Help setting up 2 Daikin Altherma heat pumps

[dani146]

Hi all,
I build a house (290 square metters) and installed 2 Daikin indoor units EKHBX016A and 2 corresponding outdoor units Altherma ERHQ016.
My house is well insulated and was finished in November 2010.

The company that installed the 2 heat pumps set them up and leave.
All was ok untill cold weather came and with temp from -4 to -11 degree C. I have total power consumption of 120 - 150 kW in 24 hours.
This is way too much for me and now I try to find best recomended settings for the 2 heat pumps. (equilibrium point when the heat element to help the pumps and other settings).
At -7 to -11 degree C, the heat pumps (without electric heaters) can not get inside temp to 18 degree C (only up to 17.6).

I was told that, at my house dimensions and insulation, will have a total power drawn of 50 kW / 24 hours but it is 3 times that.

I really try to be "green" (not like Hulk :) ) and want to make this pumps work.

BR,
Daniel M.

PS I read through this forum but can not find solution yet.

[dani146]

extra information:
- heaters under floor and inside some walls (heating liquid temperature set at 35 oC)
- 3 levels in house with multiple zones but all controled at this moment by one thermostat
- I don't live in the house yet so no hot water needed
- I use and automatization controlled by a thermostat with an outside probe to start the second heat pump only at set temperature (at this moment at -8 oC)
- Today I modified the equilibrium temperature at [5.01] to -4 oC so under this temp will start the electric 9kW heater (untill today equilibrium point was at -13 oC)

[Mabe]

Standard 1x electric heater cames in for space heating at 0 degree when setpoint is not reached (backup 3kw) and one for domestic howater after 20 minutes (booster 3kw) try to play with these otherwise you now that in cold days 6kw electric is running.
My experiance is that a lot installers install the altherma but don' think about the hole system after a year customers are complaining for the cost of electricity, contact same one of Daikin maybe a commision by a now well person of altherma can solve lots of problems.

[sinewave]

One asumes dani that your 2 x 16kW units have no problems heating your house at 290 sq M despite the high elec consumption which will be down to the 2 x 3kW Imm heaters on Fullchat?

I take they are LT units not HT?


I do hope so being as my house is 350 sq M and only has 1 x 16kW HT unit heating it!

[brunstar]

Hi Dani,
How are your underfloor controls set up? are they on constantly or are they timed on and off?
How far away are your outdoor units from the indoor units?

[brunstar]

The other thing i might add is that usually in the UK systems are designed to room temperatures of 20 degrees at -3 and bedrooms to 18 at -3 so if these are the conditions the system have been sized to then the rooms will be a bit cooler when the outdoor ambient is colder..