Renewable Heating Hub Heat Pump Forums

Search with Wattson
Forums
Renewable Heating
Air Source Heat Pum...
Vaillant water pres...
 
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!

Vaillant water pressure gauge vs Analogue gauge

 
Page 2 / 2
Air Source Heat Pumps (ASHPs)
Last Post by jeegnesh 8 months ago
21 Posts
4 Users
2 Reactions
3,291 Views
RSS
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 08/04/2025 1:04 pm  

@adamk - Yes they get very close when HP is off within 0.1 or 0.2 once the HP goes on there a difference of 0.4-0.6


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
ReplyQuote
 AdamK
(@adamk)
Reputable Member Member
Joined: 1 year ago
Posts: 222
08/04/2025 1:50 pm  

yeah sounds like its pumping against something. is the whole circuit UFH?



   
ReplyQuote
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 08/04/2025 1:58 pm  

@adamk - Its a huge system, ground floor is predominantly UFH around 100sqm, rest is rads I think 13 of them


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
ReplyQuote
 AdamK
(@adamk)
Reputable Member Member
Joined: 1 year ago
Posts: 222
09/04/2025 9:33 am  

Posted by: @jeegnesh
↑

@adamk - Its a huge system, ground floor is predominantly UFH around 100sqm, rest is rads I think 13 of them

just wondering if the UFH is creating some back pressure and the rad locksheilds are closed down too much so when the pump kicks in its pumping against too much resistance.

 



   
ReplyQuote
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 09/04/2025 10:04 am  

@adamk not sure I want to mess with the lockshields I assume that would mess with the balancing. 

have someone coming next Wednesday to take a look at all the issues. 


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
👍
1
ReplyQuote
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 17/11/2025 4:51 pm  

@adamk yes they equalise once off


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
ReplyQuote
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 17/11/2025 5:02 pm  

As winter is coming back, I can give an update -- so the new installer came months ago and flushed the system and removed the small strainer and instead a regular Y strainer 28mm has been added -- after this the weather was good and so no real testing.  My heating has been running lightly for a month or so and guessing this week it is ramping up.

The good news is after the clean and new bigger strainer my flow rate was touching 2,000 and many months after I just took a look and it still exactly the same figure which suggests the blockage issues are no more.

The pressure gauge still has the same behaviour 1.7bar when off and 1.3 when running this is consistent behaviour, which I still don't know is right or wrong.

Winter 2 - let the games begin again (oh my annual service is due too 🙂 (first one)


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
ReplyQuote
JamesPa
 JamesPa
(@jamespa)
Illustrious Member Moderator
Joined: 3 years ago
Posts: 5123
17/11/2025 5:20 pm  

Posted by: @jeegnesh
↑

The pressure gauge still has the same behaviour 1.7bar when off and 1.3 when running this is constistent behaviour, which I still don't know is right or wrong.

Mine does something similar, I'm not worried about it, I assume it's just dynamic pressure difference due to resistance in system.  Without pressure differences, generated by the water pump, there would be no flow.


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
 jeegnesh
(@jeegnesh)
Estimable Member Member
Joined: 2 years ago
Posts: 100
Topic starter 17/11/2025 6:04 pm  

@jamespa Agreed I don't feel concerned about this, especially as it reverts back, so it can't be leaking out.


13.6kw Solar, 40kw Battery, 10kw Heat Pump and EV Cars


   
ReplyQuote
Page 2 / 2
Forum Jump:
  Previous Topic
Next Topic  
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