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Air in my radiators
Hi all,
I had an ASHP installed back in June and I have been really happy with the performance, especially over the recent cold snap (averaged 26kWh electricity use a day for our 132m2 house). However, the radiators at the top of the house need bleeding every couple of weeks - is this normal? Where is the air getting in?
We have a mitsubishi ecodan 8.5kW.
Cheers
Gavin
Posted by: @gfletcherHi all,
I had an ASHP installed back in June and I have been really happy with the performance, especially over the recent cold snap (averaged 26kWh electricity use a day for our 132m2 house). However, the radiators at the top of the house need bleeding every couple of weeks - is this normal? Where is the air getting in?
We have a mitsubishi ecodan 8.5kW.
Cheers
Gavin
I assume that you are bleeding the air from the radiators, but are you also topping up the water in the system?
One reason could just be air in the system collecting at the highest point.
If the problem persist after bleeding and topping up, then suspect a water leak somewhere. Monitor the system pressure over a period of time, since a falling pressure could indicate a leak somewhere.
Hi Derek,
Thanks for the reply. Yes, I am topping up after bleeding. The pressure doesn't drop until I bleed the rads - but since installation I have been having to bleed and then top up every 2-4 weeks.
So presumably it is sounding like a leak somewhere - I'll keep monitoring and contact the installer if it persists.
Cheers
Gavin
Posted by: @gfletcherHi Derek,
Thanks for the reply. Yes, I am topping up after bleeding. The pressure doesn't drop until I bleed the rads - but since installation I have been having to bleed and then top up every 2-4 weeks.
So presumably it is sounding like a leak somewhere - I'll keep monitoring and contact the installer if it persists.
Cheers
Gavin
I am assuming that you did not run the central heating until the weather turned cooler. The fact that the pressure does not drop in normal operation, would indicate that you do not have a leak.
Do you get a 'tinkling' sound when the water is being pumped around the system? Air can be trapped in sections of the system when it is filled, and it can take some time for this air to accumulate in places where it can be removed easily.
Do you have any air release vents on your system? They will possibly be a small brass cylinder, often with a red plastic cap on the top. If you find any gently loosen the red cap to see if any air comes out.
If you Google 'Air Release Valve' it will give you some idea what to look for.
Thanks for the additional info - yes, some small tinkling noises, and yes, only started using properly at the start of Nov. We do have air release valves. I'll keep an eye on it.
Cheers
Gavin
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