Siebring ROYAL HEAT 240, Instructions Manual

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GAS SUPPLY INFORMATION
This furnace is designed to run on several gas types. Natural and LP are the most
common. Each furnace is set up for one type of gas.
DO NOT attempt to burn another
type of gas without replacing proper burner and gas valve modifications.
1. An Individual shut off valve is required for each furnace before the gas regulator.
2. The heater and its individual shut off valve must be disconnected from the gas supply
piping system during any pressure testing of that system at test pressure in excess of
½ PSIG (3.5kPa).
3. The heater must be isolated from the gas supply piping system by closing it’s own
individual manual shut off valve during any pressure testing of the gas supply piping
system at test pressures less than or equal to ½ PSIG (3.5kPa).
4. A 1/8” NPT, plugged tapping, accessible for test gauge connections, must be installed
immediately upstream from the gas supply connection to the heater.
5. The combustion chamber may be cleaned with compressed air thru the stack opening
and thru the fresh air inlet. (Remove the burner tray.) The burner manifold and
nozzles may be brushed off and cleaned with compressed air. Any blocked nozzles
may be opened by pushing a soft wire through the opening in the nozzle.
DO NOT
enlarge the nozzle orifices.
6. Type of Gas LP Nat.
Max Inlet Supply (to valve) 14 6
Manifold 11 3 ½
Minimum Valve Inlet 11 4 ½
All pressures are measured in “Inches of Water Column” for manifold pressure.
7. To convert from one gas type to another
A. Main Burner Orifices – LP (red colored Manifold) #63 drill size
NAT (plain cast gray manifold) #52 drill size
B. The orifice may be unscrewed and the correct orifices screwed back in.
Pilot Orifice – LP (red colored)
NAT (plain)
C. The entire pilot assembly should be removed and the correct pilot installed. The
pilot line should be aluminum. Gas Valve Regulator Spring – LP (red colored), NAT
(plain).
The large slotted screw on the top of the regulator should be removed to exchange
regulator springs. After any of these changes are made, manifold gas pressure tests
must be made. The gas valve must be adjusted correctly for proper furnace
performance and operation. Water column manometers are preferred over dial type
manometers.
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