Central supply and exhaust ventilation instead of a central exhaust system

Hello everyone,

after about 4 years we are going to build our house for the second time (wood stud frame same type, same builder), I do not want to go into the reasons any further. We are building the same house again (and not a different one) because we were satisfied all around. However, we will change small details. And I would like some input from you on one big matter:

In 2016 we built our house with a central exhaust system. The system was installed in the attic and extracted air from all wet rooms (2x bathroom, utility room, and kitchen). The climate in the house was perfect and largely without drafts. Only in the living room on cold days in the evenings there was a slight draft. I then closed the ventilation opening and eliminated the draft. The system was included in the total price.

We could now install a system with central supply and exhaust ventilation instead of the central exhaust system for an additional 4800 Eur. It is a Zehnder ComfoAir Q 350. The advantages I see:

-energy savings because of heat recovery (although small, we consumed about 50 Euros in gas per month for our 130 sqm with 3 people)
-more comfort, since no more drafts
-better appearance and sound insulation, since there are no ventilation openings to the outside anymore

My former site manager is currently on vacation, so I cannot ask him: Do you know if the system has humidity recovery as standard or is that an additional device? What additional cost should I expect?

Furthermore, I imagine that in 10-20 years a heat pump could be installed instead of the gas boiler, so the system should also be built in the utility room. Is that at all a feasible plan or is the ventilation system then constructed completely differently?

I would like to know your opinion on this. Especially because we have been completely satisfied with the exhaust system so far, I am unsure whether we should take the upgrade.

Regards,
Robin

Just buy an air-to-water heat pump with an annual performance factor greater than 4.5 and take advantage of the new BAFA subsidy. And also remember the KfW subsidy; it's worthwhile again nowadays.

At Zehnder, there is an enthalpy heat exchanger available for an additional charge, either installed right away (if you're lucky) or to be purchased later and inserted yourself. Alternatively, there is a CO2-based control system, but that's rather special.

So, now everyone is without exception curious about the reasons for the new building Was the color of the bathroom tiles chosen wrong during the first construction? :-p

We have the same system and it was the best decision in the entire construction. Always fresh air, quiet... simply top.

The ventilation is not directly connected to the heating, so you are free there. Even if you want gas now, you have to design the underfloor heating directly for a heat pump. Since the heating professionals are usually overwhelmed with this, the only advice is to get involved in the planning yourself. Room-by-room heat load calculation, set room temperatures, choose a low flow temperature, focus mainly on the bathroom, ...

What is certain now: for an additional 8990 (gas connection and solar thermal are omitted as well as Bafa) a Tecalor THZ 5.5 eco with 5.16 kW could be installed. Unfortunately, I don’t know whether the price includes an enthalpy heat exchanger or not. Otherwise, as described above, the house price includes a central exhaust system with gas boiler and solar thermal. Only the connection for the gas with 3451 is additionally incurred.

The Zehnder is no longer an issue for now (if I understood correctly, this also depends on the heating specialist). Should I pursue this further, is the Zehnder better? What is generally to be thought of the Tecalor? Unfortunately, I am completely unfamiliar with the different systems and also the technology, so it is difficult for me to form an opinion. I hope you can help me.

The Tecalor is actually a Stiebel. Just a combined unit. In my opinion, there is no enthalpy exchanger for them.