Navitron Renewable Energy and Sustainability Forum

HEAT PUMPS & Geothermal Energy => Heat Pumps => Topic started by: chris wills on November 09, 2019, 11:40:41 AM



Title: Buffer tank fill levels?
Post by: chris wills on November 09, 2019, 11:40:41 AM
Just wandering how full should my buffer tank be for my ASHP?
As I have had some maintenance done over the past few weeks and lost some of it probably, should it be full to the top or something else?
(https://i.postimg.cc/HVYzZ1B9/B159-B31-A-802-F-4-C7-F-B42-B-10-EE3-A7-AE6-D7.jpg) (https://postimg.cc/HVYzZ1B9)

It's a 200 litre cylinder, should it be full to the top?


Title: Re: Buffer tank fill levels?
Post by: benseb on November 09, 2019, 04:36:43 PM
Should be completely full with any air bled from the top.


Title: Re: Buffer tank fill levels?
Post by: chris wills on November 09, 2019, 05:14:12 PM
That makes sense, I'll top it up


Title: Re: Buffer tank fill levels?
Post by: Nickel2 on November 10, 2019, 09:15:43 AM
Remembering to take expansion into account...


Title: Re: Buffer tank fill levels?
Post by: chris wills on November 10, 2019, 10:31:46 AM
I have an expansion vessel in line.
Any advice?


Title: Re: Buffer tank fill levels?
Post by: rogeriko on November 10, 2019, 09:09:47 PM
Thats a pressurised system buffer. It should have a good 1.5 bar pressure in it. I suggest you call a plumber who can work on pressurised systems and get him to check it out before something expensive gets damaged.


Title: Re: Buffer tank fill levels?
Post by: chris wills on November 11, 2019, 12:42:05 PM
should I top up when all the rads are open so the water is flowing into them, to see how much the tank needs to be topped up by?
I don't think there is enough coolant in the system.
The ASHP comes on every 15-20 mins, is that normal?


Title: Re: Buffer tank fill levels?
Post by: JohnS on November 11, 2019, 08:27:57 PM
Top up the pressure
Bleed the radiators
Top up again
Repeat as necessary

Best to do it with the system off.  Not sure if that is to prevent the risk of scalding water squirting out or of sucking air in if the pump is installed on the return side and thus could be more suction than push.  But generally recommended.