UHA STANDARD UNIT HEATER INSTALLATION OPERATION AND SERVICE MANUAL
16 of 51
Figure 9: Separated Combustion Heater - Vertical and Horizontal Vent Termination
Figure 10: Concentric Vent Box
12" (31 cm)
Minimum from air inlet to vent
termination.
Vent
Termination
Listed Thimble through
Combustible Wall
Vent**
12" (31 cm)
Minimum from wall
to vent termination.
Air Intake
12" (31 cm)
Minimum from air inlet to vent
termination.
Air Intake
Termination
NOTE: Vent supports not shown
Vent**
Air Intake*
12" (31 cm)
Minimum from roof to vent
termination.
Vertical
Option
Horizontal
Option
90°
Bend
Model **Vent Diameter Part Number
UHA[X]S 150 - 400 4" (10 cm) 90502102
Model *Air Intake Diameter Part Number
UHA[X]S 150 - 250 4" (10 cm) 90502102
UHA[X]S 300 - 400 5" (13 cm) 90502105
4" (10 cm) Single
Wall Vent Pipe
(By Others)
Seal joint between single wall
and Type B vent with silicone sealant.
Use 3 sheetmetal
screws equally
spaced around joint.
Use 3 sheetmetal
screws equally
spaced around collar.
Concentric
Vent Box
6" (15 cm) or 8" (20 cm)
Single Wall Inlet Air Pipe
(By Others)
One piece of 4" (10 cm) diameter, 1/4" (6 cm)airspace type
“B” vent. Selkirk Model RV or equivalent. (By others)
Combustion Air
to Heater
Toward
Outside
Exhaust
from Heater
4" (10 cm) or
5" (13 cm)