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Therma Grow™ Greenhouse Heaters
Owner’s Manual • Therma Grow™
5
This Owner’s Manual includes accessories commonly
used on this heater. These accessories must be
ordered seperately.
When calling for technical service assistance, or for
other specific information,
always
have model
number and serial number available. This information
is contained on the dataplate.
This manual will instruct you in the operation and care
of your unit. Have your installer review this manual
with you so that you fully understand the heater and
how it functions.
Contact your local L.B. White distributor or the
L.B. White Company, LLC for assistance, or if you
have any questions about the use of the equipment
or its application.
The L.B. White Company, LLC has a policy of con-
tinuous product improvement. It reserves the right to
change specifications and design without notice.
General Information
HW120 STD HW120 PLUS HW220 STD HW220 PLUS
Maximum Input (btu/h / kW)
120,000 / 35.2
220,000 / 64.5
Minimum input (btu/h / kW)
N/A
65,000 / 19.0
N/A
120,000 / 35.2
Indoor Mounting Air Ex-
change Requirements
(1)
Exhaust Fan
(cfm / m3 / hour)
300 / 510
550 / 934.5
Shuttered Air Inlet
(sq. in. / sq. cm.)
120 / 774
Outdoor Mounting Air
Exchange Requirements
Shuttered Exhaust
Outlet (sq. in. / sq.
cm.)
120 / 774
550 / 934
Inlet Gas Supply Pressure
Acceptable at the Inlet of
the Heater for Purpose
of Input Adjustment (In.
W.C./kPa)
LP Gas
Max.
13.5 / 3.36
Min.
11.0 / 2.74
Nat. Gas
Max.
11.0 / 2.74
Min.
7.0 / 1.74
Burner Manifold
Pressure (in. W.C. / kPa)
LP Gas
Max.
5.0 / 1.24
Min.
N/A
1.4 / 0.35
N/A
1.4 / 0.35
Nat. Gas
Max.
3.1 / 0.77
Min.
N/A
0.8 / 0.20
N/A
0.8 / 0.20
Fuel Consumption Per
Hour
LP Gas
Max.
5.56 lbs / 2.52 kg
10.19 lbs. / 4.62 kg
Min.
N/A
3.01 lbs. /
1.36 kg
N/A
5.56 lbs. /
2.52 kg
Nat. Gas
Max.
120 cu. ft. / 3.42 m3
220 cu. ft. / 6.28 m3
Min.
N/A
65 cu. ft. /
2.53 m3
N/A
120 cu. ft. /
3.42 m3
Motor Characteristics
H.P. / Watts /RPM
Ball Bearing
1/3 / 246 / 1,100
1/2 / 372.8 / 1,100
Electrical Supply
(Volts/Hz/Phase)
115 / 60 / 1
YES
230 / 60 / 1
N/A
YES
Amp Draw
(Includes Ignitor)
Starting
115 volt motor
11.8
17.1
230 volt motor
N/A
6.7
Continuous
Operation
115 volt motor
4.5
8.4
230 volt motor
N/A
2.6
Dimensions (in. / cm) L x W x H
30.75 x 21.28.25 / 78.1 x 53.3 x 71.75
35 x 25 x 30 / 89 x 63.5 x 76.2
Minimum Safe
Distances from Heater
to Nearest Combustible
Materials
Top
1 ft. (0.3 m)
Sides
1 ft. (0.3 m)
Back
1 ft. (0.3 m)
Blower Outlet
6 ft. (1.83 m)
Gas Supply
Propane (L.P.) Gas Supply - 6 / 1.83 Natural Gas Supply - N/A