REVERSE CIRCULATION

[Agile]

Some might say that there should be a length of pipe before the HW return connection and not just two Tees next to each other!

 

[oilhead]

Having worked on many oil combis where they rely on non return valves to isloate heating during hot water operation, your problem in accepting a nrv would be it failing to operate after a short period. Stick to your guns.

 

[fixitflav]

Hi,

I had an 'S' plan CH system installed by a plumber who was subcontracted to builder. Since it was installed, it has suffered from reverse circulation with the upstairs rads getting hot when the HW is switched on/CH switched off.

I am meeting with both the plumber and builder this week to try to finally agree a way forward and sort this problem. We do know the return pipework has been connected incorrectly beneath the HW cylinder but I'm afraid that the plumber will just propose a non return valve on the radiator return as an easy fix. I'm sure this will fix the problem but I don't want to be bullied into having to accept this 'bodge' solution on what is a newly installed system.

What are the feelings of you guys out there?? What are the problems of having a non return valve fitted, especially in the long term??
Many thanks in advance...

We've already kicked this to death in a thread you started on 27 April.