ᐅ Which Heat Pump? Ventilation System / Air-to-Water Heat Pump

Created on: 17 Aug 2016 20:27
M
Maderl
Hello,
My husband and I are currently trying to decide which heating system to install in our planned house.
I insist on having a ventilation system and a wood-burning stove in the living room. So the heating should be compatible with these.
Our chosen construction company has now offered us three heat pumps:

Air-to-water heat pump: Nibe F2040-8 with Nibe VVM320
Exhaust air heat pump: Nibe F750 P with supply air module SAM 40
Ground source heat pump: Nibe 1245-6 with deep drilling

My husband currently prefers the exhaust air heat pump because he thinks it works like the air-to-water heat pump but makes better use of the warm air from running computers... Everywhere I read, though, it says: "Avoid exhaust air heat pumps unless you are building a passive house."
Does the supply air module actually make it function somewhat like an air-to-water heat pump, but with better use of the warm indoor air?

The house is planned as a two-story timber frame construction with KfW 55 standard. To be honest, I am completely overwhelmed by this complicated heating topic. The more information I get, the more complex it seems.
L
Legurit
17 Aug 2016 22:59
If the budget allows, I would choose a brine-to-water heat pump with controlled mechanical ventilation; alternatively, an air-to-water heat pump with controlled mechanical ventilation.
M
Maderl
17 Aug 2016 23:05
Yes – but why? I somehow have to convince my husband... Men can be so stubborn *sigh*
L
Legurit
17 Aug 2016 23:13
Because the ALWP is expensive and not more efficient than an air-to-water heat pump combined with controlled mechanical ventilation with heat recovery.
The ground-source heat pump combined with controlled mechanical ventilation with heat recovery has the highest initial investment costs but the lowest operating costs.
G
Goldi09111
17 Aug 2016 23:18
Silly question, but what are the disadvantages of gas?
M
Maderl
17 Aug 2016 23:24
1. No piping and 2. my personal rejection of gas. It’s not rational, but I simply don’t like it.
G
Grym
18 Aug 2016 01:02
I calculated the annual costs based on the local rates from our utility provider, which of course vary everywhere, and I arrived at roughly 820 EUR for gas, 650 EUR for a mid-range air-to-water heat pump, and 550 EUR for a good ground-source (geothermal) water-to-water heat pump. With gas, you inevitably get some solar heating included, but you also have additional costs for electricity and chimney maintenance. For heat pumps, electricity costs are included in the annual performance factor. All calculations are based on my data (my local prices here; annual performance factor figures from the German Heat Pump Association).

Unfortunately, a ground-source heat pump hardly pays off compared to an air-to-water heat pump, especially if you have good insulation and, for example, like us, meet KfW55 energy efficiency standards. The drilling would cost us about 9,000 EUR, and the heat pumps themselves don’t differ much in price. Even with subsidies, that’s 4,500 EUR more, which would take 45 years to compensate for. Unfortunately. I would have liked a ground-source heat pump, but an air-to-water heat pump is the logical choice.

I wouldn’t recommend an exhaust air heat pump, that’s correct. The Nibe solution with an exhaust air heat pump is also not a ventilation system. Take a look at the system. The fresh air does *NOT* flow “preheated” through holes into the house. I had those poor solutions on my radar a year ago as well. No, a ventilation system is a good investment, as you say, and heating is a separate system. With a good insulation standard, an air-to-water heat pump is actually the best option. A ground-source heat pump if you value having no equipment mounted on the side of your house and want the best eco-friendly conscience.