Weather compensatio...
 
Notifications
Clear all

Weather compensation and air source heat pumps

143 Posts
23 Users
50 Likes
16.3 K Views
Morgan
(@morgan)
Noble Member Member
3620 kWhs
Joined: 3 years ago
Posts: 504
 

Posted by: @abernyte

I am afraid that I have never peered too deeply into the settings to find exactly how the curve is configured. The installer spent some time on this part of the commissioning and  acknowledging that the house is a leaky and exposed timber frame he wanted to match the "normal" heat loss  with the input as low as possible and I do not seem to get much cycling at all with long uninterrupted runs unless defrost is called for.  It was further tweaked by a couple of local (Perth) Mitsubishi service agents when it got it's first service from them at year three. They squeezed out every last drop of efficiency and got the normal flow temps down even further so it rarely goes over 35C.  Big radiators and a big heatpump and a heavy dose of glycol to boot.  They only do heat pump servicing and repairs with Mitsubishi and Daikin, no installation work, and are worth every penny!

@Abernyte

Where are you based? I would love to find a company such as you have found to service and tweak my installation in the E Midlands area.

Currently, my service is carried out by the installer who isn't very close to my location, isn't exactly cheap and charges a hefty mileage fee on top. I'm sure my set up can be improved.

 

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
ReplyQuote
Abernyte
(@abernyte)
Reputable Member Member
2241 kWhs
Joined: 1 year ago
Posts: 114
 

Hi @Morgan,

I am a bit away from you in the hills of eastern Perthshire. I reluctantly switched the servicing away from the very knowledgeable installer when he became seriously ill and took out the Mitsubishi contract to avoid potentially sitting looking at a dead heat pump mid-winter wondering who to trust to repair it. It has worked out well, if a touch pricey, for complete piece of mind.


   
ReplyQuote
Morgan
(@morgan)
Noble Member Member
3620 kWhs
Joined: 3 years ago
Posts: 504
 

@abernyte 

Understandable.

If anybody can recommend in the Derby, E Midlands area I'd be obliged.

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
ReplyQuote



(@mike-h)
Reputable Member Member
973 kWhs
Joined: 2 years ago
Posts: 107
 

Posted by: @morgan

@abernyte 

Understandable.

If anybody can recommend in the Derby, E Midlands area I'd be obliged.

Hi, you might try Daniel at

https://www.reliablerenewables.org

He recently serviced a friend’s Mitsubishi ASHP in Dronfield and seemed good. He ‘charges £170 plus VAT for the service and this will be a one off payment for the year and covers unlimited call out and maintenance required if the system stops working.
You wouldn’t have to deal with any call centre and I can be out next day to you.’

He used to work for my installer, but left as he didn’t agree with their customer care, which was a recommendation in itself as I couldn’t agree with him more!

 


   
Kev M and Morgan reacted
ReplyQuote
Morgan
(@morgan)
Noble Member Member
3620 kWhs
Joined: 3 years ago
Posts: 504
 

@mike-h 

Thank you very much.  Very much appreciated.

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
ReplyQuote
(@sarah)
Estimable Member Member
410 kWhs
Joined: 1 year ago
Posts: 79
 

@kev-m


   
ReplyQuote
(@sarah)
Estimable Member Member
410 kWhs
Joined: 1 year ago
Posts: 79
 

Hi - I found this great forum and changed some of my setting in the early part of the year.  I set the compensation curve (through the engineer mode on my Mitsubishi Ecodan controller) to 40 and -3 - however when I look at the compensation curve NOT via the engineer mode - it says 40 and -30 - I cannot seem to change this or do I just ignore?  Also Having my system set at 40 doesn't seem to get one of my rooms with UFH up to temp and although the temp in that room is set to 18 it NEVER gets to that - this is since I changed to compensation mode back in March - I've only really noticed it in the recent code weather - last week - the temp never got above 15 - any ideas?  Many thanks.


   
ReplyQuote
(@derek-m)
Illustrious Member Moderator
12828 kWhs
Veteran Expert
Joined: 3 years ago
Posts: 4018
 

The problem may be due to the flow being too low to the UFH loops in that particular room. Can you provide a photo of the UFH manifold?

 


   
Mars reacted
ReplyQuote
 Gary
(@gary)
Estimable Member Member
663 kWhs
Joined: 1 year ago
Posts: 85
 

@sarah can you also post a picture of your WC curve.

When the heat pump is running under the engineer mode go to running information and input code 540 this will tell you the flow rate of the heat pump in litres per min.

 

If you have the Mel cloud app pictures of the hourly flow and return temp would also be useful

As Derek has eluded to it will either be the heat pump not getting the water to temp or the flow in the UFH being too low or not on for long enough is it running 24/7 or do you set back at night?  Do you know how deep the UFH is set in the concrete?  Is the UFH zoned and controlled by different thermostats in each room?


   
ReplyQuote



(@sarah)
Estimable Member Member
410 kWhs
Joined: 1 year ago
Posts: 79
 

@gary Hi the temp is controlled by three boxes in each room (it's only about 80sq metres in total) - they go down over

IMG 8195
IMG 8194
IMG 8192
IMG 8193
IMG 8191

 night - only to about 16


   
ReplyQuote
(@sarah)
Estimable Member Member
410 kWhs
Joined: 1 year ago
Posts: 79
 

@gary picture of flow rate

IMG 8196

   
ReplyQuote
(@sarah)
Estimable Member Member
410 kWhs
Joined: 1 year ago
Posts: 79
 

I have also (last night) changed the comp curve to 45 (from 40) - it's not too warm outside today - so I will see if that makes a difference.  I've never been able to get this right in the 8 years I've had it - it either uses so much electricity when running that we are at the stage where we have to decide if we can afford to run it or when I make changes it doesn't heat up the area.  I really want to like the ASHP but I never have.


   
ReplyQuote
Page 10 / 12



Share:
x  Powerful Protection for WordPress, from Shield Security
This Site Is Protected By
Shield Security