11
Combustion Air Filter
This heater is supplied with an integral combustion air
filter. This filter will reduce the amount of particulates
passed through the combustion system and heat
exchanger but will not protect against chemical air
contamination (See Appendix). The filter must be
checked periodically to verify that adequate combus-
tion air is being supplied to the heater. See the
Maintenance section of this manual for information on
checking the filter and establishing service intervals.
Direct Vent
If outside air is drawn through the intake pipe directly
to the unit for combustion:
1. Install combustion air direct vent in accordance
with Fig. 35 (horizontal) or Fig. 36 (vertical) of this
manual (pages 33 and 34, respectively).
2. Ventilation of the space occupied by the heater(s)
is recommended and can be provided by an open-
ing(s) for ventilation air at the highest practical
point communicating with the outdoors. The total
cross-sectional areas should be at least 1 in.² of
free area per 20,000 BTUH (111 mm² per kW) of
total input rating of all equipment in the room,
when the opening is communicating directly with
the outdoors or through vertical duct(s). The total
cross-sectional area should be at least 1in.² of free
area per 10,000 BTUH (222 mm² per kW) of total
input rating of all equipment in the room, when the
opening is communicating with the outdoors
through horizontal duct(s). Damage to the equip-
ment due to inadequate ventilation of the space is
not a warrantable failure.
3. In cold climates, and to mitigate potential freeze-
up, Raypak highly recommends the installation of
a motorized sealed damper to prevent the circula-
tion of cold air through the heater during the
non-operating hours.
4. Remove the debris screen (or cover panel for
model 1005) by removing the six screws holding it
in place.
5. Install the intake air collar using the six screws
removed in step 8 above.
6. Replace all the access panels.
7. Install combustion air direct vent in accordance
with Fig. 27 (horizontal) or Fig. 28 (vertical) of this
manual (pages 27 and 28, respectively).
8. Ventilation of the space occupied by the heater(s)
is recommended and can be provided by an open-
ing(s) for ventilation air at the highest practical
point communicating with the outdoors. The total
cross-sectional areas should be at least 1 in.² of
free area per 20,000 BTUH (111 mm² per kW) of
total input rating of all equipment in the room,
when the opening is communicating directly with
the outdoors or through vertical duct(s). The total
Debris Screen
Fig. 11: Remove the Debris Screen
Intake Air Collar
Fig. 12: Install the Intake Air Collar
