RATINGS ........................................................................... 6
Gas Conversions ......................................................... 14-15
Model 400 - 500 .......................................................... 14
Direct Venting Options ..................................................... 16
Sizing ............................................................................... 18
PVC/CPVC .................................................................. 20-21
Polypropylene ................................................................... 22
Hazard defi nitions
The following defi ned terms are used throughout this manual to bring attention to the presence of hazards of various risk levels
or to important information concerning the life of the product.
DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious
DANGER
injury.
WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious
WARNING
injury.
CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
CAUTION
injury.
CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not
CAUTION
avoided, may result in property damage.
NOTICE indicates special instructions on installation, operation, or maintenance that are important but not
NOTICE
related to personal injury or property damage.
2
Contents
Natural Gas ...................................................................... 49
Propane Gas .................................................................... 49
Gas Pressure ................................................................... 51
Condensate Drain ............................................................ 56
10. STARTUP ............................................................. 57-62
General ............................................................................. 63
Cascade ........................................................................... 66
Wiring Diagram ........................................................... 78
Ladder Diagram ......................................................... 79
Revision Notes .................................................. Back Cover