeywell...!!

 

[TaffyDuck]

wireless stats are for plumbers :6:

 

[ExArmy]

thanks for the replies guys, 3 core it is.

and durham, I did suggest a wireless stat but this is doing up houses on a budget, at first they wanted me to re-use all the old accessories that were about 30 years old! and i got a funny look on the first day as i loaded a bag of copper scrap into the van, i think they wanted me to re-use that too...

 

[Guitarist]

thanks for the replies guys, 3 core it is.

and durham, I did suggest a wireless stat but this is doing up houses on a budget, at first they wanted me to re-use all the old accessories that were about 30 years old! and i got a funny look on the first day as i loaded a bag of copper scrap into the van, i think they wanted me to re-use that too...

At least you are recycling.... :biggrin5:

 

[micknew]

wireless stats are for plumbers :6:

Or electricians when running a 3c&e will prove too costly for a customer.
Could save lifting a costly wooden floor.
Nothing wrong with them at all.

 

[DurhamSparky]

wireless stat all the way !!! (most new boilers come with them any way!!)

i will be investing in a decent honeywell one when i get my boiler replaced in june/july as i can then place it in the room i want to controll temp on!! and not the porch where it currently is located...!!

 

[Dunc]

Run a 3C in as others have stated. In my opinion 1.5mm is over kill seeing as how the load is tiny and the allowed VD is 5% in this instance. 1mm is far easier to terminate especially when the connection area is as small as it is on most room stats. Just so you know not all room stats require 3 cores to them as it all depends on whether or not they are relay operated however, in some instance, when fitting wet underfloor heating systems where the room stat is mains powered and has a set back feature the device requires 4 cores. Just another useless bit of information for you.

 

[Stephen Montagu]

Most roomstats require a neutral for the resistor (known as an anticipator) inside it. The resistor makes the inside of the roomstat about 1 degree hotter than outside. This is to compensate for the delay between the set point (temp) being reached and the heating system turning off. If roomstat is set at 20 degres then turns off at 20, the residue heat from heating circuit would raise the temp to 21/22 degres. The anticipator should turn of the heating at about 19 degres if set at 20. 1mm 3C and E is ok for control circuits since they should be protected by a 3 amp fuse. You don't need heat resistant flex to connect to boiler, its not a heating load. If you have never done a heating control system be aware of 'pump over run' control from boiler, you will need a 4 core flex to boiler for this. If you can get to Bedford 'Danfoss' do a one day course free of charge or Honeywell have somrthing similar for £30.