Sterling TF User Manual
Page 20
20
TUBULAR UNIT HEATER
HIGH ALTITUDE DERATION
This Tubular Unit Heater has been manufactured utilizing
standard burner orifi ces and a normal manifold pressure
setting as per the specifi cations shown on your unit rating
plate.
All unit deration must be done through fi eld adjustments
by a qualifi ed technician. Once the proper adjustments
Table 6A
Altitude
Manifold Pressure
BTU Output
1
Natural Gas
2
Liquid Propane
3
Feet
Meters
Inches WC
Pa
Inches WC
Pa
Percentage
0-2,000
0-610
3.5
872
10
2,491
100%
2,001-3,000
611-915
3.2
797
9.2
2,292
96%
3,001-4,000
916-1,220
2.9
722
8.4
2,092
92%
4,001-5,000
1,221-1,525
2.7
673
7.7
1,918
88%
5,001-6,000
1,526-1,830
2.4
598
7
1,744
84%
6,001-7,000
1,831-2,135
2.2
548
6.4
1,594
80%
7,001-8,000
2,136-2,440
2
498
5.7
1,420
76%
8,001-9,000
2,441-2,745
1.8
448
5.1
1,270
72%
9,001-10,000
2,746-3,045
1.6
399
4.6
1,145
68%
Notes:
1. Deration based on ANSI Z223.1 (NFPA 54).
2. Table based on heating value of 1,050 BTU/Cu. feet at sea level.
3. Table based on heating value of 2,500 BTU/Cu. feet at sea level.
4. Consult local utility for actual heating value.
Altitude
Manifold Pressure
BTU Output
1
Natural Gas
2
Liquid Propane
3
Feet
Meters
Inches WC
Pa
Inches WC
Pa
Percentage
0-2,000
0-610
3.5
872
10
2,491
100%
2,001-3,000
611-915
3.2
797
9.2
2,292
96%
3,001-4,000
916-1,220
2.9
722
8.4
2,092
92%
4,001-4,500
1,221-1,371
2.8
697
7.9
1,968
90%
Notes:
1. Deration based on CGA 2.17-M91
2. Table based on heating value of 1,050 BTU/Cu. feet at sea level.
3. Table based on heating value of 2,500 BTU/Cu. feet at sea level.
4. Consult local utility for actual heating value.
High Altitude Deration - United States
High Altitude Deration - Canada
are made in the fi eld, attach label #J17-06459 to the unit,
and record adjusted manifold pressure, altitude of the
unit installation and the technician’s name and date on
the label using a permanent marker.
Refer to Installation Instruction section on Adjustments-
Gas Input Rate for adjusting the manifold pressure.