ᐅ Controlled Residential Ventilation for Single-Family Homes – Planning and Design Using Helios Easyplan

Created on: 1 Mar 2018 09:28
A
Almo85
Hello everyone,

I am currently planning the design of the mechanical ventilation system with heat recovery. Initially, I used Helios Easyplan for the layout and will make some adjustments. Now, I am trying to find out whether the suggested supply and exhaust air outlets are positioned correctly. These were chosen based on other houses from acquaintances with a similar floor plan.

We are planning a room-air-independent fireplace and an exhaust hood. A differential pressure switch might be needed here, but this still has to be clarified with the chimney sweep.

Key details:
-Single-family house with 175 sqm (1883 sq ft) of living space spread over 2 full floors
-Concrete ceiling on the ground floor and upper floor
-Air-to-air heat pump
-Ventilation unit located in the attic
-The ventilation system will most likely be a Helios mechanical ventilation system EC 300 with 75mm (3 inch) ventilation duct

My questions for you are:

1.) I might only install the ventilation ducts in the concrete ceiling on the ground floor and on the concrete ceiling of the upper floor with appropriate ceiling outlets. Since I am unsure if my budget will be sufficient, I want to prepare everything this way (only ventilation pipes and ceiling outlets, close off ducts in the attic, plaster over ceiling outlets) and then decide whether to complete the system later by installing the distributors, unit, and the rest. I don’t want to lose the option of a mechanical ventilation system in the future and hope to prepare everything with a relatively low budget for now.
The siphon, electrical supply, and empty conduit will also be prepared.

2.) Preparation aside, the openings for supply and exhaust air must be made ready. What do you think about these locations? The bedrooms are supposed to have both supply and exhaust lines to be able to increase airflow to about 60 m³/h (35 cfm) while keeping noise levels low.

I am happy to receive all kinds of suggestions, criticism, and tips and will consider them in my planning.
Attached are the floor plan with supply and exhaust air, and the Helios design.

Thanks in advance.

Best regards,
Almo

Schematische Luftverteilung im Haus: Zuluft (rot) und Abluft (gelb) zu Zimmern, Bad und Küche


Querschnitt eines Hauses mit Treppen; rote Zuluft- und gelbe Abluftleitungen kennzeichnen Lüftung.


Grundriss eines Dachgeschosses mit Flur, Bad, Kind 1, Kind 2, Eltern, Ankleide; Zuluft/Abluft.


Grundriss eines Hauses: Wohn/Essbereich, Küche, Flur, Gästezimmer WC/Dusche, Abstellraum, Doppelgarage
Mycraft5 Mar 2018 09:39
Yes, the air then doesn’t have 22°C (72°F) but 20°C (68°F), which in my opinion is an exaggeration to call it cold. In addition, you’re not installing a high-velocity system (as is common in high-rise buildings); under normal operation, the air exits at about 1 m/s (3.3 ft/s).

Well, as I said, it’s up to you. The best thing is to visit someone who has a mechanical ventilation system with heat recovery and see it for yourself to get a feel for it.
andimann5 Mar 2018 16:26
Almo85 schrieb:
I just thought that with a relatively low supply air volume and air velocity (in normal continuous operation), the air would be pleasantly preheated by the heat recovery system.

It is, but if you sit directly in the airflow, you can definitely notice it. It’s not really uncomfortable, but it’s noticeable. A neighbor has a supply air vent right above the sofa, and at least she doesn’t like sitting there.

Best regards,

Andreas
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Almo85
5 Mar 2018 16:42
andimann schrieb:
It is, but when you’re sitting right in the airflow, you can definitely feel it. Not really uncomfortable, but noticeable. For my neighbors, the fresh air intake is located just above the sofa, and at least she doesn’t like to sit there.

Regards,

Andreas
Well, I think it depends heavily on how efficient the heat recovery is, and that in turn depends a lot on the ambient temperature where my system is located. Am I correct in understanding that?

Anyway, the system is installed up in the attic, which isn’t especially well insulated under the roof tiles. Do I need to insulate well around the system, maybe include the chimney within the insulation envelope, where the draft passes through, to create some preheating there?

Regards
Almo
Mycraft5 Mar 2018 16:55
You need to insulate enough to shift the dew point so that condensation does not form on or inside the pipes at the coldest local temperatures. Otherwise, structural damage may occur. Cases like this have already been discussed here in the forum.
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Almo85
5 Mar 2018 17:03
Mycraft schrieb:
You need to insulate at least enough to shift the dew point so that condensation does not occur on or inside the pipes at the coldest local temperatures. Otherwise, structural damage can occur. There have already been cases like this discussed in the forum.

Okay, condensate is dripping from the ventilation system into the wastewater pipe. Do you mean the condensate is spreading through all the air supply ducts in the house?
Mycraft5 Mar 2018 17:40
If the insulation is insufficient, condensation will run into the house.