34
cap to the side of the adjacent vent cap(s).
Combustion air supplied from outdoors must be free of
particulate and chemical contaminants. To avoid a
blocked flue condition, keep the vent cap clear of
snow, ice, leaves, debris, etc.
Outdoor Installation
XTherm heaters are certified for outdoor operation in
non-freezing conditions only. Freezing conditions may
cause condensate to freeze in the condensate drain
line and trap causing the unit to shut down from a
blocked condensate drain. Additionally, components of
the condensate management system may be dam-
aged by the ice formation. Units installed in freezing
climates for seasonal use must be winterized to avoid
freeze damage to the heater.
Outdoor models must be vented with listed vent mate-
rial per the following instructions and installed with the
optional factory-supplied outdoor vent kit. A special
vent cap is provided in accordance with CSA require-
ments. It must be installed directly on the vent pipe as
illustrated in Fig. 29 on page 30.
Care must be taken when locating the heater out-
doors, because the flue gases discharged from the
vent cap can condense as they leave the cap.
Improper location can result in damage to adjacent
structures or building finish. For maximum efficiency
and safety, the following precautions must be
observed:
1. Outdoor models must be installed outdoors and
must use the outdoor vent cap and air intake hood
available from the manufacturer (sales order
option D-11).
2. Periodically check venting system. The heater’s
venting areas must never be obstructed in any
way and minimum clearances must be observed
to prevent restriction of combustion and ventilation
air. Keep area clear and free of combustible and
flammable materials.
3. Do not locate adjacent to any window, door, walk-
way, or gravity air intake. The vent must be
located a minimum of 4 ft horizontally from such
areas.
84. Install above grade level and above normal snow
levels.
5. Vent terminal must be at least 3 ft above any
forced air inlet located within 10 ft.
6. Adjacent brick or masonry surfaces must be pro-
tected with a rust-resistant sheet metal plate.
Freeze Protection
To enable freeze protection, dip switch position 7 (on
the PIM™) must be turned on (UP position). This is
the default position.
If the water temperature drops below 45˚F on the
Outlet or Inlet sensors, the Boiler pump is enabled.
The pump is turned off when both the Inlet and Outlet
temperatures rise above 50˚F.
If either the Outlet or Inlet temperature drops below
WARNING:
No substitutions of flue pipe or vent
cap material are allowed. Such substitutions would
jeopardize the safety and health of inhabitants.
NOTE:
The vent cap and air intake hood must be
furnished by the heater manufacturer in accordance
with its listing (sales order option D-11).
NOTE:
Condensate can freeze on the vent cap.
Frozen condensate on the vent cap can result in a
blocked flue condition. Condensate is acidic and
highly corrosive
NOTE:
Centrotherm polypropylene vent material
cannot be used for outdoor installations.
Fig. 29: Outdoor Venting
