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High electricity use – 17kW Grant Aerona 3
Hi all.
Had a 17kw Grant Aerona 3 ASHP and Solar Panels fitted May '24 so it didn't get much use until around October '24. Radiators were all replaced/upgraded to K2 and K3 types.
Bills were low-ish in the summer as obviously no heating required, only hot water once per day.
Since the temperatures dropped the heating has been on constantly, two circuits, upstairs and downstairs, 2 stats set to 18 degrees. House temp is mostly ok but our electricity use has gone through the roof.
We're using 1800kWh per month for december, January and probably February, one day exeeded 110kWh in December!
We don't have any other form of energy so I realise that these figures include our electric hob and oven (used once daily for 1hr), microwave (used 3/4 times daily for short periods), washer and dryer 9 Used twice per week) and all other electrical items. Our house is an old, well insulated house, two occupants, both in all day working from home, running two computers 9 hours per day.
The house is a detached 5 bed stone with slate roof.
The installers aren't interested, they said everything is alright and it's working properly...
Does anyone exist who will come and assess/set up the system properly as I suspect it might improve if 'tuned'.
I've read heaps about changing settings but it's too confusing for me to entertain...
We're in N. Wales nr Ruthin.
Thanks.
I know the feeling I had exactly the same issue until I found someone capable of sorting the issues. I am in Cheshire and found a heat geek qualified guy locally Mark Rolfe from MSR renewables. He was a fraction of the price of anyone else who I spoke to and sorted mine in one full day and there was quite a bit of rectification work to do.i know Cheshire seems a long way off but I know Mark is planning on moving to north wales as he currently does a lot of work there.
tel 01270 874327
really nice guy very approachable understands all the issues and has trained with almost all major manufacturers. More importantly he won’t rip you off I genuinely wish I could find someone like him to do all my work on my major renovation sadly he only does heating etc !
Posted by: @jgtukpdI've read heaps about changing settings but it's too confusing for me to entertain...
Have you been reading the low-level advice which @cathoderay has been giving on the Topic about the Baxi ASHP?
That level of instruction on how to operate and maintain the system is a statutory requirement in the Building Regulations, Part-L (Conservation of Fuel and Power).
Posted by: @jgtukpdThe installers aren't interested
If they haven't complied with Part-L, then they should be "interested".
Did your Local Planning Authority send you a letter stating that the installation is compliant?
We'd need more detail from you to advise further.
1: What's a total floor area of the house?
2: Are you on a 3-phase electricity supply?
3: Do you have a copy of the original Energy Survey?
That document has the calculations which define:
- the size of heat pump required
- the size of emitter (radiator or underfloor heating) required for each room
Save energy... recycle electrons!
Thanks for the reply.
1. I'll investigate
2. Yes
3. Not sure if we have or where it might be - I was very ill at the time of the install and we had a lot of building work going on. Again, I'll have to investigate.
I have a poor relationship with the company who undertook the work. It's a long story but one of the sub contractors wandered off the site and into an unsafe barn and had a fall breaking his ankles very badly - He is trying to sue us for a huge amount of money so we've blamed his company and told him to take it up with their health and safety officer/insurers. It's in the hands of our solicitors.
The company have not played ball since then - difficult to contact, don't return calls etc. so I'd rather go another route if at all possible.
Posted by: @jgtukpdHi all.
Had a 17kw Grant Aerona 3 ASHP and Solar Panels fitted May '24 so it didn't get much use until around October '24. Radiators were all replaced/upgraded to K2 and K3 types.
Bills were low-ish in the summer as obviously no heating required, only hot water once per day.
Since the temperatures dropped the heating has been on constantly, two circuits, upstairs and downstairs, 2 stats set to 18 degrees. House temp is mostly ok but our electricity use has gone through the roof.
We're using 1800kWh per month for december, January and probably February, one day exeeded 110kWh in December!
We don't have any other form of energy so I realise that these figures include our electric hob and oven (used once daily for 1hr), microwave (used 3/4 times daily for short periods), washer and dryer 9 Used twice per week) and all other electrical items. Our house is an old, well insulated house, two occupants, both in all day working from home, running two computers 9 hours per day.
The house is a detached 5 bed stone with slate roof.
The installers aren't interested, they said everything is alright and it's working properly...
Does anyone exist who will come and assess/set up the system properly as I suspect it might improve if 'tuned'.
I've read heaps about changing settings but it's too confusing for me to entertain...
We're in N. Wales nr Ruthin.
Thanks.
It's understandable when looking at heat pumps, but getting information is just like pushing buttons on your TV remote.
If you want to take a look, let me know
Posted by: @uk_pete_2000Posted by: @jgtukpdHi all.
Had a 17kw Grant Aerona 3 ASHP and Solar Panels fitted May '24 so it didn't get much use until around October '24. Radiators were all replaced/upgraded to K2 and K3 types.
Bills were low-ish in the summer as obviously no heating required, only hot water once per day.
Since the temperatures dropped the heating has been on constantly, two circuits, upstairs and downstairs, 2 stats set to 18 degrees. House temp is mostly ok but our electricity use has gone through the roof.
We're using 1800kWh per month for december, January and probably February, one day exeeded 110kWh in December!
We don't have any other form of energy so I realise that these figures include our electric hob and oven (used once daily for 1hr), microwave (used 3/4 times daily for short periods), washer and dryer 9 Used twice per week) and all other electrical items. Our house is an old, well insulated house, two occupants, both in all day working from home, running two computers 9 hours per day.
The house is a detached 5 bed stone with slate roof.
The installers aren't interested, they said everything is alright and it's working properly...
Does anyone exist who will come and assess/set up the system properly as I suspect it might improve if 'tuned'.
I've read heaps about changing settings but it's too confusing for me to entertain...
We're in N. Wales nr Ruthin.
Thanks.
It's understandable when looking at heat pumps, but getting information is just like pushing buttons on your TV remote.
If you want to take a look, let me know
Any help would be gratefully received 👍
@jgtukpd sorry for delay I keep getting logged out
The following will one display your info, we are not changing any thing.....
Press the Return button
Till it bleeps. You will get 00 displayed.
Press the Tick button and release
You will see a number. This is the flow temp coming from HP
.....to get the next display press the up arrow
and press tick again.
Repeat this for 00 to 09 and let us know the results
End of txt
Thanks for confirming that you have a 3-phase supply to the property.
In that case it seems odd to me that the installer has specified the 17kW Grant Aerona³ ASHP.
From the manufacturer's own datasheet that would appear to be a single-phase unit.
That's a large heat-pump to operate from single-phase.
The quoted 3.76kW of power-input is specified for a flow-temperature of only 35°C.
I expect you are running at more than that.
There will have been a Low Carbon Technology application made to your Distribution Network Operator, which is SP Energy Networks.
Your installer should've provided you with that letter.
That's the point at which I would've expected a discussion between the installer and DNO, with a recommendation that the LCT connection was approved, subject to the heat pump being a 3-phase unit.
The overall current required from your local substation would be lower, and there would be reduced losses due to phase imbalance.
Those are major concerns for a DNO.
From your viewpoint, a 3-phase heat-pump is also more efficient.
The fan-motors and the compressor would be operating with 440v between phases.
Save energy... recycle electrons!
0= 31
1 = 60
2 = 52
3 = 5100
4 = 600
5 = -4
6 = 2
7 = 4400
8 = -3
9 = 41
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