ᐅ Decision to install a heat pump

Good day,


I am currently planning a new heating system in North Rhine-Westphalia and have received several quotes.


At the moment, a gas heating system is in use, which will soon need to be replaced. The plan is to replace it with a heat pump.

The heat distribution system is underfloor heating covering 190 m² (2,045 sq ft) over two levels, and radiator heating for an outbuilding of about 40 m² (430 sq ft), which is usually only heated minimally (maintained between approximately 4 and 8°C (39°F to 46°F) during winter).

Additionally, a photovoltaic system of around 10 kWp, with the option to expand in the future, will be installed.

Currently, I have the following five estimates, which differ greatly both technically and in price.

(All prices include VAT.)

As a layperson, I naturally have little knowledge in this area and would appreciate advice on which offer is reasonable.

Furthermore, the various proposed heat pumps use different refrigerants: What should I pay attention to in this regard?

And more generally: What would you recommend?

Which brand is considered the best? Are there any that you would advise against?

Thank you very much in advance!

Best regards,

Lukas



1) Chofu with 16 kW (18,000 €)
(Installable this year)

CHOFU monoblock heat pump 16 kW

Refrigerant: R32

Switching valve
35 m (115 ft) piping
35 mm (1.4 inch) fittings
Including connection materials and installation


2) Bosch with 14.8 kW (26,400 €)
(Installable next January)

BOSCH split heat pump SAS 13-2 ASE, 14.8 kW, monovalent

Refrigerant: R410A

2x BOSCH remote controls/room controllers CR 10 H
BOSCH refrigerant lines SAS 3/8" and 5/8"
Wall mounting brackets for air/water heat pump
JUNKERS hot water switching valve 22-1 for heat pumps
Membrane expansion tank 25 l (6.6 gallons), silver, max. 3 bar
FLAMCO Flexcon suspension frame type MB 3
Logafix cap ball valve MK 3/4"
XStream vent-clean (DN20) K22
Pump group UK 1", without pump
Pump group MK 1", without pump
BOSCH mixing module MM 200 for 2 heating circuits
2x Grundfos circulation pumps Alpha1 25-60 180230V
2x Grundfos Alpha right-angle plugs, 4 m (13 ft) cable
Distributor bar for up to 3 heating circuits
BWT storage connection set 3/4" M KS 1267-34 M with 6 bar safety valve
Various pipes, fittings, and connectors
System filling according to ÖNORM
Work time: installation and connection of heat pump including accessories
Commissioning by factory service


3) IDM with 10 to 24 kW (45,000 €)
(Installable next March)

IDM AERO ALM heat pump 10-24 kW, modulating
Accessories AERO AL 10-24 (buffer tank, etc.)

Refrigerant: R290

3 x large-surface radiators
Various materials
Commissioning
Underfloor heating manifold
Small materials
Work time


4) IDM with 8 to 17 kW (30,000 €)
(Installable next December)

IDM AERO SLM heat pump 6-17 kW, with NAVIGATOR 2.0
Equipment variant HGL

Refrigerant: R410A

Commissioning
Room unit for one heating circuit to NAVIGATOR
EIB-KNX module
Air separator
Magnetic sludge separator
Refrigerant connection lines, length 5 m (16 ft)
Distributor for underfloor heating


5) Saunier Duval with 12 kW (25,000 €)
(Installable this October)

Saunier Duval heat pump with 12 kW

Refrigerant: R410A

3 x large-surface radiators
Various materials
Commissioning
Underfloor heating manifold
Work time

Hello! Without going into detail about each specific unit, I do notice that all the mentioned heat pumps are sized very large in terms of kW.

What is the heating load of the building? How much energy has been consumed per year so far?
What is the insulation standard?

I cannot provide specific insulation values, except that the walls are very thick, there is a thick layer of expanded polystyrene (EPS) insulation on the exterior, the intermediate ceiling is thicker than usual, and the windows are triple-glazed.

So far, the heating load calculations for the heat pump have always resulted in values between 12 and 17 kW.

Just for your information:

The current consumption is about 46,000 kWh of gas. However, this is also due to an old, inefficient, and poorly adjusted gas boiler. Everyone has told me that I should be able to manage with around 32,000 kWh.

The photovoltaic system currently does not have a battery storage.

The underfloor heating only requires a supply temperature of about 40 degrees Celsius (104°F). The hot water tank (possibly via a buffer tank) is also supposed to be heated by the heat pump.

There are no other heating sources at this time.

In a heat load calculation according to DIN12831, there is no range between 12 kW and 17 kW but a single specific value. If necessary, commission one yourself.

You cannot draw precise conclusions about performance from consumption. It works the same way with cars.