Although the VHR recovers most of the exhaust energy, it is usually necessary to provide supplementary heating or cooling in order to satisfy the room thermostat.

A variety of factory and field installed options are available to provide the supplementary heating and cooling needed for most installations.

Required capacity and engineering data is shown in the tables that follow. Dimensions of field installed heaters or coils will be furnished on request.

HEATING - Factory installed in VHR

Steam or Hot Water  Coils

Note: Coils are factory mounted and piped down through drain pan. Steam or hot water valves and motors can be furnished for field piping and wiring. Coils can be controlled either by space thermostat or discharge air controller. Contact factory for capacity and pressure drop information.

Electric Heater

Note: UL listed electric heaters are factory installed and wired complete with temperature controls. up to 10-steps of modulation is available and can be controlled either by space thermostat or discharge air controller. See Bulletin SBE-1 for electric heater specifications.

HEATING - Field installed in ductwork

INDIRECT FIRED

Indoor Gas Duct Furnace

For Natural Gas or Propane

Note: Multiple identical furnaces may be combined for greater heating capacity. See Bulletin SD-1 for additional information.

Rooftop Gas Duct Furnace

For Natural Gas Or Propane

Note: Use prefix "RDG" for gravity vent and "RDV" for power vent. Multiple identical furnaces may be combined for greater heating capacity. See Bulletin RD-1 for additional information.

OIL OR GAS/OIL: Contact Factory

DIRECT FIRED

Model SBDF Direct Gas-Fired Duct Furnace

When using a direct gas-fired burner as supplementary heat it is often recommended that a SBD unit with blower and burner be transitioned to the heat recovery unit. The VHR is located upstream of the SBD unit and is furnished less supply blower. This has the advantage of the direct gas-fired burner being located on the suction side of the blower avoiding stratification of the heated air. See Bulletin SBD-1 for complete information on the SBD unit.

Model SBD Direct Gas-Fired Unit.

Both weatherproof and indoor direct gas-fired duct furnaces are available in a wide range of sizes and capacities. All electric and safety controls can be furnished with these duct furnaces that are available with the SBD units. See Bulletin SBD-1 for details.

COOLING - Factory or Field installed

Direct expansion and chilled water cooling coils are available. Contact factory for complete details.