3
INSTALLATION RESTRICTIONS
Failure to install, maintain and/or operate the VSUB Blower in accordance with manufacturer's instructions may result in
conditions which can produce bodily injury and property damage.
The VSUB Blower must be installed by a qualified installer in accordance with these instructions and all local codes or in their
absence in accordance with the latest edition of The National Fuel Gas Code (NFPA 54), NFPA 211 or 31 when applicable, the latest
edition of the National Electrical Code (NFPA 70) and the Occupational Safety and Health Act (OSHA) when applicable. In the
absence of local codes in Canada, installations must comply with the Canadian Electrical Code (CSA Std 22.1), the latest edition of
the Natural Gas Installation Code (CAN/CGA-B149.1), the Propane Installation Code (CAN/CGA-B149.2) and the Installation Code for
Oil Burning Equipment (CSA Std B139-M91).
Improper installation can create a hazardous condition such as an explosion, fire, electrical shock or carbon monoxide poisoning
resulting in property damage, personal injury or death.
1. The VSUB Blower is intended to be installed on natural gas, LP-gas or oil-fired heating appliance systems. The VSUB Blower is
not Listed for use on condensing equipment in Canada.
2. The VSUB Blower was tested with exit flue gas temperatures of 575
O
F (300
O
C).
3. The VSUB Blower may not be installed on incinerators, incinerating toilets or solid-fuel burning appliances.
4. The VSUB Blower shall not be installed on an appliance with an automatic valve having a manual opener unless the manual
opener has been rendered inoperative or the automatic valve has been replaced with a valve not equipped with a manual opener.
5. VSUB Blowers not utilizing the Tjernlund CPC-2 Constant Pressure Control may only be installed on appliances equipped
with a draft hood, draft diverter or barometric draft control.
6. Tjernlund’s Model FFP-1, Fire and Freeze Protection Limit must be installed when using the VSUB as a combustion air intake to
protect the boiler room from temperature extremes. Do not install FFP-1 when VSUB is used as a draft inducer. It is designed to
disrupt power to a combustion air supply blower in the event of a boiler room fire or an extended period where frigid outdoor air
supply could cause pipes to freeze.
D
Never operate a mechanical draft or combustion air system without a proving device that proves the flow of flue gasses or combustion
air and is interlocked with all of the heating appliances. If installing a VSUB Blower in conjunction with a CPC-2 controller, the CPC-2
provides the safety interlock. If installing a VSUB Blower without a CPC-2 controller the PSA-1 fan proving switch must be installed in
conjunction with a UC1 Universal interlock control and any additional MAC-Series multiple appliance controls necessary to interlock
all heaters being vented.
IONS
INSTALLER CAUTIONS
Disconnect the power supply when making wiring connections or when working around the fan impeller and motor. Failure
to do so can result in electrical shock, personal injury, death or property damage.
1. The VSUB Blower must be interlocked with the heating appliance burner(s).
2. Plan the vent system so that the code required clearances are maintained from plumbing, wiring and combustibles.
3. Make certain the power supply is adequate for VSUB Blower motor and VFD requirements. Do not add the VSUB Blower to a
circuit where the total load is unknown.
4. The installer must verify that the appliance on which the VSUB Blower will be installed is in a safe operating condition.
Consult appliance manufacturer’s Instructions for details.
5. VSUB Blower housing is single wall. Standard clearances to combustibles must be maintained when venting flue products.
6. VSUB Blowers must use the appropriate Tjernlund VFD model.
REQUIREMENTS WHEN USING THE VSUB BLOWER FOR COMBUSTION AIR INTAKE
Unless properly screened or guarded to prohibit contact with the blower wheel, a minimum of 3' of pipe must be connected to the
inlet/discharge of the VSUB Blower.
Use the FFP-1, Fire and Freeze Protection Limit that was provided in the VSUB Blower. Place this limit in the physical location as
defined in the limit installation instructions and wire into the control circuit as recommended for your type of installation. This limit is
designed to shut off the combustion air supply if excessive heat or extremely cold air is present in the mechanical room. Do not mount
the limit next to hot or cold surfaces or in the flow of the blower discharge.
1. Make sure the VSUB specified is large enough to supply the combustion air for all heating appliances in the mechanical room.
Tjernlund Products, Inc. is not responsible for vent layout, appliance type, size or design changes to the air supply system. The
Mechanical room must be sealed to keep the supplied air from being bypassed to other parts of the building or outdoors. We rec-
ommend that the blower be oversized by 25% to accommodate any unforeseen leakage.
