HRV/ERV Installation

Select Energy or Heat Recovery Ventilators (ERV/HRV) that are ENERGY STAR^®, equivalent, or better

Install all electrical wiring according to manufacturer specifications and applicable code

Terminate exhaust system to the outdoors, which does not include unconditioned spaces such as attics and crawl spaces that are ventilated with the outdoors

Install terminations: A minimum of 3' away from any property line; A minimum of 3' away from operable opening to houses; A minimum of 10' away from mechanical intake; Above the snow-line

If the termination is at the soffit, seal soffit vents within 6' of the termination

Install intake to pull air from the outdoors, which does not include unconditioned spaces such as attics and crawl spaces that are ventilated with the outdoors

Install intake:

A minimum of 6" from grade;

A minimum of 10' from contaminant sources or exhaust outlets;

Above local snow or flood line;

A minimum of 18" above an asphalt based roof;

Never on a flat roof

Install corrosion resistant screen, louver, or grille material over exterior terminations with a hole size of no less than 1/4" and no greater than 1/2" in any direction

Install interior intakes a minimum of 10' from interior fresh air supplies, cooking surfaces, or combustion appliances

Install interior fresh air supply:

near high traffic areas and occupied spaces (e.g., living rooms, hallways, bedrooms)

not within 10' of interior exhaust intakes

If combining ducts, combine them on the upstream side of fan using "Y"-fittings or collection boxes

Do not combine/connect dryer, kitchen, or garage exhaust streams with any other exhaust stream

All mechanically-supplied outdoor air must pass through a filter before combining with conditioned air

Filtration must meet a minimum efficiency of MERV 8

Filter or air cleaning systems that intentionally produce ozone are not allowed.

Mount ventilator using mechanical fasteners per manufacturer's specifications and applicable code (e.g., seismic restraints)

Isolate unit from the building framing unless specifically designed to be directly attached

Seal all air moving portions of the system using UL 181 products without interfering with the function of dampers

If unit has a condensate drain, connect drain according to manufacturer specifications to a drain location approved by applicable code

Insulate all condensate lines outside the thermal boundary to a minimum of R-4

Ensure fan, service disconnect switch, filters, and drains are accessible for maintenance according to NEC, or applicable building code

If fire dampers are required in the fresh air supply duct, install them according to applicable building code

Fire dampers must be accessible for inspection and/or testing

Sealing activities must not interfere with the operation of fire dampers, balancing dampers, or backdraft dampers

Adjust fan speed, dampers, and registers until the incoming air volume is equal to the outgoing air volume

If the HRV/ERV is ducted to the air handler, balance it with the air handler running

In climate zones 6B, 7, and 8 (as defined by ASHRAE 62.2) do not install ERVs unless they are equipped with frost controls

In climate zones 0A, 1A, 2A (as defined by ASHRAE 62.2) it is preferential to install an ERV rather than an HRV

Do not terminate ventilation air intake at the roof

Determine whether net latent load from ventilation (both natural and mechanical) requires dehumidification; if so, install dehumidification