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Looking to move house, many have old boilers fitted, and I will want to in fullness of time upgrade, but the boiler will be changed by some one registered as gas safe, but rest done by myself, so would prefer to fit TRV's and new lock shield valves before the boiler so all ready for new boiler.
However not sure what will happen if I fit TRV's to old boiler? Last house TRV's fitted upstairs but not on ground floor and the Myson fan assisted radiator has no lock shield valve so always a flow, some boilers have a by-pass inside boiler, some need it exterior, so not keen on fitting a by-pass valve which may then need removing once boiler changed.
Also not sure how TRV's will work with a non modulating boiler? I know how they work with modulating boiler, but if the boiler is not running I would assume the valve will open more and more until fully open, then when boiler runs radiator will heat up completely before valves can close again, this of course still happens with a modulating boiler when turned off over night, but on switch on house is cold so there is time for valves to shut. But with a wall thermostat one would expect boiler to run at least once an hour, so will fitting TRV's end up increasing the hysteresis.
So should they be left wide open until new boiler fitted, i.e. don't fit heads, and what about the kitchen, if I fit a Myson kick space in kitchen, will this work OK once boiler changed. Or will the fan stopping cause the modulating boiler to throttle back, even when other rooms not to temperature, can I actually fit a TRV to a Myson? I know fan will not kick in until warm enough.
Just trying to work out order of events once I move, would be good to drain system and fit all TRV's and new lock shield valves before we move in so no furniture in the way, but likely I will not be able to wait for a boiler to be changed before moving in.
However not sure what will happen if I fit TRV's to old boiler? Last house TRV's fitted upstairs but not on ground floor and the Myson fan assisted radiator has no lock shield valve so always a flow, some boilers have a by-pass inside boiler, some need it exterior, so not keen on fitting a by-pass valve which may then need removing once boiler changed.
Also not sure how TRV's will work with a non modulating boiler? I know how they work with modulating boiler, but if the boiler is not running I would assume the valve will open more and more until fully open, then when boiler runs radiator will heat up completely before valves can close again, this of course still happens with a modulating boiler when turned off over night, but on switch on house is cold so there is time for valves to shut. But with a wall thermostat one would expect boiler to run at least once an hour, so will fitting TRV's end up increasing the hysteresis.
So should they be left wide open until new boiler fitted, i.e. don't fit heads, and what about the kitchen, if I fit a Myson kick space in kitchen, will this work OK once boiler changed. Or will the fan stopping cause the modulating boiler to throttle back, even when other rooms not to temperature, can I actually fit a TRV to a Myson? I know fan will not kick in until warm enough.
Just trying to work out order of events once I move, would be good to drain system and fit all TRV's and new lock shield valves before we move in so no furniture in the way, but likely I will not be able to wait for a boiler to be changed before moving in.