Owner`s manual
supra/primo Manual 
IM091112 
RD: NOV 2009 
RL: 11B - BA 
14 
 WARNING 
9. GAS SUPPLY PIPING 
A.  Gas piping must be sized to provide adequate input capacity to all heaters and appliances 
in the system and at the pressure indicated in Table 3 below. 
IMPORTANT:
 Minimum supply line pressure at the inlet to the heater regu-
lator must not be lower than 6.0 inches of water column pressure for natu-
ral gas and 12” w.c. for propane. The supply gas pressure must be 
checked with all heaters in operation.  
B.  Provide a 1/8 in (3.2 mm) NPT plugged tapping, accessible for test gauge connection, im-
mediately upstream of the gas supply connection to the heater. 
C. It is recommended to install an approved flexible connector between the heater and gas 
piping - available as option from Schwank or from your local supplier. 
D.  A drip-leg prior to the inlet connection to the heater must be provided in the gas line. 
E. On propane-fired units, a main line filter is recommended. 
F.  Piping joint compounds must be resistant to the action of natural gas or LPG 
G.  TEST FOR LEAKS: Apply soap suds solution to all connections and joints and if bubbles 
appear, leaks have been detected and must be corrected. DO NOT USE A MATCH OR 
OPEN FLAME OF ANY KIND TO TEST FOR LEAKS. NEVER OPERATE THE HEATER 
WITH LEAKING CONNECTIONS. Leak test according to local or national codes. 
DO NOT use pressure greater than 1/2 psig to pressure check the heater. 
The supply system should be checked first with heater turned “OFF” followed by another 
check with heater turned “ON”. 
Do not install any gas piping or wiring in the heat zone directly above the heater. 
Do not subject heater controls to leak test pressures when checking the main supply piping. 
 WARNING 
Install and connect gas lines in accordance with lo-
cal, state, provincial and national codes (ANSI 
Z223.1/NFPA 54 in USA; B149.1 in Canada). 
Incorrect installation and connection of gas lines 
may results in fire, explosion, property damage, in-
jury or death 
GAS CONVERSION 
This heater may be field converted from one fuel gas to another (natural gas or 
LPG). Conversion must be accomplished with a kit available from the manufac-
turer . Contact your local distributor for the kit that is specific to the model in-
stalled. Conversion may include changing of the air restrictor as well as the ori-
fice and gas valve spring. Follow the instructions supplied with the conversion kit. 
Gas conversion must only be done by a trained gas service technician, according 
to all local and national codes. Incorrect conversion may result in fire, explosion, 
property damage, injury or death 










