ᐅ Which Heating System Is Suitable for a Multi-Family House If a Heat Pump Is Not Eligible for Incentives?
Created on: 24 Apr 2023 17:18
D
deri254
Hello,
since early 2020, I have been building a multi-family house (4 apartments with a total living area of 435 sqm (4,680 sq ft) over 2 floors, underfloor heating) in Bavaria. The energy efficiency standard is just about KfW55. At that time, I did not apply for any subsidies because I have done everything myself except for the roof structure, so I only purchased the materials. In 2020, the only option for me was to install an oil heating system. However, given the developments in recent months, the only sensible option now would be a heat pump. Since I did not apply for any funding before the start of construction in 2020, as far as I know, it is no longer possible to get subsidies for the much more expensive heat pump. Or is there still a possibility in my case to receive funding for the heat pump? Otherwise, my only option would be to install an oil or gas heating system (the latter with a biogenic liquid gas tank in the garden) before the end of the year.
Another detail: 10 meters (33 feet) away on another parcel, there is my farmhouse, completely renovated and somewhat insulated between 2014 and 2017 (approx. 118 sqm (1,270 sq ft) living area over 3 floors, with radiators), but still using a 25-year-old oil heating system. Last year, as a precaution during sewer works, I already installed a thermal pipeline between the two houses up to the boiler room. Here, funding for replacing the heating system would be possible. Would it therefore be conceivable to easily get subsidies if both houses were run with a single heating solution? According to the heating installer, a heat pump for the renovated house would not be without challenges.
Thank you.
since early 2020, I have been building a multi-family house (4 apartments with a total living area of 435 sqm (4,680 sq ft) over 2 floors, underfloor heating) in Bavaria. The energy efficiency standard is just about KfW55. At that time, I did not apply for any subsidies because I have done everything myself except for the roof structure, so I only purchased the materials. In 2020, the only option for me was to install an oil heating system. However, given the developments in recent months, the only sensible option now would be a heat pump. Since I did not apply for any funding before the start of construction in 2020, as far as I know, it is no longer possible to get subsidies for the much more expensive heat pump. Or is there still a possibility in my case to receive funding for the heat pump? Otherwise, my only option would be to install an oil or gas heating system (the latter with a biogenic liquid gas tank in the garden) before the end of the year.
Another detail: 10 meters (33 feet) away on another parcel, there is my farmhouse, completely renovated and somewhat insulated between 2014 and 2017 (approx. 118 sqm (1,270 sq ft) living area over 3 floors, with radiators), but still using a 25-year-old oil heating system. Last year, as a precaution during sewer works, I already installed a thermal pipeline between the two houses up to the boiler room. Here, funding for replacing the heating system would be possible. Would it therefore be conceivable to easily get subsidies if both houses were run with a single heating solution? According to the heating installer, a heat pump for the renovated house would not be without challenges.
Thank you.
deri254 schrieb:
But what I’m especially interested in is which manufacturer/model of heat pump could be confidently chosen for a multi-family house based on price/performance/guarantee without subsidies (without fear or doubts compared to well-known brands that it might fail to perform)What output does your calculation indicate? As for manufacturers outside the major players in Germany, options would be, for example, the Panasonic Aquarea J in 12kW (12,000 BTU) WH-MXC12J9E8 or 16kW (16,000 BTU) WH-MXC12J9E8,
or LG’s Therma V Monobloc S, which is also available in similar performance levels.
What I don’t understand is this: they all cost about half as much compared to the well-known manufacturers and would even be eligible for subsidies, although not for me. If, as mentioned above, I don’t need the expensive chimney in my new build, the heating system would actually be cheaper than an oil or gas heating system. So why do people still install non-subsidized new oil heating systems like crazy (even during renovations, you usually have to retrofit a plastic pipe in the chimney)? Granted, with oil or gas heating, you can of course save on buffer tanks.
Where’s the catch with these cheaper heat pumps? Are the heat pumps mentioned above really safe to install without concerns?
Where’s the catch with these cheaper heat pumps? Are the heat pumps mentioned above really safe to install without concerns?
deri254 schrieb:
Where’s the catch with these cheaper heat pumps? Are the ones mentioned above really safe to install without concerns?Panasonic is one of the largest heat pump manufacturers worldwide and definitely not a small-time developer. They practically invented the heat pump. Modulating compressors, phase angle control, pulse width modulation – none of this comes from Germany, but from East Asia. Whether it was Panasonic, Mitsubishi, or LG (Korea), I don’t know, but they all know what they’re doing. Why are they so “affordable”? Because heat pumps aren’t rocket science and are actually easier to build than gas or oil condensing boilers. Almost the entire world heats and cools with heat pumps, and large tech companies produce many of them. The materials aren’t particularly complex; the only sensitive parts are the compressor and the control software, which ensures maximum efficiency.
