Switch radiator valves to TRV

[aidangallacher1993@g]

Pls see pics...
Got 10mm copper flow and return pipes, have standard lockshield valves and want to replace to TRVs. Will the one in pic (Screwfix) work? I see it's 15mm but think it comes with a 10mm reducer for the copper pipe...

Also, if I drain my central heating system (as have a few of these to fit while renovating rooms) and don't plan to use central heating can I still shower and run hot water for bath/basin etc? It's a combi boiler and currently on the switch for hot water only, won't switch it to hot water and central heating...
Cheers, Aidan.

 

[Wayners]

Pressurised system on a combi. The boiler circulates the water to keep itself cool through the radiators. So no, you can't use the boiler if you drain the system down.

 

[aidangallacher1993@g]

Pressurised system on a combi. The boiler circulates the water to keep itself cool through the radiators. So no, you can't use the boiler if you drain the system down.

Okay mate cheers for you're reply, don't plan to drain system anytime soon and when fit new TRVs will definitely top PRS up B4 any hot taps/, heating run... Cheers

 

[Harry Bloomfield]

Okay mate cheers for you're reply, don't plan to drain system anytime soon and when fit new TRVs will definitely top PRS up B4 any hot taps/, heating run... Cheers

Best to do them all in one drain down, then install inhibitor solution, rather than run without, or the expense of several bottles of inhibitor..

 

[aidangallacher1993@g]

Yea that's what I was thinking, someone said about radiator inhibitor that I could drain the bathroom towel rad and fill from the top (bleed valve) then that way when central heating next on turn on all rads for an hour to get the inhibitor circulating throughout the system?
Take it if I've got my central heating system drained I can't use my boiler even for bath hot water or could I? Boiler is switched to hot water only, not central heating atm.

 

[ericmark]

I would not think so, the DHW system is basic the same as if not combined into the same case, it still uses a hot coil, may call it a heat exchanger but basic the same thing.

I have found when I have fitted items to central heating, it can take some time to settle, water has air in it which is released when heated, so often needs bleeding a few times.

I had a TRV to fit to mother's hall radiator, the water was clear, and under carpet quarry tiles, so got everything ready and decided to try doing it fast, carpet cleaner ready to suck up any water spilt, I had about a 1-foot wet patch when finished, this house I would not dare try, floors are compressed board, no way would I take a chance it could get wet.

 

[aidangallacher1993@g]

I think I'm holding off on the TRVs for now, plan would be to do all 8 that need doing in one day, drain the central heating, no hot taps on that day, gives me peace of mind. That way when all TRVs fitted I'll add radiator inhibitor through the bathroom towel radiator as bleed valve sits on top so longs the radiator is drained it's quite handy to get the inhibitor around the system. Got two bedrooms to decorate so will shut the flow and return to them drain rad and remove them attach once decorated, house has 10 rads, Reckon if I took 2 rads off to decorate the water pressure I removed from system will be okay while bath's/shower's get run, Central heating won't be used until new TRVs fitted, system will be topped up and rads bled by then new inhibitor etc.
Sorry bit long winded there.

 

[Harry Bloomfield]

That way when all TRVs fitted I'll add radiator inhibitor through the bathroom towel radiator as bleed valve sits on top so longs the radiator is drained it's quite handy to get the inhibitor around the system.

If when a radiator needs bleeding, once all your TRV's are fitted, the system refilled and satisfied yourself there are no leaks - simply close both valve to the radiator, you intend bleeding, remove the complete bleed valve, and funnel the inhibitor in. Replace the bleed valve, open both valves, and bleed.

 

[aidangallacher1993@g]

If when a radiator needs bleeding, once all your TRV's are fitted, the system refilled and satisfied yourself there are no leaks - simply close both valve to the radiator, you intend bleeding, remove the complete bleed valve, and funnel the inhibitor in. Replace the bleed valve, open both valves, and bleed.

Cheers mate, before funneling the inhibitor and two valves shut, drain radiator first so there's room for the inhibitor? How much inhibitor with 10 rads throughout house? Heard mixed reviews on that one

 

[Harry Bloomfield]

Cheers mate, before funneling the inhibitor and two valves shut, drain radiator first so there's room for the inhibitor?

The point was - If the radiator needs to be bled, it's because there is airspace above the water level, if there is airspace, there is space for the inhibitor, so no need to drain any water at all.

How much inhibitor with 10 rads throughout house? Heard mixed reviews on that one

It will indicate on the bottle, but one bottle will be more than enough. Just pour it all in, you cannot really over do it.

 

[aidangallacher1993@g]

The point was - If the radiator needs to be bled, it's because there is airspace above the water level, if there is airspace, there is space for the inhibitor, so no need to drain any water at all.



It will indicate on the bottle, but one bottle will be more than enough. Just pour it all in, you cannot really over do it.

Cheers Harry, appreciate your tips, got one rad off just now to decorate, back on Tomo if not next day, another room to go and I'll get to this, cheers mate