Thermo Pride MHA1-50N Installation And Service Manual page 29

All installations and services must be performed by qualified service personnel.
Figure 7: Typical Piping For Two-Stage Regulation
NOTICE: Two-stage regulation must be installed for propane gas when used
with any Thermo Pride propane furnace. See illustration above of a typical two
stage piping system.
Table 5: COPPER TUBING SIZE FOR PROPANE GASES
All black pipe sizes shown are nominal iron pipe sizes.
Seamless copper tubing may only be used with gases that are not corrosive to it.
See note below and check with your LP gas supplier before using. Seamless
copper tubing must comply with standard type K or L for seamless copper water
tube, ASTM B 88; or seamless copper tube for air conditioning field service,
ASTM B 280. Copper tubing sizes for indicated BTU input rates are given above
in Table 5.
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