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Page 6
PRODUCT SPECIFICATIONS
Water vapor is a by-product of gas combustion. An unvented room
heater produces approximately one (1) ounce (30ml) of water for
every 1,000 BTU's (.3KW's) of gas input per hour.
Unvented room heaters must be used as supplemental heat (a
room) rather than a primary heat source (an entire house). In most
supplemental heat applications, the water vapor does not create a
problem. In most applications, the water vapor enhances the low
humidity atmosphere experienced during cold weather.
The following steps will help insure that water vapor does not
become a problem.
1. Be sure the heater is sized properly for the application, including
ample combustion air and circulation air.
2. If high humidity is experienced, a dehumidifier may be used to
help lower the water vapor content of the air.
3. Do not use an unvented room heater as the primary heat source
(an entire house).
wATER VAPOR: A By-PRODUCT OF UNVENTED ROOM HEATERS
Model
Gas
Valve Type
Regulator Pressure
Setting
Gas Inlet Pressure
Max
Gas Inlet Pressure
Minimum
VFDR(18,24,30)LB
Natural
Millivolt
3.5" W.C.
10.5" W.C.
4.5" W.C.
Propane
10.0" W.C.
13.0" W.C.
11.0" W.C.
VFDR18LB10
Natural
Millivolt
3.5" W.C.
10.5" W.C.
5.0" W.C.
Propane
10.0" W.C.
13.0" W.C.
11.0" W.C.
VFDT(18,24,30)LB
Natural
Thermostat
6.0" W.C.
10.5" W.C.
7.0" W.C.
Propane
10.0" W.C.
13.0" W.C.
11.0" W.C.
VFDM(18,24,30)LB
Natural
Manual
6.0" W.C.
10.5" W.C.
7.0" W.C.
Propane
10.0" W.C.
13.0" W.C.
11.0" W.C.
Model
BTU/hr.
Max. Rate
BTU/hr.
Med. Rate
BTU/hr.
Min. Rate
Air Shutter Open-
ing
VFDR18LB10N
10,000
N/A
N/A
1/16"
VFDR18LB10P
10,000
N/A
N/A
3/16"
VFDR18LBN
28,000
N/A
19,000
1/8"
VFDR18LBP
28,000
N/A
22,000
5/16"
VFDR24LBN
34,000
N/A
24,000
1/8"
VFDR24LBP
34,000
N/A
26,000
5/16"
VFDR30LBN
40,000
N/A
27,000
1/8"
VFDR30LBP
40,000
N/A
31,000
3/8"
VFDT18LBN
28,000
N/A
19,000
1/8"
VFDT18LBP
28,000
N/A
22,000
5/16"
VFDT24LBN
34,000
N/A
24,000
1/8"
VFDT24LBP
34,000
N/A
26,000
5/16"
VFDT30LBN
40,000
N/A
27,000
1/8"
VFDT30LBP
40,000
N/A
31,000
3/8"
VFDM18LBN
28,000
23,000
19,000
1/8"
VFDM18LBP
28,000
25,000
22,000
5/16"
VFDM24LBN
34,000
29,000
24,000
1/8"
VFDM24LBP
34,000
30,000
26,000
5/16"
VFDM30LBN
40,000
32,000
27,000
1/8"
VFDM30LBP
40,000
36,000
31,000
3/8"
NOTICE
:
Thermostats are for Vent-Free Applications only.
