Addison UHAS 150, Installation, Operation & Service Manual

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UHA S
TANDARD
U
NIT
H
EATER
I
NSTALLATION
O
PERATION AND
S
ERVICE
M
ANUAL
12 of 59
7.2.1 Standard Vented Heaters
(Models UHA[T][X] 150-250 and Models UHA[X]
300-400)
The vent must be fitted with a low resistance
terminal. See Page 13, Figure 5 through Page 15,
Figure 7 . Standard vented heaters do not allow
outdoor air intake for combustion air.
7.2.2 Separated Combustion Heaters
(Models UHA[T][X]S 150-250 and Models
UHA[X]S 300-400)
The heaters are designed to be installed as
separated combustion heaters. The vent and air
intake are run as separate pipes to the wall or roof
terminals.
See Page 16, Figure 8 . As an option, the
vent and air intake are run as separate pipes to a
concentric vent box and a concentric vent/air intake
pipe penetrates the wall or roof.
See Page 16,
Figure 9 and Page 17, Figure 10 .
For separated combustion installation, the vent and
air intake must be fitted with an individual and
correctly sized sealed system and the vent and air
intake must terminate at approved wall and roof
terminals.
Separated combustion units may not be common
vented.
7.3 Unvented Operation
WARNING
Carbon Monoxide Hazard
Heaters may be installed
vented or unvented.
Vented heaters must be
vented outdoors.
Unvented heaters must be
installed according to the
installation manual.
Failure to follow these
instructions can result in
death or injury.
This heater is not approved to be installed in
residential buildings.
For unvented operation in commercial installations,
sufficient ventilation must be provided in the amount
of 4 cfm per 1000 Btu/h firing rate (United States); 3
cfm per 1000 Btu/h firing rate (Canada).
7.4 Horizontal Venting
Horizontally vented heaters must be individually
vented, no common venting.
Vent pipe must be sloped ¼" (.6 cm) for every 1' (.3
m).
In noncombustible walls only, vent terminal
(P/N 02537801-1P) may be used.
For 4'' (10 cm) vents in either combustible or
noncombustible walls, use vent terminal (P/N
90502100) or equivalent insulated vent terminal.
Follow the manufacturer's instructions for proper
installation.
Instead of an insulated vent terminal, a listed thimble
with 2" (5 cm) air gap, may be used with a 4" (10 cm)
vent cap (P/N 90502102).
7.5 Vertical Venting
Vertically vented standard vented heaters can be
common vented (up to 4 heaters).
Vent pipe must be sloped 1/4'' (.6 cm) for every
1' (.3 m).
For 4'' (10 cm) common vent, an approved vent cap
(P/N 90502102) must be used.
For 6'' (15 cm) common vent, an approved vent cap
(P/N 90502103) must be used.
For common vertical venting of more than two
heaters,
See Page 15, Figure 7 .
A vent shall not extend less than 2' (.6m) above the
highest point where it passes through a flat roof of a
building.
7.6 Maximum Vent Lengths Table
Model UHA[T][X][S]150-250
UHA[X][S]300-400
# of Elbows
30 ft (9.1 m) 1
25 ft (7.6 m) 2
20 ft (6.1 m) 3
15 ft (4.5 m) 4
10 ft (3.0 m) 5
7.7 Vent Material
Vent material may be single wall 26 ga. (minimum)
galvanized steel or equal thickness stainless steel.
Completely seal all joints, refer to
Page 11, Section
7.2 .
If penetrating a combustible wall or roof, a listed
thimble with 2" (5 cm) clearance must be used.
Where local codes permit, a single section of type
B-1 vent material may be used at the roof or wall
penetration instead of a thimble. Ensure vent
manufacturer's clearance from vent material is
maintained. Seal annular space of the type B-1 vent
as well as all joints in the remaining vent.