rad getting hot whilst hw is on

[essexboy]

hi can someone tell me why my bathroom rad (1st one from pump?)is hot whilst the hot water is tured on ,could it be something to do with honeywell 4073a motorised valve?

 

[ratonnastick]

its the way you system has been designed some people like to have the towel rail (rad) in bathroom to be on all the time the boiler is running, so it is tied into the hot water (when your ment to have you bath,you get nice warm towels)

 

[namsag]

If it didn`t usually heat up it could be the motorised valve passing slighty allowing just enough water through to heat the closest rad

 

[essexboy]

thanks guys for the reponse ,is there a way i can check the motorised valve?

 

[ChrisR]

Yes. First identify which of the side pipes from the 3 port valve goes to the HW and which the CH. From cold(heating), make the HW be heated. The pipe going to the CH shouldn't get hot.