Hitachi Yutaki S80 vs Daikin Altherma?

[ashthekid]

I've had two quotes from different heating companies and they have recommended these two:

Hitachi Yutaki S80 16kW  - high temp with rads upstairs

COP 4.57

Energy class A++

or

Daikin Altherma - low temp with UFH upstairs

COP 4.20 (I think)

 

What are people's thoughts on these two and which one is better/newer/more efficient?

[ashthekid]

Any thoughts on this?

[PeterW]

Neither are monoblock so you have the internal units to contend with. I think the Hitachi has secondary heating in the internal unit as it claims 80°C but only has R-134a refrigerant which maxes out before then. 

[ReedRichards]

It seems to me that if you mix radiators and underfloor heating then whilst the radiators are on you need the leaving water temperature from your heat pump to be high enough to suit the radiators so you don't get the efficiency/CoP benefit that you would from a house that uses just UFHs and so can use a lower leaving water temperature.  Possibly if you have the UFH on all of the time and the radiators on some of the time then the heat pump can be programmed to reduce its leaving water temperature when there is no demand from the radiator zone.  But I'm not sure if the control for my heat pumps is sophisticated enough to do that. 

[TW9]

Check the COP on the Hitachi if you're asking it to produce hot water. I think the COP over 4 is only if it's running at 30/35 degrees. When you get to 55 degrees the COP is about 2.1.

[J1mbo]

I would personally look for a product using R32 or R290.

[ashthekid]

Daikin have a fairly new 16kW Altherma 3 split system that uses the new R32 but I cannot find it anywhere online where it states it can be used over distances of 40m which is what I need.

 

Any help on finding that?