Generally, monoblock units are cheaper than the split systems commonly installed here. The difference is that in a split system, the evaporator and compressor are outside, connected by refrigerant lines to the indoor unit, which contains the condenser/heat exchanger and auxiliary components (3-way valve for hot water, expansion vessel, possibly a dirt separator).
In a monoblock, the pump, heat exchanger, and sometimes the expansion vessel are also installed in the outdoor unit. This means no separate indoor unit is needed, just a control panel, piping, and a valve for hot water production. Also, you don’t handle refrigerant inside and therefore don’t need a special certification for installation or commissioning.
In Germany, it’s largely a matter of market access: installers have worked with Viessmann, Buderus/Bosch, Vaillant, Weishaupt, and maybe Wolff for 70 years or more. When they need something, they ask those suppliers. Panasonic (and other Asian/American competitors) simply aren’t as well established here yet – see Carrier’s entry through Viessmann.
Appearance also matters here, and it’s fair to say that a Bosch turbine in the front yard looks more appealing than an Asian heat pump with a backyard air conditioning unit aesthetic. But this is changing. The new Panasonic K/L series is quieter than Hydrosplit systems (refrigerant in the outdoor unit with heat exchanger, only water pipes inside, and an indoor unit with pump, filter, expansion vessel, and 3-way valve for almost “plug and play”), uses propane as refrigerant, and its design matches German market standards – it’s a bit more expensive than previous models but still significantly cheaper than some competitors.
Hello,
Since I still don’t have heating installed but now need to make a final decision on whether to install a gas heating system with a biogenic liquefied gas tank in the garden or to go for a heat pump instead, I wanted to ask for your opinions. I have now received a quote for a heat pump at almost the same price as the gas heating system because the latter still uses the old refrigerant R410A. The heat pump is a Bosch Compress CS7001iAW 17 ORE-T with 13kW. The heating installer said that I can expect a heating load of about 30W/m2 (3.0 W/ft2) for my building. Is it realistic that a 13kW heat pump will be sufficient for heating and domestic hot water (a 9kW electric backup heater is integrated)?
Here are my final details again:
Multi-family house with 4 residential units and approximately 15 people in total, total living area about 404 m2 (4,350 ft2), construction started in 2020, circulation line only on the ground floor due to a somewhat longer line to the kitchen, no ventilation system, underfloor heating on the ground and top floors, possibly only heat pump radiators in the attic. The design outdoor temperature for my location is -12.4°C (9.7°F).
U-value of floor slab: approx. 0.24
U-value of walls: approx. 0.23
U-value of roof: approx. 0.15–0.17
U-value of windows: approx. 0.90
U-value of roof windows: approx. 1.10
I am torn and have done a lot of research in the last few days but am still very uncertain. These heating loads are usually calculated assuming 20°C (68°F) room temperature. What happens if all occupants want a higher temperature? How would that affect the system?
I would be very grateful for your help as I need to decide in the next few days; otherwise, the heat pump option will no longer be feasible due to cost. Thank you.
Since I still don’t have heating installed but now need to make a final decision on whether to install a gas heating system with a biogenic liquefied gas tank in the garden or to go for a heat pump instead, I wanted to ask for your opinions. I have now received a quote for a heat pump at almost the same price as the gas heating system because the latter still uses the old refrigerant R410A. The heat pump is a Bosch Compress CS7001iAW 17 ORE-T with 13kW. The heating installer said that I can expect a heating load of about 30W/m2 (3.0 W/ft2) for my building. Is it realistic that a 13kW heat pump will be sufficient for heating and domestic hot water (a 9kW electric backup heater is integrated)?
Here are my final details again:
Multi-family house with 4 residential units and approximately 15 people in total, total living area about 404 m2 (4,350 ft2), construction started in 2020, circulation line only on the ground floor due to a somewhat longer line to the kitchen, no ventilation system, underfloor heating on the ground and top floors, possibly only heat pump radiators in the attic. The design outdoor temperature for my location is -12.4°C (9.7°F).
U-value of floor slab: approx. 0.24
U-value of walls: approx. 0.23
U-value of roof: approx. 0.15–0.17
U-value of windows: approx. 0.90
U-value of roof windows: approx. 1.10
I am torn and have done a lot of research in the last few days but am still very uncertain. These heating loads are usually calculated assuming 20°C (68°F) room temperature. What happens if all occupants want a higher temperature? How would that affect the system?
I would be very grateful for your help as I need to decide in the next few days; otherwise, the heat pump option will no longer be feasible due to cost. Thank you.
N
nordanney25 May 2025 23:29deri254 schrieb:
The heating engineer said that for my building, I can expect a heating load of about 30 W/m2 (3 W/ft2). Is it realistic that a 13 kW (17.4 hp) heat pump for heating and domestic hot water will be sufficient (with a 9 kW (12 hp) electric backup heater integrated)?I would guess that it is more than sufficient, especially with the support of the electric backup. Is the domestic hot water storage tank as planned?Similar topics