Vent Freezing Protection - Nordyne + RC 92+ Installation Instructions Manual

A= 12" Above Roof or Snow Accumulation Level
Vent and combustion air piping may be installed
in an existing chimney which is not in use pro-
vided that:
a. Both the exhaust vent and air intake run
the length of the chimney.
b. The top of the chimney is sealed and
weatherproofed.
c. The termination clearances shown in
Figure 23 are maintained.
d. No other gas fi red or fuel-burning equip-
ment is vented through the chimney.

Vent Freezing Protection

When the vent pipe is exposed to temperatures
Upfl ow Models
A
Collector Box
Left Side
Rotate counter
Drain
clockwise (Step 2)
8"
Clamp
"HARD" J
(Loosen For Step 1)
Drain Tube
(Retighten for Step 3)
Figure 24. Furnace with Condensate Drain Trap Assembly
26
Exhaust
Elbow
Combustion
Air
Intake
A
Figure 23. Vertical Vent Termination
Route to
floor drain.
...OR
Route to
condensate
pump. Keep
downward
slope.
Vent
1"
18" Min.
36" Max.
A
Exhaust
Plumbing Vent Roof Boot
(Typ. Both Pipes)
below freezing, i.e., when it passes through
unheated spaces, chimneys, etc., the pipe
must be insulated with 1/2 inch thick sponge
rubber insulation, Armafl ex-type insulation or
equivalent. Insulating pipe is important to avoid
condensate icing.
For extremely cold climates or for conditions of
short furnace cycles (i.e. set back thermostat
conditions) the last three feet of vent pipe can be
reduced one nominal pipe size provided that the
total vent length is at least 15 feet in length and
the vent is sized in accordance with the venting
requirements (Table 5) before this reduction is
applied. (Example: 3" to 2-1/2" or 2" to 1-1/2")
Smaller vent pipes are less susceptible to freez-
ing, but must not be excessively restrictive.
Downfl ow Models
A
Collector Box
Left
Side
Rotate clockwise
Drain
(Step 2)
8"
Clamp
"HARD" J
(Loosen For Step 1)
Drain Tube
(Retighten for Step 3)
Route to
floor drain.
...OR
Route to
condensate
pump. Keep
downward
slope.