TBOE radiators in new build incorrectly piped

[ImranF]

Hi everyone,

I am seeking some advice. We moved in last year to a new build flat which has 6 TBOE radiators with TRV's at the top. The new build flat uses a heat exchange unit as it is connected to district heating system. All pipework is behind the plasterboards and run up in the ceiling.

I have noticed that the return is actually at the top of the radiators and the feed is from the bottom. The radiators do get hot but take around 30 to 40 minutes to get hot. I have also issues with lots of air in the system.

I know this is incorrect so logged this as a defect. The engineers who fitted the system stipulated that it did not matter which way around the pipework was fitted as the TRV was bi directional. So the developer will not charge the pipework around as the radiators get hot.

I have even asked NHBC and they have stated that as long as the radiators get hot it does not matter whether the pipework was fitted incorrectly.

Can anyone clarify why the feed should not be at the bottom and what problems can it cause. Would my heating work more efficiently if radiators were plumbed in correctly i.e fed from the top?

Also can anyone suggest how I could some how get the developer to change their minds. Maybe possibly by getting independent report.

Many Thanks in advance for any advice provided.

 

[ShaunCorbs]

Yes it matters return should be at the bottom so when the water cools it flows into the return

 

[Chalked]

As Shaun says, it does matter. But it will still get hot. If it is taking that long, ther is a different problem .

 

[ImranF]

Basically assume it's inefficient. Engineer used thermal camera and you can clearly see the temperature difference between incoming and return being on 3 degrees. Incoming was 53 and return was 50. Bottom of radiator was 40 degrees. It makes more sense to return the cooler water than the hotter water.

Assume this also will cost me more money in my heating bills?

 

[Riley]

If you only have a 3°C difference from flow to return then there is a chance that your boiler isnt condensing properly either

 

[SimonG]

It will be a hiu.

Chances are you have another issue.

 

[snowhead]

Is the issue just the time that the radiator takes to heat up or is the room taking a long time to warm up as well?

 

[John.g]

Basically assume it's inefficient. Engineer used thermal camera and you can clearly see the temperature difference between incoming and return being on 3 degrees. Incoming was 53 and return was 50. Bottom of radiator was 40 degrees. It makes more sense to return the cooler water than the hotter water.

Assume this also will cost me more money in my heating bills?

The flow should be from top to bottom, the bi directional TRV can be at either end.
You might have a very cold house/room as rads now a days are rated as "50 deg" rads which is (flowtemp+returntemp)/2 - 20. your rads are "32 deg" rads, which will only emit 56% of their rated output except that they are over sized to take this factor into account.

 

[ImranF]

Is the issue just the time that the radiator takes to heat up or is the room taking a long time to warm up as well?

Rooms take a long time to warm up. I believe the developer needs to resolve and should get it working as specified according to their design.
Also this should in turn reduce the heating bills.

Thanks for all your responses. I have arranged another meeting with the developers to discuss.

 

[snowhead]

Are there other flats in the development, have you spoken to the occupants about thier heating if so?