drayton RTS8combistat

[suffolklad]

hi all i fitted the above room stat to my worcester 28si been working for last two weeks but lately ive noticed hearing like arcing sound from stat for a little while as it switches ,i didnt notice it when it was first fitted . its wired correctly using 0.75 flex , 3 wire connection as per instructions . i took stat case off to look what happens and i could see little arcs as the switch tried to seperate . QUESTION IS SHOULD THIS HAPPEN. i am thinking that perhaps this is not good for the boiler if its not switching correctly, is their a set time that it should take for it to switch?. any help most welcome paul

 

[Steve3948]

Have you connected a Neutral to this thermostat.


I would not say 0.75mm² flex is correct wiring for a thermostat, but then that's another story.

 

[suffolklad]

well i asked on here and thats what i was told before i fitted it it is only a 3 amp circuit

 

[Steve3948]

Normally the thermostat is not near the boiler or controls, so will need to be wired through the property, in this case 6243Y 1.0mm² or 1.5mm² would be used which has a bare cpc.
This is the type of cabling used for fixed wiring within a domestic dwelling.

Did you use a 3 or 4 core flex ? cabling should contain an earth even if not used at the thermostat.

Other than your arcing sound, has the thermostat been operating correctly ?
Have you had long periods of the heating being on followed by long periods of the heating being off, if so is the neutral connected both ends.

It could just be the way this thermostat works, I always use Honeywell, but then that's a personal choice.