Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws

Install the app
How to install the app on iOS

Follow along with the video below to see how to install our site as a web app on your home screen.

Note: This feature may not be available in some browsers.

armyash

Esteemed
Plumber
Gas Engineer
Subscribed
Oct 13, 2010
2,650
699
113
Kent
Going to this job tomorrow.

The central heating works ok, goes on on and off when it should.

The boiler fires ok when there is a demand for HW but then the rads get hot too.

Apparently it's had a brand new three port put in last week but the fault still continues.

Programmer?

What else could it be?
 
Full three port or just the head? If just the head, replace body
 
  • Like
Reactions: 1 person
I'd look at the 3 port too first, its not uncommon for new parts to be faulty aswell
 
apart from what everyone else has said,have you asked if its a new fault or existing? can only be as already mentioned if recent but if existing last T rule has not been followed
 
  • Like
Reactions: 1 person
I thought the guy only changed the head but he swears he changed the whole thing otherwise that's what i would have done first. I think he's going back today with a new programmer.
 
If you have 240v on white as well as orange with only HW on then double check the wiring. If you don't have 240v on white and it is still passing through the 3 port then he has probably only changed the head.

I have had a few cheap valves pass from brand new as well so it may be down to that.

If it is not circulating through the 3 port then it will probably be piped up wrong, if it is only just showing up after years the chances are someone has fitted a nrv and it's stuck open.
 
  • Like
Reactions: 1 person

Official Sponsors of Plumbers Talk

Similar plumbing topics

We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.