Raypak XTherm 1005A Installation And Operation Manual page 10

3.5.2. 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 combustion air is being supplied to
the heater. See the Maintenance section of this manual for
information on checking the filter and establishing service
intervals.
3.5.3. Ducted Combustion Air
Combustion air may be ducted directly to the heater using
PVC, CPVC or sealed single-wall galvanized ducting.
The resulting installation meets the requirements for a
direct-vent installation. See venting section for detailed
information.
1. Install combustion air duct in accordance with
Figure 38 and Figure 39.
2. Ventilation of the space occupied by the heater(s)
is required and can be provided by an opening(s)
for ventilation air at the highest practical point
communicating with the outdoors. The total cross-
sectional areas must 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 must
be at least 1 in.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 equipment 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 circulation
of cold air through the heater during the non-
operating hours. Such a damper must be electrically
interlocked to the unit(s) such that a call for heat from
any connected unit will energize the damper, but no
connected unit is allowed to fire until the damper
proves fully open.
3.5.4. Installation Instructions
1. Turn off all power to the heater. All necessary parts
are provided with the appliance.
2. Ensure that the heater is cool to the touch before
proceeding with the installation.
3. Remove both the left and right rear side access
panels.
4. From the right-rear side access area, install the
inside air intake cover panel using the nine hex-head
screws provided. See Figure 8.
10
Inside Air Intake
Cover Panel
Figure 8. Install the Inside Air Intake Cover Panel
5. Optional—For applications where condensation
may form on cold intake air ducting, install the
condensate drip pan to the bottom of the air filter
box using the four screws provided (verify that the
pan is angled slightly downward toward the rear of
the heater as shown in Figure 9).
Condensate
Drip Pan
Figure 9. Install the Condensate Drip Pan
6. Remove the air intake cover panel by removing the
five Phillips head screws holding it in place.
Air Intake
Cover Panel
Figure 10. Remove the Air Intake Cover
Air Filter
Access
Panel