21
LP Conversion Kit for RTU Series
LP/Natural Gas conversion kits are used to convert from one gas type to another in the field. This kit is
used on all RTUs, and the part numbers in
should be used on furnace sizes listed.
Kits contain:
• Main Safety Gas Valve Regulator Spring
• Furnace orifices marked with orifice size
This unit is configured for the gas type listed on the nameplate. To convert gas types, you must use the
following parts listed in
. The size-specific parts include the orifice conversion parts and the
combination gas valve spring(s). These parts are available by contacting the
Parts & Service Department
at 1 (866) 784-6900
. All field gas piping must be pressure/leak tested before unit operation. Use a
noncorrosive bubble forming solution or equivalent for leak testing. The equipment and its individual shut-
off valve must be disconnected from the gas supply piping system during any pressure testing of that
system at test pressures in excess of 1/2 psi. The equipment must be isolated from the gas supply piping
system by closing its individual manual shutoff valve during any pressure testing of the gas supply piping
system at test pressures equal to or less than 1/2 psi. This must be performed on an annual basis.
Table 9 - Gas Conversion Kit Part Numbers
Size 1 Units
Furnace Size
50 MBH
75 MBH
100 MBH
125 MBH
150 MBH
200 MBH
Natural Gas
NAT-HMG50
NAT-HMG75
NAT-HMG100
NAT-HMG125
NAT-HMG150
NAT-HMG200
LP Gas
LP-HMG50
LP-HMG75
LP-HM100
LP-HM125
LP-HM150
LP-HM200
Modulating Valve
E50-1/2”
Size 2 and 3 Units
Furnace Size
50 MBH
100 MBH
150 MBH
200 MBH
250 MBH
300 MBH
400 MBH
500 MBH
Natural Gas
NAT-HMG50 NAT-HMG100 NAT-HMG150 NAT-HMG200 NAT-HMG250 NAT-HMG300 NAT-HMG400 NAT-HMG500
LP Gas
LP-HMG50
LP-HM100
LP-HM150
LP-HM200
LP-HM250
LP-HM300
LP-HM400
LP-HM500
Modulating Valve
E50-3/4”
E60-1”
Size 4 Units
Furnace Size
200 MBH
300 MBH
400 MBH
500 MBH
600 MBH
Natural Gas
NAT-HMA200
NAT-HMA300
NAT-HMA400
NAT-HMA500
NAT-HMA600
LP Gas
LP-HMA200
LP-HMA300
LP-HMA400
LP-HMA500
LP-HMA600
Modulating Valve
E50-3/4”
E60-1”