Heat recovery ventilators and energy recovery ventilators

Bar graph comparing air ventilation heating costs between electricity and natural gas.

Compare typical annual ventilation air heating costs.
Enlarge image.

Good indoor air quality requires proper ventilation, but the cost of heating, humidifying, and cooling the outside air for ventilation can be expensive.

Heat recovery ventilation (HRV) or energy recovery ventilation (ERV) saves energy by capturing 50 to 80 per cent of the heat that would normally be lost from the outgoing old airstream and transferring it to an incoming fresh airstream.

The difference between an HRV and an ERV

HRVs recover heat through a plate or heat pipe heat exchanger. No humidity is exchanged, as the outgoing and incoming airstreams don’t come in contact with each other.

ERVs recover heat and humidity using a heat wheel or dual core/reverse flow heat exchanger. The outgoing and incoming airstreams come in contact with the same part of the heat exchanger(s), but not each other – this contact lets humidity transfer from one airstream to the other.

Cold weather defrost control strategies

It is very important to select an HRV/ERV that will defrost in our climate. In Manitoba’s extremely cold winters, the cold heat exchange surfaces of HRVs/ERVs can frost up when exhausting warm, humid building air, which can block airflow, disrupt ventilation, and even cause damage to equipment.

Units that rely on electric resistance preheating and/or electric defrost schemes are not available for incentives. Eligible units must have built-in automatic frost control strategies to allow for reliable operation to −40°C.

Incentives

Incentives are available for retrofit projects only. The incentive amount is based on the specific business sector in which the building operates, and whether the building is currently heating ventilation air with electricity or natural gas.

Ventilation rates are based on minimum National Building Code and/or the authority with jurisdiction requirements. Where supply and exhaust airflow rates are not equal, the incentive will be calculated based on the lesser of the 2 rates.
Business sector Incentive (per CFM)
Electric Natural gas
Multi-unit residential buildings/health care $10.00 $5.00
Hotels/restaurants/retail $6.20 $3.10
Office/warehouse/school $3.30 $1.65

Benefits

  • between 50 to 80 per cent lower energy costs;
  • improved occupant comfort;
  • less demand on your heating and cooling system, decreasing size of required equipment;
  • reduced greenhouse gas emissions.
Typical annual savings
Existing ventilation heating fuel Annual savings Incentive Payback with incentive
The examples above apply to a 43-suite apartment building with no heat recovery in its existing ventilation system, and assumes the building’s 3,200 CFM ventilation load will be upgraded with a 70 per cent efficient HRV.
Electrically heated ventilation $10,000 $32,000 3 years
Natural gas heated ventilation $4,600 $16,000 10 years

Eligibility

To be eligible for incentives, all HRVs/ERVs must:

  • be for existing commercial buildings;
  • must operate for a minimum of 1,000 annual full load hours;
  • must have built in automatic frost control strategies to allow for reliable operation to −40°C.

Units delivering ≤300 CFM:

Units delivering >300 CFM:

  • must have a minimum effectiveness of 65 per cent based on the ASHRAE 84-2013 test procedure;
  • must calculate the effectiveness rating at equal airflow rates at design flow conditions.

HRV/ERV systems not eligible for incentives:

  • Systems with electric auxiliary (re-heat) heating coils downstream of the HRV/ERV, when:
    • natural gas heated ventilation air systems are being replaced; or
    • where natural gas heating is considered to be base case;
  • units installed downstream of outdoor air preheating equipment (built-in or otherwise)
  • units with electric resistance defrost heating.
  • units used in industrial ventilation applications.

You must apply for pre-approval before equipment is ordered and before work can begin.

How to take part

You must receive pre-authorization before you purchase or install any equipment. The application process is as follows:

  • Submit your completed HVAC Program Application (PDF, 320 KB) along with the necessary computer printouts (as per the application form) and final shop drawings. Applications must be accompanied by technical data sheets showing catalogue performance data and efficiency ratings.
  • We will pre-approve your application.
  • Install your energy efficient measures.
  • Submit your completed HVAC completion documents (PDF, 231 KB):
    • completion declaration;
    • questionnaire;
    • paid invoices;
    • Final HRV/ERV as-built shop drawings;
    • For units ≤300 CFM: a manufacturer warranty start-up checklist sheet;
    • For units >300 CFM: a Testing and Balance report, provided by an AABC certified firm, documenting measured supply and exhaust airflow rates.
  • We may arrange a post-inspection walk-through.
  • An incentive cheque will be mailed to you.