Air in towel radiator

[Sammy1]

Thanks kop. Which boiler should we have had? Prior to this we had a standard boiler & hot water tank (not pressurised system) & had no problems. We went for system as we were told it was better for 2+ bathrooms (we have 2 bathrooms at the moment). We were told our old boiler probably couldn’t handle the underfloor heating. So if we get another expansion vessel fitted is this enough? We can lag the visible pipework ourselves, under the floors is a bit tricky now. Is there anything else that needs changing? Is the likely cause of the air ingress a leak or is there anything else we could do to try to stop the air getting in?

Yes, the work is completed & there’s space in the garage for another expansion vessel. The water tank was originally upstairs in the airing cupboard, now moved to the internal garage to allow stairs to be built to the loft. The boiler before & now is in a kitchen cupboard (no top & bottom to the cupboard).

 

[king of pipes]

What you have been told is correct a sealed system boiler and unvented cylinder is the best choice for your property you're boiler is not necessarily wrong it's not unusual to use a system boiler but it needs piping a different way , you will need a extra expansion vessel to accommodate the volume of heated water in the system, the insulation needs doing just do what is visible and easy to access I would get this completed first fit the aav's, future improvements can be made if necessary.

 

[John.g]

There seems to be 2 x red exp. vessels and 1 x white, one red is adjacent to the boiler?, what volume is this.
You can tell easily if the installed exp. volume is sufficient by turning on all heating systems and noting the boiler pressure when all systems hot, if not > 2.5bar then OK from a expansion point of view but maybe other reasons for installing extra one?.
Can you also post a close up photo of the UPM pump, when its running, don't know if its running on one of its manual modes or is PWM controlled.

 

[Sammy1]

What you have been told is correct a sealed system boiler and unvented cylinder is the best choice for your property you're boiler is not necessarily wrong it's not unusual to use a system boiler but it needs piping a different way , you will need a extra expansion vessel to accommodate the volume of heated water in the system, the insulation needs doing just do what is visible and easy to access I would get this completed first fit the aav's, future improvements can be made if necessary.

Thank you. What other improvements would you recommend? And how to we fix this annoying air ingress?

 

[king of pipes]

I'll go into it later I'm now got to work regards kop

 

[king of pipes]

There seems to be 2 x red exp. vessels and 1 x white, one red is adjacent to the boiler?, what volume is this.
You can tell easily if the installed exp. volume is sufficient by turning on all heating systems and noting the boiler pressure when all systems hot, if not > 2.5bar then OK from a expansion point of view but maybe other reasons for installing extra one?.
Can you also post a close up photo of the UPM pump, don't know if its running on one of its manual modes or is PWM controlled.

???

 

[Sammy1]

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There seems to be 2 x red exp. vessels and 1 x white, one red is adjacent to the boiler?, what volume is this.
You can tell easily if the installed exp. volume is sufficient by turning on all heating systems and noting the boiler pressure when all systems hot, if not > 2.5bar then OK from a expansion point of view but maybe other reasons for installing extra one?.
Can you also post a close up photo of the UPM pump, when its running, don't know if its running on one of its manual modes or is PWM controlled.

The photos of the red ones are not my house. Pressure does not go over 2.5. What is the UPM pump? The black box near the water tank?

 

[Sammy1]

I'll go into it later I'm now got to work regards kop

Thank you

 

[John.g]

The photos of the red ones are not my house. Pressure does not go over 2.5. What is the UPM pump? The black box near the water tank?

Apoligies, the red ones are atypical as shown by KOP.

2.5bar is OK for the moment as long as you don't install any more rads etc.
Re Air venting, when you vent the air, then theoretically, if you don't top up the system, if air is entering the system the pressure should build up again, if it doesn't then perhaps air still in the UFH loops even though this might be unlikely since last October, anyway, after the next venting do not top up except that the pressure is excessively low and see what happens.

The Pump is on the UFH manifold as shown, you might post a close up photo of it when running to show the LEDs.
Also if you can see the UFH manifold, the flow rates for each loop and the manifold flow and return temperatures, if available.

 

[king of pipes]

Thank you

One other thing to try is tie wrap a plastic bag on the end of the safety valve of the boiler for 24 hrs run the system heat the water and just monitor if any water is in the bag ? I am working on a large 5 bed house on a insurance job this is a more typical install I have to add I didn't install it but I know the Engineer who did

 

[milleniumaire]

"We also had underfloor heating installed in our kitchen, the manifold is in the garage under the house. "

I thought it was necessary for a UFH manifold to be installed ABOVE the UFH pipes that it supplied? Usually, the manifold has an auto air vent, but if this is below the underfloor heating, it wouldn't have any effect as air rises to the highest point, possibly to the top of the towel rails.

I assume the affected towel rails are at the highest point in the heating system?

What would happen to an auto air vent on an UFH manifold that was installed lower than the UFH? Is it possible air could get into the system? I suspect not, but this is the only thing that jumped out at me regarding your setup.

 

[John.g]

Some towel rads also have electric heating elements which have been known to draw air in via the rubber gaskets.

 

[ShaunCorbs]

Aslong as it’s purged of all air the ufh will work fine if the pipe is above the manifold

 

[Sammy1]

Aslong as it’s purged of all air the ufh will work fine if the pipe is above the manifold

Thanks all, after letting the air out of the towel rails several more times the problem seems to have resolved. I think it may have been air trapped in the system from the installation but will keep an eye on it.

 

[John.g]

Thanks all, after letting the air out of the towel rails several more times the problem seems to have resolved. I think it may have been air trapped in the system from the installation but will keep an eye on it.

There have been numerous posts about air collecting in towel rails, is it because the top(s) of the towel rails are generally higher than any other rad top(s)?.

 

[Chuck]

There have been numerous posts about air collecting in towel rails, is it because the top(s) of the towel rails are generally higher than any other rad top(s)?.

Seems plausible to me. Another, not mutually exclusive, possibilty is that the towel-rail design means that a relatively small amount of air results in a cold 'top rail' and people notice this when they put the towel on or take it off.

 

[Lou]

(Just bumping a few older threads, they will drop off what is new soon)

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