Renewable Heating Hub Heat Pump Forums

Search with Wattson
Forums
Renewable Heating
Air Source Heat Pum...
Balancing a low los...
 
Notifications
Clear all

Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!

Balancing a low loss header/buffer tank on a Grant Aerona 2 13kw r32 system

 
Page 2 / 2
Air Source Heat Pumps (ASHPs)
Last Post by Uk_pete_2000 2 years ago
15 Posts
2 Users
0 Reactions
3,937 Views
RSS
 Uk_pete_2000
(@uk_pete_2000)
Trusted Member Member
Joined: 2 years ago
Posts: 83
Topic starter 26/11/2024 12:37 pm  

@jamespa 

We can ignore the house heating load. Yes it's low on the ch side, it only needs 23° - 25° in the ufh to get to 19° in the room.

Grant ashp lowest setting is 23°, so for the time being we can ignore the wc curve and just set it to a temp. In our case we are having to set it to 28° - 30° to get ch side to the correct setting.

We have run through all the settings from setting the grant to its lowest, mid and highest flows and then taking the pumps though the 6/7 settings they have. Allow it to settle and check temp and nothing seems to make any difference.

I am now running the system on grants highest setting and two of the pumps are turned off. HP set tp 30°. This is what we get ORDER ABCD

20241126 113411


   
ReplyQuote
JamesPa
 JamesPa
(@jamespa)
Illustrious Member Moderator
Joined: 3 years ago
Posts: 5316
26/11/2024 1:56 pm  

Not sure exactly what the picture shows as there appear to be 8 readings.  If its the bottom temp readings that are of interest, the they seem to be 29.2, 28.3, 27.5, 19.2 so A-> C now a bit less than 2.  Isn’t this an improvement?  D seems to indicate deltaT across UFH now 8C, which at current OAT seems quite high, so may be a problem when OAT drops but equally might not matter.  However thats perhaps because the flow rate is low as you have only 1 pump running.

TBH I think you have run through all the simple options and Im not sure I can add much more.  I have the impression you understand the principles, so its a bit of a case of play and see what happens, or wait until someone comes along with a magic solution, if indeed there is one without spending any significant money.


4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.


   
ReplyQuote
 Uk_pete_2000
(@uk_pete_2000)
Trusted Member Member
Joined: 2 years ago
Posts: 83
Topic starter 26/11/2024 2:36 pm  

@jamespa sorry my bad. Yes it's the middle readings that have a temp probe. The are ordered as ABCD

I've just turned on all the pumps and set them to high load and noticed that B went down and D came up. So the CH is taking from the tank. 

Once it stopped changing so much I lowered the speed of the CH pumps to 1 and will check again.

(I'm sure I had the HP set at its highest speed, but I didn't turn off any pumps last time I tried.)

If the above goes back to major differences then I'll just run the one pump tomorrow and if if things settle down. 



   
ReplyQuote
Page 2 / 2
Forum Jump:
  Previous Topic
Next Topic  
Topic Tags:  Grant Aerona 3 13kw (1) ,
Share:

SPONSORS

Join Us!

Installer Finder

Degrees of Separation

Latest Posts

SPONSORS

Click to access the login or register cheese
Protected By
Shield Security PRO