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!
System pressure dropping on my Ecodan ASHP system
I have an Ecodan ASHP, due to some building works the hot water cylinder was relocated and some legs have been run for 3 more radiators which have yet to be fitted.
Hot water has been fine since the relocation of the cylinder around 4 weeks ago. This weeknd I put the heating on, all was fine but next morning when the hot water cycle ran before the heating comes on there was a U1 fault which I believe is a low pressure fault.
So I filled the system to about 1.7bar when heating was on and bled the radiators. I manually put water cycle on and cylinder had hot water.
Next morning after heating had been on before same problem. It seems that when I fill the system within about 30 mins pressure drops to 1 bar or less, however all rads are nice and hot.
Any ideas? Thanks.
@spacebiscuit - this is an interesting question, why does an ASHP circuit need to be pressurised in the first place? I can't be, as it is with a traditional car radiator system, so the water can get to a higher temperature without boiling, since ASHPs don't get anywhere near those temps. I have a very very small leak, at least I assume it is, in my primary circuit, that causes the pressure to drop very slowly (over days if not weeks) and yet the system seems to run the same whatever the pressure, as long as the circuit has fluid in it, which it does. Maybe the pressure is there to stop negative pressure that would perhaps allow air to enter? Does anyone know the answer?
Midea 14kW (for now...) ASHP heating both building and DHW
Hello i am an ASHP Engineer and new to this group. Ecodan U1 code is said to be high pressure fault,which is cause by abnormal water flow on the primary circuit. I recommend get ASHP engineer to come have a look.
- 26 Forums
- 2,698 Topics
- 63.3 K Posts
- 838 Online
- 7,106 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
RE: Electricity price predictions
Chinese manufacturing has the ability to be very good q...
By Majordennisbloodnok , 4 hours ago
-
RE: Air source heat pump roll call – what heat pump brand and model do you have?
Forum Handle: GotGordon Manufacturer: Samsun...
By Gotgordon , 15 hours ago
-
RE: Summer heat is becoming the new winter cold in the UK. What are you doing about it?
@ian33a I am not easy with sleep either unfortunately…....
By MK4 , 16 hours ago
-
RE: Renewables uptake near you
In a village of under 40 houses...Conservation Area. I'...
By Tim441 , 1 day ago
-
RE: Home Alone with Home Assistant (previously A Beginner's Guide to ASHP Monitoring)
Great news, @bontwoody.
By Majordennisbloodnok , 1 day ago
-
Haier R290 Super Aqua Monobloc. Output capacity tables.
As I mentioned in my introduction post, I've been consi...
By Singlespeed , 1 day ago
-
RE: Air to air bus grant installer anywhere
I am consistently told by aircon folks (ie air/air) tha...
By EtchedPixels , 2 days ago
-
RE: What is possible with FIT, SEG, Hate Pumps and Batteries?
Thank you, everyone, for your replies. Our FIT provid...
By ian33a , 2 days ago
-
@mk4 And of course, the panels are less productive due ...
By Toodles , 2 days ago
-
RE: GivEnergy inverter tripping due to over-voltage?
I'm trying to get clarity on exactly when the inverter ...
By Tim441 , 2 days ago
-
RE: Samsung Heat Pump – Can't Activate TW2 Pipe Sensor (for Delta T Control)
Autocorrupt seems to be working overtime.
By Majordennisbloodnok , 2 days ago
-
RE: Vehicle-to-Home with a Heat Pump: Is the Technology Ready and Which EV Should I Buy?
I looked into that wallbox a bit more off the back of t...
By Majordennisbloodnok , 3 days ago
-
RE: Say hello and introduce yourself
@jandp awesome system I hope it works out well.
By Judith , 3 days ago
-
RE: Surface mount or bury primaries for heat pump installation?
@bobflux That's the stuff. The installer recommended tw...
By tomasmcguinness , 5 days ago



