Difficulty rating : Changing a TRV?

mjd

mjd

Permabanned
Joined
21 Oct 2002
Posts
1,074
Location
Llanelli, S.Wales
I need to replace the TRV on the radiator in our kitchen. Our collie chew the thing to bits last year, and I'd like to replace it before the winter.
The rad is next to the back door and there is a drain point in the pipework immediately feeding the rad.
All existing TRVs are Siemens, so I plan to replace with the same or at least similar. Boiler is a Worcester 28si II if that's relevant.
Also during one of BG's weekly visits a year or so ago, when the boiler was on the blink, I believe the engineer drained the system, and subsequently I suspect there is no inhibitor in the system anymore.

So just how difficult is the procedure of fitting a replacement TRV?
and given I am draining the system, is it straight forward to add an inhibitor? (I'm assuming this goes in first)
 
:p

Just went to have nose and sure enough, it came off with a quick twist.
Wish I'd asked this question sooner.

Can I still add an inhibitor without draining down completely?
 
Yes, just turn of the trv & valve each end of the radiator, remove the complete vent plug or blanking cap if there is one, some inhibitor comes with a flexy spout you can pour it in.

You might need to drain the radiator a bit to get all the inhibitor in.

If combi might need to add a bit more water, & get pressure back up & also bleed any air.

Unfortunately I'm not familiar with Worcester 28si II charging the system.
 
Last edited:
That's great - thanks for the info.
The boiler has a filling loop, so should be straight forward.
 
If you have a heated towel rail in you ch system, it's easier to add the inhibitor via that, turn the valves off, remove blanking plug & pour it in.
 
Last edited:
Back
Top Bottom