Installing TRV valve to radiators

[mobily]

Hey all,

I have a sealed heating system and looking to install a TRV valve to 2 bedroom radiators as in the winter the rooms get too hot. I would also like to replace some radiators at the same time.

The sealed system was recently installed due to huge issues experienced previously with the vented system with a massive build up of sludge in the pipework and radiators. It took months of investigation, drain downs, flushes and new pipe work to get the system to a stage where all radiators were getting hot.

My questions are:

1. Do I need to drain down the system to install the TRV or can I isolate the radiators in some way?

2. How do I go about repressurising the system afterwards? I am guessing by the re-filling loop next to the expansion chamber?

3. Will the system need rebalancing? This is my main concern as it has taken a number of years to sort out the heating and I don't want to muck it up!

4. Will I need to include inhibitor when refilling?

Many thanks in advance

 

[mobily]

Hi all,

I have received a quote from a plumber of £100 to supply and fit 2 TRV valves or £80 to fit them if I supply them.

Is this a good price? I am thinking of replacing the radiators downstairs as well as they are only single panel and quite old. I am presuming that if a drain down is required the cost of sticking a new radiator on as well wouldn't be too much more.

 

[longdogs]

If, as you say, the downstairs rads are quite old then it might not be possible to get an exact replacement resulting in having to fit either extensions (not a great idea, they always seem to leak after a time) or some extra pipe work. So it might not be a case of just swapping one rad for another. With all the problems you have had I would suggest getting the plumber to do the work- it is then his responsibility to get it all working again. And, £100 seems like a fair price.

 

[mobily]

I've had a revised quote of £180 to fit 2 TRV valves and replace 3 radiators if I supply the valves and radiators.

I will check the sizes tonight and see if I can get a like for like replacement.

If I am going from single panel to double panel would this be a problem?

 

[Armo74]

Why do you want double panel rads? Are the current rads not sized correctly so not heating the rooms sufficiently? Do they have convection fins? New radiators are more efficient and will more than likely give off a higher heat output than your older ones anyway.

 

[mobily]

I just assumed (incorrectly I think) that double would be better. The reason for changing them is they are very old and starting to look a bit tatty. They have also been a magnet for sludge in the past and not heated up properly.

Looks like single radiator with fins would be fine!

Having thought about it £180 to replace 3 radiators and install 2 TRV valve seems like decent value. I would normally try doing it myself but I've had so many issues in the past I think instructing a professional is the more prudent approach. At least if something godes wrong they need to sort it out!