cold tap (mixer) runs hot

[brett71]

our mixer tap in the kitchen does this but i cant understand why, hopefully someone can explain

we do washing up so have run hot water, then when i rinse with cold after about 20 seconds the water goes hot for about another 20 seconds and then back to cold

this will do this even if i turn the cold tap on after an hour or so.

i have a new sink and tap to fit but would like to sort this out at the same time, but have no idea what the issue is

Brett

 

[AlanE]

Kitchen tap should be fed from water mains so feel the cold water pipe when this happens should be cold in which case tap is faulty.

Otherwise need to know what type of hot water system you have, vented cylinder (has cold water storage tank) or unvented (no storage tank).

 

[HOWEDPLMB]

it could be that some where on your domestic hot and cold system the pipes are to close together allowing heat to transfer to cold from hot pipe or your cold pipe could be to near c/h pipes which will also allow for heat transfer

 

[Grenage]

It's got to be a pipe running close to the central heating, as suggested above. Since it takes 20 seconds, it's probably some distance away from the tap.

 

[brett71]

thanks guys,

it does indeed look like its a CH pipe that is causing this, it hadn't crossed my mind but as i think back it has only been noticeable since the central heating has been switched on, its not a massive problem its only my 2 boys who moan about warm squash