Atag Efficiency

[wibbit]

The underfloor heating was only and example.

If the Lock Shields on your radiators are such that you don't have a huge flow going through them (or maybe you have smart trv's and don't have all radiators open) you could find a similar issue.

Either way, good luck

 

[lockett]

Good deduction, I will check the lock shield valves and open the trv's to maximum, see if that makes any difference.

 

[cross thread]

Maybe the boiler needs range rating, they come from the factory set quite high output and it may need lowering,benefit of Atag is the warranty so contact your installer with your concerns rather that fiddling with the things .

 

[lockett]

If thing don't improve looks like the path I will take

 

[mcmoby69]

Did your installer flush the existing pipework and radiators?
If not it could be that your boiler return temp is too warm which the boiler senses and assumes that the heating is warm enough, and, shuts the burner off.
They monitor everything electronically and adjust burners, fan speed and pump speed accordingly.
Turn all trv's and lockshield to full, turn room stat and boiler stat up full and run it. See what happens.

You could also have a bypass open somewhere, either automatic or manual.
To test that, turn boiler off and all rad valves. Wait for it to cool. Fire boiler up and see if return pipe gets hot after a while or if it overheats and shuts down quickly.

 

[lockett]

Yes the installer flushed the system. I have opened the lock shields and trv's, l will monitor the flow in and out of the boiler when the heating is turned on in the morning.

 

[mcmoby69]

Feel each radiator at the bottom in the middle. Any cold spots, rad is blocked.
How long was he there for?

 

[lockett]

Radiators all heating as they should, did have to bleed only one, all rest heating evenly.

 

[lockett]

First of all I must thank everyone, exceptional support from all contributors.
After following your suggestions, I think I have discovered the problem. As I said I was going to open all the trv's and Lock shield valves. I monitored the temperature in and out of the boiler (thank you JonathanM for you link). The output temperature was not given the boiler set temperature 60deg, but a lower temperature of around 40 to 48deg. After opening the lock shield valve on the nearest radiator to the boiler the temperature increased to the asked for temperature 60deg. I will do some further tests to confirm this. Unfortunately this radiator is in small toilet that is rarely used, in a cold utility room, so was just set for frost setting on the trv. It would appear for the heating to work I will have to open the radiator vales when I don't need any heating in the toilet or utility room, what a waste of heating. What do you think about insulating the radiator so as not to waste the unwanted heat?

 

[wibbit]

After opening the lock shield valve on the nearest radiator to the boiler the temperature increased to the asked for temperature 60deg. I will do some further tests to confirm this. Unfortunately this radiator is in small toilet that is rarely used, in a cold utility room, so was just set for frost setting on the trv.

I thought most radiators are installed in parallel, however I have seen some images that suggest they may be in series.

I suppose it's possible that this one radiator is in series. I'd want to here others opinions, however if you have access to the pipe work, can you change that one to be in parallel like the rest?

 

[lockett]

Unfortunately l have no access to the pipework, without distroring my laminate flooring.

 

[JonathanM]

After opening the lock shield valve on the nearest radiator to the boiler the temperature increased to the asked for temperature 60deg. I will do some further tests to confirm this.

Do the rest of the radiators get quickly up to temperature now? My whole system gets to 60C in less than half an hour.

 

[lockett]

I think I assumption was wrong about the lock shield valves, the house was not warm when I got up this morning, again house did not warm until midday. Watching the ch temp out, first thing this morning it was showing around the 40-45deg mark most of the time, occasionally reaching it's requested temp of 60deg. Checking the temp now, 1:0pm it's hovering around 50-55deg.
I will have my installer try and figure it out.
Thank's