TBOE radiators in new build incorrectly piped

[Tea-Break]

There is nothing wrong with TBOE. However, the flow must be the top. BBOE then yes doesn’t matter with by-directional TRVs (Although I always fit TRVs on flow).
It could be the rads are deliberately oversized to reduce return temp and assist with longer periods in condensing mode.
No just noticed it’s a district heating system, so disregard that.
As John.g says BS EN 442 give a delta temp of 50
so there is a design issue here.

 

[Jones82]

Surely it would be an easy job to swap flow and return around as the pipes enter the property or even before? Is the heat exchanger in a cupboard or something, could they cross the pipes there

 

[ImranF]

Surely it would be an easy job to swap flow and return around as the pipes enter the property or even before? Is the heat exchanger in a cupboard or something, could they cross the pipes there

Heat Exchanger unit in store. Yes solution is simple, swap the pipes. The issue I am having is to convince the developer to get the work done.
They are currently saying it does not matter when it clearly does matter.

 

[Deleted member 103244]

If the TBOE is on a one pipe system it matters greatly and will need rectifying Should they be piped on a two pipe system purely to make it easier to adjust the TRV without bending down I doubt it will make a significant difference.

 

[Chuck]

I think that the OP is focusing on the wrong point at the moment. If the radiator is operating with a deltaT of 3°C it will make a negligble difference to the heat transfer whether the flow is top-bottom or bottom-top.

The first question should be, is the system is designed with radiators sized to operate with a flow temperature of 53? If not, that's what needs looking into first.

IMO, in discussion with the developer, the OP should stick to complaining about the performance of the system. E.g. "It takes 2 hours for the heating to raise the temperature in this room from 17 to 19 degrees." or "When the temperature outside is below 5 degrees, the temperature in this room never gets above 19 with the heating on full.", etc. Don't try and tell them how to fix it, that's their problem.

If and when you reach deadlock then is the time to employ your own heating engineer, and you'll need one familiar with district heating schemes, to investigate and report on the problem. They'll be able to confirm whether the system meets the appropriate standards and advise on possible remedies.

 

[ImranF]

Hi, I have started to make a note of how long it takes to heat the living/kitchen dinner where the thermostat is located. This is open plan area 30sq m in L shape layout with large Patio windows. We are on the ground floor as well.

There are two radiators installed in this room.

Today outside temperature is 10 degrees and the room temperature was 17 degree. Heating has been on for 2 hours and the temperature now is 18.5 degrees. Surely that is way too long time and indicates a problem with the system.

 

[ImranF]

Hi, I have started to make a note of how long it takes to heat the living/kitchen dinner where the thermostat is located. This is open plan area 30sq m in L shape layout with large Patio windows. We are on the ground floor as well.

There are two radiators installed in this room.

Today outside temperature is 10 degrees and the room temperature was 17 degree. Heating has been on for 2 hours and the temperature now is 18.5 degrees. Surely that is way too long time and indicates a problem with the system.

 

[rpm]

What about the point raised before, have you addressed them? Have you had your meeting?

 

[ImranF]

Meeting rearranged, I was stuck in Germany with food poisoning. It has been rescheduled for next Wednesday.

The heating company is looking at the radiator specs to check how they should be plumbed. That does not feel me with confidence if you have to look at the manual to know you should not have the return at the top with TBOE radiator.

 

[ImranF]

Engineer came out yesterday as they had to rehang the radiator which was not hanged properly.

Also tightened the bolts which were loose to get rid of the leak in the Heat Exchange Unit.

Regards to the Delta Temperature.
The Exchanger has flow temperature set to 75 degrees. The return temperature using thermal camera is 50 degrees, I assume this is actually much more like 70 degrees as the incoming temperature was read as 53 degrees.

Anyway we still have a lot of air in the system, he said they will powerflush the system.

He is insisting it does not matter if the return is at the top.

Also stated 3 hours to increase the temperature of the room by 2 degrees is due to room size and that we are on ground floor.

After they remove the air from the system I will have to hire someone to get a report done.

I need someone to explain why the return should be at the bottom and what difference will it make to the system.