KfW 70 Ventilation / Exhaust System

Unfortunately, full modulation is an unknown term there An outdated "On/OFF" technique.

v.g.

better to first ask which Tecalor is installed before simply criticizing

Tecalor THZ 303 Integral
...Supply/exhaust air volume flow 80-230 m3/h...

"...Electronic outdoor temperature-controlled regulation for heating circuit. Electronic stepless adjustment of the fans. Intelligent control with program preselection for fans, heating, hot water and absence. Integrated control unit also possible as remote control unit. Expansion vessel 7.5 l/0.75 bar, circulation pump....

I believe linking is not allowed.

Best regards

...better to first ask which Tecalor is installed before simply criticizing

The Tecalor is identical to SE. Full modulation means that both evaporator and compressor are adjusted to the required heating capacity. Neither SE nor Tecalor currently have a solution for this!

An on/off device:

A fully modulating air heat pump:

Hopefully you have a very well-insulated building, otherwise the later consumption costs for heating and hot water could overwhelm you.
What is the calculated heating load according to DIN 12831?
These Combi- (Compromise) solutions are very often sold by general contractors/subcontractors because they are cheap

f.y.

The Tecalor is identical in construction to SE. Full modulation means that the evaporator and compressor are adjusted to the required heating capacity. Neither SE nor Tecalor currently have a solution for this!

An on/off device:

A fully modulating air heat pump:

Hopefully you have a very well-insulated building, otherwise the later consumption costs for heating and hot water could overwhelm you.
What is the calculated heating load according to DIN 12831?
These Combi- (Compromise) solutions are very often sold by general contractors/contractors because they are cheap

v.g.

Thanks for the clarification regarding the air-water heat pump and full modulation,

but I believe that was off topic.
The topic of the thread was the ventilation system, and that someone above wanted to sell slots in the window as a ventilation system.

In our case, the ventilation system is integrated into the Tecalor heating system.
Furthermore, our house is insulated with 17 cm thermal insulation at the top and 12 cm in the basement.

Best regards
Ralf

Dear community,

in our building description there is a controlled ventilation / exhaust system for our future KfW70 house.

With windows that have ventilation slots, I cannot detect any controllability. Moreover, if the word SYSTEM is mentioned there, I assume it is a technical device and not a "leaky window" (exaggeratedly speaking).

The best part is that these slots are only cut after the door blower test.
1. Question: will he achieve KfW70 with this?
2. Question: is he allowed to cut the slots only after the door blower test?
Thank you very much for your feedback

Regards, Michael

In my opinion, the building must be tested as it will be delivered. Therefore, the cutouts should already be present when the blower door test takes place, exactly as you will then receive it.

You could do the same test on a cardboard house and then make some holes afterward => completely distorts the result.

After all, the house must also meet the required airtightness value after handover. If it is allowed with the holes, it must be tested with them (and that should not be a problem). And if it worsens the values (which is to be expected), this must also be taken into account.

Best regards, Thomas

Hi, we also received an offer from our developer for the central controlled residential ventilation with the Zehnder ComfortAir 350. However, the whole thing is supposed to cost just under €12,000. Could you please tell me if that price is similar to yours or rather high? I would be very grateful for a bit of certainty. Best regards, Patrick