No hot water open vent glowworm fuelsaverMKII R40

[Bbarclays]

Hi there
Today friend was changing radiator valves, so he drained system, put radiator valves, new radiator.
I notice TRV valve was on cold end- return or out line from radiator.
I asked my friend to relocate TRV valve on inlet side. (when heating started, hot water was coming from white plastic pushfit, I assuming that is inlet, therefore TRV should be there).
He relocated TRV valve in inlet.Then he done something, boiler shut off (overheated?)Then he replaced circulation pump. Then no hot water at all even when heatin is on, and most amazing, plastic pushfit (which was hot and I assume was radiator inlet) became cold and another pipe which was radiator return (copper) and was cold now piping hot!
In another words, hot pipe became cold on that radiator and cold became hot.
I mean cold and hot when we starting heating and system is still cold, therefore obvious where hot water start to flow.
What the heck is going on?
Did he install heating pump in reverse flow?
Please please help

 

[Brambles]

Firstly you need to check / confirm whether or not the TRV’s are bi-directional. If so they can go on either end of the radiator.

The boiler locking out is / was probably a result of an airlock - a result of not properly removing all the air from the system after replacing the radiator valves.

The pump - unlikely that it needed replacing if your system was working yesterday. Only he/she can tell you what they have done with the pump and why.

Probably best not to let your friend loose on your heating system in the future.

 

[Bbarclays]

Firstly you need to check / confirm whether or not the TRV’s are bi-directional. If so they can go on either end of the radiator.

The boiler locking out is / was probably a result of an airlock - a result of not properly removing all the air from the system after replacing the radiator valves.

The pump - unlikely that it needed replacing if your system was working yesterday. Only he/she can tell you what they have done with the pump and why.

Probably best not to let your friend loose on your heating system in the future.

Hi Brambles
Thank you for your letter.TRV is Drayton RT212, which is multi- my bad.
Solved it yesterday myself by putting pump in correct flow direction.
Regarding friend - he is gas safe registered. It was very frustrating two days, I learned how my particular heating system, three port valve , circulation pump etc works, figured out fault and rectified. Also in future do not let my friend to do anything with central heating. (Ironicaly he works for central heating and services boilers on daily duty).
Imagine my frustration...
But after hard study I can yesterday enjoy piping hot radiators and hot water.
Bramley, how would you remove airlock on open vent system?
Also airlock on hot water side.
I notice yesterday airlock, water was coming to AB port, then stuck on B port, which connects to hot water cylinder.(three port Honeywell valve)
Many thanks