Renewable Heating Hub Heat Pump Forums

Search with Wattson
Forums
Renewable Heating
Air Source Heat Pum...
Newbie: utterly con...
 
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!

Newbie: utterly confused with my Mitsubishi Zubadan air source heat pump running on 55C set flow temperature

 
Page 16 / 16
Air Source Heat Pumps (ASHPs)
Last Post by Sandman1600 12 months ago
183 Posts
11 Users
56 Reactions
51.4 K Views
RSS
 Sandman1600
(@sandman1600)
Trusted Member Member
Joined: 2 years ago
Posts: 72
Topic starter 16/10/2025 11:09 am  

@davidnolan22 Hi..! We've only just turned on the heating again following the summer but it's not overly concerning right now. It's cycling a little but we're getting COPs of between 3.5 and 4. I'll keep my eye on it as the weather gets colder.



   
ReplyQuote
dgclimatecontrol
 dgclimatecontrol
(@dgclimatecontrol)
Estimable Member Member
Joined: 1 year ago
Posts: 73
16/10/2025 11:23 am  

Posted by: @sandman1600
↑

Hello! I’m new here and looking for a bit of advice. I’ve been waking at 4 in the morning stressing about our energy usage, googling until my eyes cross and this eventually led me here.

We’ve just moved from a Grant oil boiler to a Mitsubishi Zubadan ASHP. We have Polypipe underfloor heating throughout the whole house. The only radiator is a towel rail in the bathroom.

With the old boiler we’d have a setback temperature 2 or 3 degrees lower than the desired temp and just have the rooms heating when we wanted them to be warm. The manifold temp was set to 50 upstairs and 53 downstairs (concrete pad and takes longer to heat). 

I understand that the recommended setting for ASHP is just to have them on continually so we’ve now just set a target temperature for each room with a 0.5 degree setback.

However, since the HP was installed we’ve seen electric consumption pretty much quadruple and I’m worried we’re not setting something correctly. This week has been cold so maybe this is causing extra pressure.

The installers set the flow temp to 55 degrees. I immediately lowered this to 50 as I understood that an air pump needs to be lower to benefit from the efficiency. I’m now thinking it’s just running a lot of the time and electricity usage is therefore rocketing.

Is it better to set it to a 55 degree flow temperature and let it heat up rooms a little quicker and not be heating as continually. Or is it better to be running more at a lower temperature?

Does that make sense? If there’s any other information I can supply, I’d happily do this.

 

 

  It'll bring on electric back up heaters if at 55C as they'll work quicker in the winter. Not sure about old ME units but Daikin had a 6 or 9kW back up! often working to start the system off then being taken over by the HP.  You need it setting to 40C max and leave it on, if bills high or not warm enough its the installation.

 



   
ReplyQuote
 Sandman1600
(@sandman1600)
Trusted Member Member
Joined: 2 years ago
Posts: 72
Topic starter 16/10/2025 11:33 am  

@dgclimatecontrol Thanks... this was resolved back in March/April.



   
ReplyQuote
Page 16 / 16
Forum Jump:
  Previous Topic
Next Topic  

Currently viewing this topic 4 guests.

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