Forums

Search with Wattson
Forums
Renewable Heating
Air Source Heat Pum...
My Mitsubishi ASHP ...
 
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!

My Mitsubishi ASHP has used 1078kWh from 25 November to 31 December – Help please

 
Page 8 / 11
Air Source Heat Pumps (ASHPs)
Last Post by Sarah 3 years ago
122 Posts
8 Users
17 Reactions
25.7 K Views
RSS
 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 9:38 pm  

@derek-m I'm not sure how to bleed out the air - is there normally a valve somewhere?



   
ReplyQuote
 Derek M
(@derek-m)
Illustrious Member Member
Joined: 5 years ago
Posts: 4425
09/03/2023 9:49 pm  

Posted by: @sarah
↑

@derek-m I'm not sure how to bleed out the air - is there normally a valve somewhere?

There will be an air release valve somewhere, but I'm not certain where it will be located, normally in the highest section. I suggest that you Google 'Air Release Valve' and look for something similar. If you provide a close up photo of your water pump, I will see if I can locate any details.

 



   
ReplyQuote
 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:04 pm  

@derek-m

5A2A58F0 9A9A 4A19 BFDE 5BE3A4187CDF
6582AE86 B0B5 4666 9568 6FA3A64B4B69

 Not sure if these help - yes been looking at videos !



   
ReplyQuote



 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:12 pm  
EC74D741 B891 4B4D AEAC 16B8FF2550C4

Maybe this ?



   
ReplyQuote
 Derek M
(@derek-m)
Illustrious Member Member
Joined: 5 years ago
Posts: 4425
09/03/2023 10:14 pm  

@sarah 

It would appear that you have 3 water pumps and what could possibly be a plate heat exchanger. I would need to be able to read the model number from the nameplate on the pumps or you could provide it.

Do any of the pumps have more than one cable connected?



   
ReplyQuote
 Derek M
(@derek-m)
Illustrious Member Member
Joined: 5 years ago
Posts: 4425
09/03/2023 10:19 pm  

Posted by: @sarah
↑
EC74D741 B891 4B4D AEAC 16B8FF2550C4

Maybe this ?

Does it have a nameplate?

 



   
ReplyQuote



 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:27 pm  

@derek-m think pumps are grundfos ups2



   
ReplyQuote
 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:31 pm  

@derek-m not that I can see



   
ReplyQuote
 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:35 pm  

@derek-m better pictures

9D2C6888 769D 41E1 A2C2 597D02D1A7E7
83351BBB 1FF4 4ADB 8825 E7FAE86831F7
0CE34296 58B7 478D 8832 55C0C0183F3D


   
ReplyQuote



 Sarah
(@sarah)
Trusted Member Member
Joined: 3 years ago
Posts: 79
Topic starter 09/03/2023 10:51 pm  

OK looking at the picture of the three pumps - the one on the right has a fixed setting of 3, whereas the other two only light up on demand - although I've only seen the middle pump light up.  I've just looked at the flow rate (at 21:50) and it is zero - so tomorrow morning - I will go down and sit in the machine room for bit and see if both the middle pump and the one on the left both "switch" on and then will see what the flow rate on the control panel is.  Thanks once again.



   
ReplyQuote
 HarriUp
(@harriup)
Estimable Member Member
Joined: 4 years ago
Posts: 108
09/03/2023 11:05 pm  

Given that your living room wasn't getting up to target with a fixed flow of 40° then it is not surprising that changing it to a lower variable temp flow means it is struggling in a cold patch! The flow gauge at 28° seems like it is not as hot as the curve suggests it should be for the current conditions. Without Melcloud to easily monitor flow temps for the previous 24hrs it is down to you to read the controller panel to see what it is registering at the thermistors positioned one the hot water tank pipework – I think if you switch back to a fixed flow temp then you know what the unit is being asked to produce and you can see whether it is actually producing something like that. This comes with the caveat that actual flow temps do vary quite a bit as the system is working.

Looking at your spreadsheet I see you had a U1 alert, which I presume was down to the low water pressure, which should now be resolved. Generally your energy usage is reasonable given the area being heated (2/3 of my totals for Jan and Feb for example) but the amount of heat the unit calculates is being produced is not good, either in the raw figures or, clearly, in the rooms themselves. When the heating is running for several hours at 40° (lets assume it is) but a room is not getting warmer then something is awry.

Having a setback that has the effect of switching off heating going in for several hours does help keep electricity costs down especially with your solar production during the day but only if you can get enough heat out to raise the temperatures back up. The temps you have noted at 9am seem ok, not far off required temp unless it has been a colder night, and you say the bedroom and bathroom are getting up to temp but the living room isn't. A record of temps during the day would also help to highlight how fast the spaces are getting heat. Tedious I know, but it might help narrow down the source of the issue.

Although I have no experience of UFH systems I merely suspect that it is something possibly quite technical that needs investigation since you have had under-performance since installation.

.... I've just caught up with the latest few posts and I would say there is definitely an issue with some pipework somewhere. I know your Ecodan system is an earlier installation than mine but I don't think the basic design is any different. My pump speed set at 5 gives a flow rate of 26l/m, even 1 gives me 15l/m. The required flow rates are 11-24l/m so yours is at the bottom of the range. The question is why is it low – a faulty pump? or a restriction in the circulation somewhere?

What is the temperature like in your plant room? There is no insulation on that copper, including round the flow and return temperature thermistors clipped to the pipes! Not ideal.


Mitsubishi EcoDan 8.5 kW ASHP - radiators on a single loop
210l Mitsubishi solar tank
Solar thermal
3.94kW of PV


   
ReplyQuote
 Derek M
(@derek-m)
Illustrious Member Member
Joined: 5 years ago
Posts: 4425
10/03/2023 12:26 am  

Posted by: @sarah
↑

OK looking at the picture of the three pumps - the one on the right has a fixed setting of 3, whereas the other two only light up on demand - although I've only seen the middle pump light up.  I've just looked at the flow rate (at 21:50) and it is zero - so tomorrow morning - I will go down and sit in the machine room for bit and see if both the middle pump and the one on the left both "switch" on and then will see what the flow rate on the control panel is.  Thanks once again.

I would suggest that you check where each pump is connected and feeding. I suspect that the right-hand one may be for your DHW, since it appears to be connected to a plate heat exchanger. This pump should only run when the DHW is being heated.

The other two pumps could be feeding each of the UFH manifolds, but it is difficult to tell from photo's. See if you can sketch where the pipes are connected to the equipment.

If your rooms are not up to temperature then the central heating pumps should be running, along with the heat pump. If these pumps are not running then increase your thermostats by 1C.

 



   
ReplyQuote



Page 8 / 11
Forum Jump:
  Previous Topic
Next Topic  



Share:

Join Us!

Worth Watching

Latest Posts

Members Online

Click to access the login or register cheese
x Powerful Protection for WordPress, from Shield Security PRO
This Site Is Protected By
Shield Security PRO →