Form I-RA/D 350/500, Page 16
Draft Inducer (Sizes 350 and 500) and Draft Inducer Relay (Size 500)
(NOTE: A eld-supplied draft inducer may be required on either a Size 350 or Size 500. To install on a
Size 500, a eld-supplied relay is required.)
A eld-supplied UL or CSA/ULC listed draft inducer is required when the draft in the combustion cham-
ber measures less than .01” w.c. on a draft gauge. Unfortunately, the draft cannot be measured until the
heater is operating. A eld provided relay may be used to make the necessary electrical connections to
operate a draft inducer.
Read the following CAUTION and survey the installation for indications that a draft inducer might be
required. A draft inducer may be added at any time, but if a potential need is determined at the time of
installation, the easier method is to include the eld-supplied draft inducer in the original installation. The
draft inducer must be capable of moving at least 450 CFM of ue gas at 500°F.
CAUTION: If there is a backdraft or downdraft, do not continue operation of the heater until
the situation isrected. Equipment and/or property damage could result. Back pressure
(backdraft or downdraft) may be caused by the chimney being lower than surrounding
objects, such as buildings, hills, trees, rooftops, etc., OR by an exhaust fan in the building.
The air intake in the room where the heater is installed must be of sufcient size so there
is no change in the draft reading in the ue with the exhaust fan running.
Be sure to measure the draft when all exhaust fans and systems are operating. When a draft inducer
is installed, a draft proving switch must be used to shutoff the fuel supply to the burner in the event of
failure of the draft inducer. The wiring diagram illustrates the proper wiring of the draft proving switch
and the draft booster.
Draft
Regulator
• Support: The vent system must be adequately supported using non-combustible
strapping or supports to carry the weight of the vent and wind load. Do not use the heater
to provide support for the vent system.
• Vertical Vent: If installing a factory-built vent, follow the manufacturer’s instructions.
If a masonry chimney is used, a thimble that is permanently cemented in place with
high temperature cement should be used to permit easy cleaning of the chimney.
The end of the vent pipe must not extend past the inside wall of the chimney.
• Draft Inducer: If a draft inducer is used, follow the manufacturer’s instructions
and wire the inducer according to the wiring diagram provided. See Optional Draft
Inducer Relay below.
• Terminal End: The vent must terminate at least 3 ft (914mm) above the highest
point of exit and at least 2 ft (610mm) higher than any portion of a building or
obstruction within 10 ft (3M) of the chimney. Install a vent cap on the terminal end
of the vent. A Reznor (Option CC1) or Type L Breidert Air-x-hauster
®
vent cap is
recommended. A different style of vent cap could cause nuisance problems.
Detailed Requirements for the Vent System (cont’d)
A barometric draft regulator is shipped with
this heater and MUST be installed in the ue
near the heater ue opening.
Refer to the illustration for recommended loca-
tions. To install, follow the manufacturer’s in-
structions packaged with the draft regulator.
To Next Page
Loading...