Bard Bayrd Furnace 403293A - Manual (Page 25)

WARNINOt Failure to install bottom closure
panel could allow combustion products to enter
circulating air stream, resulting In injury or death.
When furnace is installed so that supply air ducts carry
air to areas outside the space containing the furnace,
return air must also be handled by a duct(s) sealed to
furnace casing and terminating outside the space con­
taining furnace.
Avoid vent system reverse pressure by running return
air duct work outside furnace space. Seal return air duct
work to furnace casing, walls, ceilings or floors It passes
through. End duct work outside furnace space.
WARNINOt Failure to seal return air duct work could
allow combustion products to enter circulating air
stream through air stream leaks, resulting in Injury
or death.
C. Duct dampers.
You may balance air flow with dampers installed in each
branch run duct and adjust for even temperature
throughout the heated space. For proper furnace opera­
tion, make sure:
• Supply air registers and return air grilles are
open;
- Rugs, carpets, drapes or furniture are clear of
registers and grilles;
• Size and shape of supply air plenum is correct;
• Number of supply air ducts is correct;
• You consider your own experience and seek as­
sistance if needed.
D. Common duct work.
If furnace will share common duct work with a separate
cooling unit, install furnace parallel to or upstream of
cooling unit. This avoids condensation in heating ele­
ment. Do not install cooling coil in return air duct work.
With parallel flow, dampers or other means must prevent
chilled air from entering furnace. If dampers or other
means are not in full heat or cool position, furnace or
cooling unit must not operate.
SECTION 17 — SELECTING AND INSTALLING
FILTER CABINETS.
CAUTIONS You must Install air filters to keep these
components clean: blower motor, blower wheel and air
conditioning coll, If there le one. Dirty equipment may
reduce system efficiency or cause erratic control perfor­
mance, resulting in damage to blower motor or heat ex­
changer and air conditioner (if installed).
Do not install air filters inside furnace casing.
There are no air filters shipped with this furnace. Obtain and
install correct size filters and proper filter frames. Air velocity
must not exceed 300-teet per minute through low velocity
disposable filters.
Air velocity must not exceed 650-feet per minute through
high velocity cleanable filters. Too small a filter could cause
excess static pressure, adversely affecting furnace and cool­
ing system operation.
Follow minimum sizing and quantity recommendations in Fig­
ure 27, as well as the air filter manufacturer's.
DISPOSABLE AIR
*GAS INPUT ‘MOTOR FILTERS
BTU/HR H.P. (FIELD SUPPLIED)
(Two Required)
SIZE
CLEANABLE AIR
FILTERS
(FIELD SUPPLIED)
(One Required)
SIZE
40,000 1/4 1 4 X 2 5 X 1 1 4 X 2 S X 1
40,000 1/3 1 4 X 2 5 X 1 1 4 X 2 5 X 1
60,000 1/4 1 4 X 2 5 X 1 1 4 X 2 5 X 1
60,000 1/3 1 4 X 2 5 X 1 1 4 X 2 5 X 1
60,000 1/2 1 6 X 2 5 X 1 1 6 X 2 5 X 1
80,000 1/4 1 4 X 2 5 X 1 1 4 X 2 5 X 1
80,000 1/3 1 4 X 2 5 X 1 1 4 X 2 5 X 1
80,000 1/2 1 6 X 2 5 X 1 1 6 X 2 5 X 1
80,000 3/4 20 X 25 X t 20 X 25 X 1
100,000 1/3 1 6 X 2 5 X 1 1 6 X 2 5 X 1
100,000 1 / 2 1 6 X 2 5 X 1 1 6 X 2 5 X 1
100,000 3 / 4 2 0 X 2 5 X 1 2 0 X 2 5 X 1
120,000 1/2 2 0 X 2 5 X 1 2 0 X 2 5 X 1
120,000 3 / 4 2 0 X 2 5 X 1 2 0 X 2 5 X 1
140,000 3/4 20 X 25 X 1 20 X 25 X 1
140,000 3/4 20 X 25 X 1 20 X 25 X 1
•GAS INPUT and MOTOR H.P. can be found on furnace rating
plate.
FIGURE 27
FIGURE 28
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