fitting new heating thermostat

Am I right in saying I will only need to use red and yellow wires for the new thermostat ?

Merry xmas

Sean

Hi Sean

Red would usually be live supply in and yellow the live switch wire back to the programmer, neutral used on the old stat as it had a heater included within the mechanism.

Emgee

A wired Thermostat, how quaint! Only joking, we only switched over to wireless earlier this year when we had a new boiler fitted.

As emcee says, red should be live, yellow with red sleeve switched live to boiler and blue would be neutral on an old style thermostat.

So red to A, yellow with red sleeve to B and terminate the unused blue in an insulate terminal block.

Thanks everyone .

Merry xmas

Sean

Dont forget to conect the green and yellow to the metal box pattress.

David

My recently installed gas central heating has a portable thermostat with a radio link to the boiler. It does however read 2 degrees higher than any of the thermometers I have in the house. I wonder if it has been "adjusted " by the eco-police.

I have the same setting problem I have to set wireless thermostat 2 degrees higher to old style thermometer at the side of it.

David

wonder if it has been "adjusted " by the eco-police.

Well yes to some extent. Modern stats are intelligent (not ). They use a type of fuzzy logic. Old stats had a neccessarily wide hysteresis loop which meant if the stat was across the room from the heat source it took a while to react to the rise in temperature and even when the stat turned off thevtemperature would still climb as the heat source still outputting at that point. New stats predict this effect so will turn the heat of and on a few times before desired temp is reached. this wil vary with the amount of temperature difference demanded by the user. the end goal being not to overshoot required temperature.

Alan

Edited By Norfolk Boy on 25/12/2019 07:59:19