Roberts Gorden Combat UHD-Series, Installation, Operation & Service Manual

Page: 21 / 70

SECTION 7: V
ENTING
13 of 57
terminals. See Page 16, Figure 10 . As an option, the
vent and air intake are r u n as separate pipes to a
concentric vent box and a concentric vent/air intake
pipe penetrates the
w all or roof. See Page 16,
Figure 11 and Page 17, Figure 12 .
For separated comb u stion installation, the vent and
air intake m u st be fitted w ith an individ u al and
correctly sized sealed system and the vent and air
intake m
u st terminate at approved w all and roof
terminals.
Separated comb u stion u nits may not be common
vented.
7.3 Horizontal Ventin g
Horizontally vented heaters m u st be individ u ally
vented, no common venting.
V ent pipe m u st be sloped ¼" (.6 cm) do w n w ard for
every 1' (.3 m).
In noncomb u stible w alls only, vent terminal (P/N
02537801-1P) may be u sed.
For 4'' (10 cm) vents in either comb u stible or
noncomb u stible w alls, u se vent terminal (P/N
90502100) or eq u ivalent ins u lated vent terminal.
Follo w the man u fact u rer's instr u ctions for proper
installation.
Instead of an ins u lated vent terminal, a listed thimble
w ith 2" (5 cm) air gap may be u sed w ith a 4" (10 cm)
vent cap (P/N 90502102).
7.4 Vertical Ventin g
V ertically vented standard vented heaters can be
common vented ( u p to fo u r heaters).
For 4'' (10 cm) common vent, an approved vent cap
(P/N 90502102) m
u st be u sed.
For 6'' (15 cm) common vent, an approved vent cap
(P/N 90502103) m
u st be u sed.
For common vertical venting of more than t w o
heaters, See Page 15, Figure 9 .
A vent shall not extend less than 2' (.6 m) above the
highest point
w here it passes thro u gh a flat roof of a
b u ilding.
7.5 Maximum Vent Len g ths Table
7.6 Vent Material
V ent material may be single w all 26 ga. (minim u m)
galvanized steel or eq u al thickness stainless steel.
Completely seal all joints, refer to Page 12, Section
7.2 .
If penetrating a comb u stible w all or roof, a listed
thimble w ith 2" (5 cm) clearance m u st be u sed.
Where local codes permit, a single section of type
B-1 vent material may be
u sed at the roof or w all
penetration instead of a thimble. Ens u re vent
man u fact u rer's clearance from vent material is
maintained. Seal ann u lar space of the type B-1 vent
as w ell as all joints in the remaining vent.
Fi g ure 7: Vent and Roof Detail
Model UHD[T][X][S][R] 150 - 250
Model UHD[X][S][R] 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
Roof
Vent
Terminal
Listed Thim b le
Flashing
or Rain Collar
Vent
2" (5 cm) Air Gap
to Com b usti b le
Material