Balancing question

[trickymicky69]

Hi
I have a recently installed system boiler (Worcester Bosch)

When I remove the heads from the TRVs I can get all of the radiators balanced with a 12 degree drop between flow and return - I know some may disagree with the 12 degree drop but my common sense logic tells me that whilst it may be incorrect, the fact the drop is the same across all rads then the system is balanced? All rad temps are pretty much identical as well.

When I fit the heads to the TRVs the house doesn’t get anywhere near as warm, even with them on maximum almost like they are closing too early?
Thanks

 

[BlueLoo]

Hi
I have a recently installed system boiler (Worcester Bosch)

When I remove the heads from the TRVs I can get all of the radiators balanced with a 12 degree drop between flow and return - I know some may disagree with the 12 degree drop but my common sense logic tells me that whilst it may be incorrect, the fact the drop is the same across all rads then the system is balanced? All rad temps are pretty much identical as well.

When I fit the heads to the TRVs the house doesn’t get anywhere near as warm, even with them on maximum almost like they are closing too early?
Thanks

The trv is a dynamic proportion throttling valve.
The lockshield is a static, proportion throttling valve.

The lockshield puts one foot on the throat of the radiator. The TRV puts the other on.

So you've hobbled the system and now it's only doing what you told it to do and that is move slowly.

Read my post history about balancing.

Tl;dr:
Don't unless you have too.

#controversial.

 

[trickymicky69]

I understand what you are saying but - how does the TRV throttle the system if it is set to maximum and the room temp isn’t warm enough?

 

[Madrab]

TRV's have a set temperature range, whereby each number corresponds to a set temp where the TRV will shut down the rad.

Each manufacturers tends to have a slightly different range but they are all usually around -

• 0 = Off * = 5-7°C 1 = 10°C 2 = 15°C 3 = 20°C 4 = 25°C 5 = 30°C

So if the TRV's are the correct one's for the valves and they're set on 4/5 then unless the house is @ 25>30 deg - i.e. feckin roastin' min - then they shouldn't be shutting the rads down.

 

[trickymicky69]

So it might be a dodgy batch of TRVs?

 

[Madrab]

So it might be a dodgy batch of TRVs?

Few question to ask yourself - What make are the TRV's and what their range is. Are they closing down at the temp they should. How warm are the rads actually getting and are they actually heating up properly if they have been 'balanced'. What is the target space temp and is that actually being reached.

the fact the drop is the same across all rads then the system is balanced

Not really - balanced doesn't specifically mean a certain drop across the rad with all the rads being the same - balancing means that all the rads heat up at the same time, regardless of the distance they are from the heat source and once that is achieved, then trying to achieve a specific drop across the rad to maximise the efficiency of heat transfer from the rad into the space it is heating, whilst trying to achieve the lowest possible return temps back at the boiler, maximising condensing (if the boiler is a condensing type).