Cost-benefit comparison of controlled residential ventilation with/without EWT

Hello,

we are still in the planning phase of our property. Now we are asking ourselves about a geothermal heat exchanger for the [Kontrollierte-Wohnraumlüftung]? The type has now been determined. It will be a Zehnder ComfoAIR 350 with enthalpy. The heating engineer also mentioned that a geothermal heat exchanger for the [Kontrollierte-Wohnraumlüftung] would be cost-effective, as then the heating elements for the frost period would be unnecessary.

Now I am wondering when something like this pays off? Just for the geothermal heat exchanger I am easily looking at 1,600 plus VAT, without installing it. The ventilation system was already a concession from my partner, but another ~2,000€ on top for a geothermal heat exchanger?

What are the experiences like? When and how often does the heating element then turn on and what extra costs come up per year, assuming the region is HRO?

I would be very happy if some people could share their experiences who have already dealt with this...

Best regards
mirage

Hello,

... with enthalpy.

I would have spared myself that

...The heating engineer also said that a geothermal exchanger would be advantageous for the controlled residential ventilation, as then the heating elements for the frost period would be unnecessary.

Does he just say that and include this as a complaint-worthy point in the contract?

... What are the experiences like? When and how often does the heating element then switch on and what does it cost extra per year, assuming the HRO region?

Ask your TGA planner.

Regards

Hi,

yeah, alright. Are there any experiences with a controlled residential ventilation system, regarding how much power the unit consumes on average in kW/year without a ground heat exchanger? That would give a rough overview and estimate, as the entire heating period is represented there, including frost days with a heating element for air warming.

Best regards
mirage

The geothermal heat exchanger is worthwhile with the plate heat exchanger at outdoor temperatures below -2°C! With the rotary heat exchanger, never! I am not exactly sure how it is with the enthalpy exchanger. I would ask Zehnder about frost protection for that, as it exchanges moisture similarly to the rotary heat exchanger, and it is therefore possible that the geothermal heat exchanger is no longer worthwhile.

However, the geothermal heat exchanger is also worthwhile because it also pre-cools in summer!

How much you save depends on your air exchange!