Nortek MG1 Series, Installation Instructions Manual

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26
NATURAL GAS - HIGH HEATING VALUE
ALTITUDE ABOVE
SEA LEVEL
FURNACE MODELS
MANIFOLD PRESSURE IS 3.5 IN WC
(GAS VALVE SETTINGFOR NAT. GAS)
MG1-056 MG1-070 MG1-077 MG1-090
0 to 1,999 FT 29 24 21 17 Factory Orifice Size
2,000 to 2,999 FT 29 26 23 18 Service Orifice Size
3,000 to 3,999 FT 30 26 24 19 Service Orifice Size
4,000 to 4,999 FT 30 27 25 20 Service Orifice Size
5,000 to 5,999 FT 30 28 26 21 Service Orifice Size
6,000 to 6,999 FT 30 28 27 22 Service Orifice Size
7,000 to 7,999 FT 31 29 27 23 Service Orifice Size
8,000 to 8,999 FT 31 29 28 24 Service Orifice Size
9,000 to 9,999 FT 32 30 29 25 Service Orifice Size
Table 12. High Altitude Deration Chart for Natural Gas - High Heating Value
NATURAL GAS - LOW HEATING VALUE
ALTITUDE ABOVE
SEA LEVEL
FURNACE MODELS
MANIFOLD PRESSURE IS 3.5 IN WC
(GAS VALVE SETTINGFOR NAT. GAS)
MG1-056 MG1-070 MG1-077 MG1-090
0 to 1,999 FT 29 24 21 17 Factory Orifice Size
2,000 to 2,999 FT 29 24 20 17 Service Orifice Size
3,000 to 3,999 FT 29 25 21 18 Service Orifice Size
4,000 to 4,999 FT 29 26 22 19 Service Orifice Size
5,000 to 5,999 FT 30 27 23 20 Service Orifice Size
6,000 to 6,999 FT 30 27 24 21 Service Orifice Size
7,000 to 7,999 FT 30 28 25 22 Service Orifice Size
8,000 to 8,999 FT 31 29 26 23 Service Orifice Size
9,000 to 9,999 FT 31 29 27 24 Service Orifice Size
Table 13. High Altitude Deration Chart for Natural Gas - Low Heating Value
Table 11. Natural Gas Heating Values
LOCAL HEATING VALUES FOR NATURAL GAS
ALTITUDE
ABOVE
SEA LEVEL
BTU PER CUBIC FOOT
650 700 750 800 850 900 950 1,000 1,050
2,000 FT LOW LOW LOW LOW LOW LOW
HIGH HIGH HIGH
3,000 FT LOW LOW LOW LOW LOW LOW
HIGH HIGH HIGH
4,000 FT LOW LOW LOW LOW LOW HIGH HIGH HIGH HIGH
5,000 FT LOW LOW LOW LOW LOW HIGH HIGH HIGH HIGH
6,000 FT LOW LOW LOW LOW
HIGH HIGH HIGH HIGH HIGH
7,000 FT LOW LOW LOW LOW HIGH HIGH HIGH HIGH HIGH
8,000 FT LOW LOW LOW
HIGH HIGH HIGH HIGH HIGH HIGH
9,000 FT LOW LOW LOW HIGH HIGH HIGH HIGH HIGH HIGH
10,000 FT LOW LOW HIGH HIGH HIGH HIGH HIGH HIGH HIGH
PROPANE GAS
ALTITUDE ABOVE
SEA LEVEL
FURNACE MODELS
MANIFOLD PRESSURE IS 10 IN WC
(GAS VALVE SETTINGFOR LP GAS)
MG1-056 MG1-070 MG1-077 MG1-090
0 to 1,999 FT 45 42 40 36 Conversion Orifice Size
2,000 to 2,999 FT 47 42 41 37 Service Orifice Size
3,000 to 3,999 FT 47 43 42 38 Service Orifice Size
4,000 to 4,999 FT 47 43 42 39 Service Orifice Size
5,000 to 5,999 FT 48 44 43 40 Service Orifice Size
6,000 to 6,999 FT 48 44 43 41 Service Orifice Size
7,000 to 7,999 FT 49 44 43 42 Service Orifice Size
8,000 to 8,999 FT 49 45 44 42 Service Orifice Size
9,000 to 9,999 FT 50 46 45 43 Service Orifice Size
NOTES: Includes 4% Input Reduction for Each 1,000 Feet. Reference Sources: ANSI Z223.1, CSA B149.1, NFPA 54, National Fuel Gas Code.
Table 14. High Altitude Deration Chart for Propane Gas