Thermo Products ome-72d36 Furnace User Manual


 
All installations and services must be performed by qualified service personnel.
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The preferred location of the outside combustion air intake termination (e.g. an optional stainless
steel intake hood, part no.370183) is through the side of the structure, skirting or enclosure. An
alternate termination location is under the structure in the skirted or crawlspace area providing a
minimum of 50 square inches of free area exists around the perimeter for outside combustion air
to be drawn through. NOTE: Combustion air cannot be drawn from the occupied space of the
home.
The furnace is shipped with a 2” radiator hose, 2” pvc street ell, 3” dia flex hose and clamps. If
combustion air needs to be pulled from the floor, attach the black plastic adapter to the base of
the combustible floor base. Make sure the knock-out has been removed. Use hi-temperature
silicone and screws to secure the adapter. If needed, the combustion air can be pulled from the
rear of the floor base. For this method remove the knock out in the vertical wall and attach the
adapter to this opening as indicated.
The Beckett burner is equipped with a plastic air boot. The 2” radiator hose and 2” pvc street ell
are to be attached to the boot inlet. Use the two smaller clamps to affix the hose to the boot and
the boot to the male end of elbow. After cutting the flexible hose to the appropriate length,
attach it to the street ell and the black adapter using the remaining two clamps.
The material recommended for the combustion air duct under the structure is smooth, round,
galvanized steel duct or schedule 20 PVC pipe. The maximum duct length allowed is equivalent
to 40-feet of straight duct. Reduce this length by 6-feet for the intake hood and each 90-degree
elbow used, and by 3-feet for each 45-degree elbow used the combustion air duct. Flexible,
spiral, or corrugated duct is not recommended, due to the relatively high pressure drop associated
with air movement through this type of passageway.
If the combustion air is preferred thru the roof then kit AOPS7512 is required. The radiator hose
is then placed over the Beckett boot opening and the hose is clamped over the radiator hose and
boot adapter. Attach the other end to the 2-1/2” combustion air pipe that now protrudes out of
the lower right separator panel with remaining clamp. An alternate installation method would be
to secure the 2” pvc street ell to the metal combustion air pipe. Insert the male end with silicone
sealant and then secure with a tek screw. Cut the 3” flex hose to length and attach it with clamp
to female end of street ell. Attach the other end to burner air-boot as described earlier.