Raypak HD401 Water Heater User Manual


 
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3. Carefully remove 2-stage solenoid.
4. Skip to Step 9 for LO-fire adjustment only.
5. Locate and remove Lo-fire adjustment cap.
6. Carefully remove the spring & weight.
7. Using an allen wrench, turn clockwise to increase
and counterclockwise to decrease the HI-fire man-
ifold pressure. Heater will not run while adjusting
HI-fire pressure.
8. Carefully place the spring & weight back in before
replacing LO-fire adjustment cap.
9. For LO-fire adjustment, tighten the cap to increase
the pressure, loosen to decrease.
10. When correct settings are set, replace the sole-
noid and tamper screw in place.
Gas Type Conversion on Valve
1. Turn off gas supply at the appliance service level.
2. Remove the pressure regulator cover assembly.
3. Remove the existing stem/spring assembly.
4. Insert the replacement stem/spring assembly.
5. Replace the pressure regulator cover assembly
and tighten screws.
6. Mount conversion labels on the gas valve.
Safety Inspection
Replace main gas manifold adjustment screw cap.
Check all thermostats and high limit settings.
During the following safety checks leave manome-
ters hooked up, check and record.
If other gas fired equipment are in the room and on
same gas main check all pressures on the Hi Delta
SS with all other equipment running.
Check thermostats for ON/OFF operation.
Check High limits for ON/OFF operation.
While in operation, check flow switch operation.
Check the low gas pressure switches (For proper
adjustment, if available, use the attached
manometers to set pressure. The scales on the
switch are approximate only); Low gas pressure
switch (optional) must be set at 3.5 in. WC for nat-
ural gas and 10.5 in. WC for LP gas.
High gas pressure switch (optional) at 1 in. WC
above manifold pressure.
Insert ignition control lockout tests as safety
check.
Fig. 31: Gas Valve Adjustment (Invensys Valve)
Fig. 32: Gas Type Conversion on Honeywell Valve
WARNING: Burner orifices must be changed when
changing gas type.
NOTE: Model HD401 requires replacement of
valve.