Ventless Crawl With Vacuum

The Humidex is also now being promoted as an air exchanger as well as a basement dehumidifier. The “dehumidifier” function was the first intended use. Had a few “discussions” with the inventor, Mark Lestage, a refrigeration technician with a bit of history in residential air exchangers.

Gave you folks the American dealer website before. Here’s the Canadian homepage:

http://www.humidex.ca/

Just got off the phone with the builder.

He doesn’t know the name of the exact system (typical builder)
the reason for the unit its the most energy efficient to use, it saves on insulation (you only have to put it on the foundation walls not under the floor) Lower heat bill, he also adds the floor stays warmer that would explain the warmer crawl space 64 degrees. He said, in his own home the tile stays so much warmer. It costs about $250 for the HVAC guy to install and its speed is 20cubic feet per min (no bad) It takes the inside air of the house and puts it into the crawl space then spits it out a the other end.
Pretty cool system.

http://www.fantech.net/dryer_boosting.htm

I was looking at the site earlier and also noticed that they do radon mitigation units as well pretty cool stuff.

Unless they damped it down and measured the flows, I’d say it’s moving/exhausting more air and heat than builder says since the fan isn’t seeing much static pressure!!

See: http://www.fantech.net/inline_duct.htm

(1) The system is giving a continual exhaust-only general ventilation/air exchange for the house but with no heat recovery

(2) Does the house have naturally vented heating applainces in the area of the exhaust end of the duct? and does it these areas of the home under negative pressures that might at times back draft an appliance?

Not a system I would put in my home. In the long run, I’d take the insulation under the floors…cheaper and done well…no maintenance or replacement or electricity use.

Just a note: Fantech bought out an HRV manufacturer in Buctouche, New Brunswick where the gent that invented the Humidex used to take care of the UL or CSA testing of prototype units for electrical certification.
The 2 Maritime Provinces of New Brunswick and Nova Scotia, with a total population of about 1.75 million, have 4 major home ventilation manufacturers (3 have well developed HRV lines).

(1) yes

(2) Not in the area of the exhaust. Dint Know the other

This application appears to be a design for a serious moisture problem. I see no reason for the fan. It is an energy hog.

To condition the crawl, the HVAC return can be piped to the outdoors (this stops unconditioned air infiltrating the house and conditions air before use). All crawlspace openings closed (no vent needed as air exfiltration will occur at a sufficient rate from normal construction leakage). A controlled (balanced) HAVC air supply to the crawl to provide a specific positive pressure.

Outdoor air is treated in heating and cooling before entering the house.
A positive air pressure rather than a negative in the crawl. Less chance of contamination. No moisture infiltration during summer humid weather.
Also acts as a positive pressurization Radon Mitigation System.
HVAC system controls moisture in summer.
Blower motor is not needed, or costly to operate. HVAC blower is operating anyway.

A blowing system has more positive issues than a sucking system.

Possibly if the air in the house being blown outward during cold weather is fairly dry. If it contains quite a bit of humidity (from a humidifier especially),it can cause condensation problems in walls and attics. I have seen a north facing roof system rot out over 20 years or so from a furnace mounted humidifier not being properly controlled. It was next door to my ex-partner’s place.