Heat Recovery Ventilators (HRVs) and Energy Recovery Ventilators (ERVs)
Good ventilation characteristics are important to maintaining a healthy building. Excessive ventilation results in unnecessary heat losses and higher greenhouse gas emissions; inadequate or poorly balanced ventilation can result in poor air quality and a higher risk of condensation and mould growth. Having optimised ventilation rates, it is then possible to make further savings by means of heat recovery ventilation: in winter, warm extract air is used to preheat incoming ventilation or furnace input air. [Typically, an HRV recovers only sensible heat, and an ERV also collects latent heat from condensed water vapour.]
It is important that your house be as well-sealed as possible before installation of one of these units.
What to look for:
Consider the following when selecting an HRV or ERV:
Proper Sizing
Make sure that the unit you choose is appropriately sized for your house. You should aim for about 0.5 air changes per hour (a.c.h.). [Manufacturers often express this in cubic feet per minute (cfm): to convert 0.5 a.c.h. to cfm for your house, calculate the internal volume of your house, including basement, and multiply by 30.]
Effectiveness Ratio
Your supplier should be able to give you a percentage figure for the proportion of outgoing heat recovered. A good unit achieves better than 80%.
Government Grants
Grants are available, both for air sealing of your house and for HRVs/ERVs, from two government programmes: EnerGuide for Houses (Saskatchewan) and ecoEnergy Retrofit (federal).
Criteria
Vendors
| Pioneer Co-operative Association Ltd | Swift Current, SK | (306) 778-8883 |
| Nu-Trend Industries Inc. (Venmar) | ||
| Eneready Products Ltd | Burnaby, BC | (604) 433-5697 |
| VanEE / Venmar Ventilation inc. | Drummondville, PQ | (819) 477-6226 |
| Lifebreath: Nutech Brands Inc. | London, ON | (519) 457-1904 |
| Regina Geothermal & Solar Inc | Regina, SK | (306) 591 2243 |
| Venmar CES Inc | Saskatoon, SK | (306) 242-3663 |
| Suntech Systems Ltd | Saskatoon, SK | (306) 664-3060 |
| Air2000 | St Leonard, PQ | (819) 399-3400 |
| Nu-Air Ventilation Systems | Windsor, NS | (902) 798-2261 |