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Still comes back to: what was the design flow temperature for the heat loss?
And how come your designer / installer isn't sorting all this for you?
Also
The u'floor heating shouldn't be controlled by that, you really shouldn't be altering that on a regular basis, it should be set at it's design temperature.
What do you hope to achieve by altering it?
Doesn't make sense.
Your house will take the energy it needs depending upon the heat losses, which is factored by the temperature in the rooms you are heating and the adjacent rooms and the outside air.
I know from your other post you've got problems with you heat source efficiency. However you need to consider all sorts of things, like if you turn the heating down in a room (set back) then it will take more energy to heat up. (it in the order of an additional 22W/m2)
Lets say your accumulator is at 70° and you let it drop to 40°, then a 30° drop on a 1000 ltr accumulator that's only 35kWh of heat storage, and if you're tapping off halfway up then that's even less energy stored. (volume AND temperature gradient)
To answer your original question though, from the photo it looks like a trv with a probe, with all those loops, it would better to swap that for a 3 port mixing valve with a thermostatic head.
(You'll need a bypass on the main circulation pump)
Don't see any flow gauges on the u'floor heating loops though so how have the flow rates been set up?
View attachment 18334
That's the purpose of the mixing valve, it should quite happily cope with a supply temperature of 85°, and blend it down to the DESIGN flow temperature.
If you've set the TRV to 20° then the rooms will never heat up and the u'floor heating will be pumping all day to no avail, you need a flow temperature greater than the room temperature, once again it comes back to: What is the design flow temeprature of the u'floor heating - go back to the original design documents and set the trv at that and let it do its job.
Also if you're having all these issues then:
1) it clearly wasn't fully commissioned in November
and
2) You really need to get the designer and installer back to properly commission and configure the whole system..
Or were you the designer, and the "plumber" is just doing what you told him to do?
- Note not all plumbers are heating engineers.... and as an aside we always leave the customer with a 'retainer' until we've finished, commissioned and certified ALL the work.
And how come your designer / installer isn't sorting all this for you?
Also
The u'floor heating shouldn't be controlled by that, you really shouldn't be altering that on a regular basis, it should be set at it's design temperature.
What do you hope to achieve by altering it?
Doesn't make sense.
Your house will take the energy it needs depending upon the heat losses, which is factored by the temperature in the rooms you are heating and the adjacent rooms and the outside air.
I know from your other post you've got problems with you heat source efficiency. However you need to consider all sorts of things, like if you turn the heating down in a room (set back) then it will take more energy to heat up. (it in the order of an additional 22W/m2)
Lets say your accumulator is at 70° and you let it drop to 40°, then a 30° drop on a 1000 ltr accumulator that's only 35kWh of heat storage, and if you're tapping off halfway up then that's even less energy stored. (volume AND temperature gradient)
To answer your original question though, from the photo it looks like a trv with a probe, with all those loops, it would better to swap that for a 3 port mixing valve with a thermostatic head.
(You'll need a bypass on the main circulation pump)
Don't see any flow gauges on the u'floor heating loops though so how have the flow rates been set up?
View attachment 18334
That's the purpose of the mixing valve, it should quite happily cope with a supply temperature of 85°, and blend it down to the DESIGN flow temperature.
If you've set the TRV to 20° then the rooms will never heat up and the u'floor heating will be pumping all day to no avail, you need a flow temperature greater than the room temperature, once again it comes back to: What is the design flow temeprature of the u'floor heating - go back to the original design documents and set the trv at that and let it do its job.
Also if you're having all these issues then:
1) it clearly wasn't fully commissioned in November
and
2) You really need to get the designer and installer back to properly commission and configure the whole system..
Or were you the designer, and the "plumber" is just doing what you told him to do?
- Note not all plumbers are heating engineers.... and as an aside we always leave the customer with a 'retainer' until we've finished, commissioned and certified ALL the work.
