@derek-m Thanks Derek, I've had a look and while I can't see the zones I have seen different charts but not sure what the symbols mean...

 I clicked on F4 here and got this screen below..

 This above was the screen on F2

 above is the screen from F3

below is the screen from F4

I've also attached this screen below from another page - not sure if this helps?

Hi @marknhudson 

It would appear that your weather compensation is set to a water flow temperature of 45C at an outside air temperature of -3C, with the other end of the slope set at 30C at 15C.

Adjust the slope using the 'F' keys to 45C at -10C and 25C at 18C. Allow the system 12 hours or more to stabilise and see what the various thermostats are reading and report back.

Hi @marknhudson 

To be able to provide the best possible help and advice, could you provide the following information.

Heat loss calculations for your home.

The total output rating of all the heat emitters.

If your system has a buffer tank and external water pumps installed.

If a booster heater or backup heater has been installed.

Your energy usage in kWh rather than £'s.

If you have any other energy hungry equipment besides your heat pump.

The level of insulation and any large areas of glass.

Posted by: @marknhudson

I'm new to this forum (and any online forum for that matter). I'm at my wits end with an ASHP that's costing over £450 pcm in a new build home (Oct & Nov). December is on course for £550 for the month according to the smart meter. Despite assurances from Mitsubishi and independent experts that I'm set up correctly I can't believe that's true. 

I have a Mitsubishi Ecodan 14kw ASHP

Underfloor heating downstairs

Rads on 2nd and 3rd floor in a 5 bed house approx 3000 square foot home.

House build in late 2018.

Please could you point me in the right direction for some advice?

Thank you

Hi Mark,

I'm sure Derek will be able to help you. 

Is the cost you quote definitely just for the heat pump? In your last picture, the top number is 895 and if it's like mine (I have the same ASHP), then that is the electrical energy consumed for the month to date (i.e. what you pay for) in kWh, for heating and HW.  895 kWh isn't that much for most of December and definitely won't cost you £500 or so.  Mine currently says 763.  The other number, 2049, is the energy delivered so far and dividing it by the first number gives to the COP.  At about 2.3 it isn't great but it's not disastrous either.

If you're on Ofgem cap, then £500/month is nearly 80kWh/day.  That would be huge amount for an ASHP to be using in such a mild December in a modern house.  

Just to compare, I have the same ASHP as you in a smaller (1700 sq ft) but almost certainly less well insulated (1990 bungalow) house. My heating will cost about £160 in December. That's to heat the whole house to 21C most of the time, using all radiators (no ufh).  

Good luck with the changes and keep us updated.

@marknhudson, welcome to the forums. Who’s your energy provider and what’s your tariff?

@editor Thanks Mars, our energy provider is now EON after Igloo went under and our tariff is 19.25p per kw.

@kev-m Thanks Kev. We also have a large hot tub which understandably isn't cheap to run but I've factored in about £20 per week to heat that on average over the year. We had some extra meters fitted so I could monitor the energy consumption of the hot tub, ASHP and then I also take a meter reading from the box outside. I've attached a screen grab of the spreadsheet I had been using and will start using again (geeky I know). You will see that the last time I monitored it was Feb / March time so the weather was slightly better than Nov / Dec. I've also updated the figures with the current rate per KW to give me a comparison. 

For the period I monitored the average daily consumption / costs were:

Air Source 28kw / £5.39

Hot Tub 17.88kw / £3.44

Remaining 26kw / £5.00

@derek-m Thanks Derek, I'll try those settings

@derek-m Hi Derek, I'll find out about the first few you asked about as I'm not sure.

Energy consumption from start of October to start of December averaged at 70kw per day but I fear this will be higher for December.

We have a hot tub which averages at around 17kw per day.

We have some bi-fold doors at the rear which are 6.6m in length plus a lantern roof in the dining room

Posted by: @marknhudson

@kev-m Thanks Kev. We also have a large hot tub which understandably isn't cheap to run but I've factored in about £20 per week to heat that on average over the year. We had some extra meters fitted so I could monitor the energy consumption of the hot tub, ASHP and then I also take a meter reading from the box outside. I've attached a screen grab of the spreadsheet I had been using and will start using again (geeky I know). You will see that the last time I monitored it was Feb / March time so the weather was slightly better than Nov / Dec. I've also updated the figures with the current rate per KW to give me a comparison. 

For the period I monitored the average daily consumption / costs were:

Air Source 28kw / £5.39

Hot Tub 17.88kw / £3.44

Remaining 26kw / £5.00

 

 

Based on these figures in your spreadsheet you can extrapolate your estimated cost over the year. The figure I get is £1400. Which given the size of your house looks about right.