27. High Altitude & Orifice Chart; High Altitude Installation - Schwank P40U Owner's Manual

27. HIGH ALTITUDE INSTALLATION

When this appliance is installed above the altitude stipulated below, the input must be de-rated
by 4% for each 1000 ft . If your local utility supplies gas with a de-rated heat content, no
orifice change is required in the heater . Check with your local utility regarding de-rating.
USA: The factory installed orifice for this appliance is approved for altitudes zero to
2000 feet above sea level. Above 2000 feet, refer to table below.
Canada: The factory installed orifice for this appliance is approved for altitudes zero to
4500 feet above sea level. When installed above 4500 feet, refer to the table below
ORIFICE CHART - ALTITUDE CONVERSION
MODEL NO
Supplied
P40U / P40U-I NG
JS-0731-DM
P40U / P40U-I LPG*
JS-0749-DM
* Field Conversion Kit required to convert between fuel gas types:

Part number: JS-0555-XB P40U - Natural Gas to Propane Gas Conversion Kit

Part number: JS-0555-XA P40U - Propane Gas to Natural Gas Conversion Kit
P40U-F / P40U-IF I&O Manual
IM101220
RD: MAR 2014
RL: 4B
FOR USE AT ALTITUDES ABOVE (FEET)
USA Only
0 2000 3000
31 DMS 3 mm 32DMS
JS-0730-MM JS-0732-DM
49 DMS 50 DMS 50 DMS
JS-0750-DM JS-0750-DM
Gas Orifice Drill Size / Part #
4000 5000
32DMS 33DMS
JS-0732-DM JS-0733-DM
50 DMS 51 DMS
JS-0750-DM JS-0751-DM
40
USA & CANADA*
6000 7000
34DMS 7/64
JS-0734-DM JS-0731-IN JS-0736-DM
51 DMS 51 DMS
JS-0751-DM JS-0751-DM JS-0752-DM
8000
36DMS
52 DMS