Roberts Gorden CTH2-125 - Manual (Page 44)

CTH2-S ERIES I NSTALLATION , O PERATION AND S ERVICE M ANUAL
38
8.11 Outside Combustion Air Supply
IMPORTANT: If the building has a slight negative
pressure or corrosive contaminants, such as haloge-
nated hydrocarbons, are present in the air, an outside
combustion air supply to the heater is required. Seal
all combustion air pipe joints.
Use of optional outside combustion air is not recom-
mended with unvented heaters.
The air supply duct may have to be insulated to pre-
vent condensation on the outer surface. The outside
air terminal must not be more than 1' (31 cm) above
the vent terminal.
8.11.1 Length Requirements
Follow the constraints listed on Page 35, Section 8.6.
8.11.2 Vertical Outside Air Supply for Single Heater Installation
8.11.3 Horizontal Outside Air Supply for Single Heater Installation
Description Part Number
Vent Cap 4" (10 cm) 90502300
Description Part Number
Vent Cap 4" (10 cm) 90502300
Band Clamp
(Recommended)
Flex Hose
(Recommended)
Vent Cap W
all
4" (10 cm)
Single Wall Pipe
Burner