Hi I have a british gas branded thermostat RTS4 I want to change it over to honeywell dt90e Just a little confused with existing wiring and where it would go into the dt90 Currently wired as Grey into N Brown into L Black into 3 Earth into L and 1
Ok. So which colour would go into the dt90 as it labelled abc? And just out of your advice what is the best digital thermostat to go for or is this good?
Brown A Black B. There’s that many stats on the market. What are you looking to gain by replacing the stat. Can maybe advise a bit better with more info.
Accurate temperature The current one i got has got play in it. It quite a few degrees out. Eg if i set it to 20 it probably really is 25 before heating fires up. I hope I explained it correctly
Most stats work the same way. If it’s set to 22 if won’t always go on and off at 22. If it did this it would be constantly be going on and off. So there’s a bit play either side of the setting so it’s not cycling on and off as frequently. If you want a stat with a digital reading then the one your thinking about is fine.
Ok thanks for your help Lastly is there a version of the dt90 stat i can get without battery? So the display works from mains?
You don’t have a mains. You have a Live into the stat from the programmer. A live out from the stat to the boiler. And a Neutral.
Use a terminal strip then cover in suitable tape. There’s lots of battery powered stats on the market that will let you have the digital display. There’s also lots of dial type stats that are suitable for your current wiring.