Pilot Safety; Burner Tray Removal (Atm); Gas Valve Removal (Atm); Main Burner And Orifice Removal (Atm) - Raypak 206A Installation & Operating Instructions Manual

NOTE: An erratic high limit is often characteristic of an
internal heat exchanger problem, e.g. scale build-up,
defective bypass. Refer to Troubleshooting section
(starting on page 43).
HIGH LIMIT REMOVAL
1. Shut off main electrical
power switch to heater.
2. Remove inlet/outlet
inspection panel.
3. Remove defective high
limit and replace with a
new high limit.
4. Replace inspection panel.
PILOT SAFETY - Millivolt Models
Heaters equipped with the standing pilot (millivolt sys-
tem) have pilot generators which act as a safety
device to shut off the flow of gas to the main burners
and the pilot burner in case the pilot flame is extin-
guished. The pilot burner must be manually re-lighted
to place the heater in operation again. Refer to the
lighting instructions provided on the heater label.
PILOT SAFETY - AFT Models
The heater employs a pilot safety which closes the
main gas valve within 8/10ths of a second whenever
the pilot flame is interrupted. The pilot flame is auto-
matically lit when the device is powered. The heater
performs its own safety check and opens the main
valve only after the pilot is proven to be lit.
BURNER TRAY REMOVAL -
ATMOSPHERIC MODELS
1. Shut off main electrical power switch to heater.
2. Shut off gas upstream of heater.
3. Remove front door.
4. Disconnect gas line from gas valve.
5. Remove (2) screws that mount burner tray to unit,
and (2) screws that secure gas valve to jacket.
6. Disconnect wires that terminate at gas valve.
7. Disconnect hi-tension wire from PC board.
8. Slide out burner tray.
9. Reverse above procedure to reinstall.
GAS VALVE REMOVAL -
ATMOSPHERIC MODELS
1. Shut off gas supply to the heater. Remove gas
piping to gas valve inlet.
2. Disconnect wires, pilot tubing and bleed line, if
required.
3. Remove burner tray from heater.
4. Turn vertical gas pipe from manifold slightly and
unscrew gas valve.
5. Reverse above procedure to reinstall.
MAIN BURNER AND ORIFICE REMOVAL -
ATMOSPHERIC MODELS
1. Remove burner tray.
2. Remove screws and burner hold-down bracket.
NOTE: If the heat exchanger is sooted badly, the
burner hold-down bracket and spacer can become dis-
torted from direct-flame impingement and this usually
necessitates replacement of these parts.
3. Lift burners from slotted spacers and slide from ori-
fices. Clean with a wire brush.
4. Orifices usually do not need to be replaced. To
clean, run either copper wire or wood toothpick
through orifice. Do not enlarge hole. To remove
orifice, use a socket wrench and remove from
manifold. DO NOT overtighten when reinstalling.
PILOT
BURNER
BURNER
HOLD-DOWN
BRACKET

PILOT REMOVAL AND CLEANING

1. Disconnect pilot tubing and wires from gas valve.
2. Remove pilot assembly from burner tray.
3. Remove pilot from bracket.
4. Remove pilot orifice and air opening (Honeywell
MV unit only), and clean with wire or small brush.
CAUTION! Do not enlarge hole in pilot orifice.
5. Reverse above procedure to reinstall.
HONEYWELL MILLIVOLT
PILOT
Pilot
Air
Opening
Orifice
39
GAS VALVE
GAS
ORIFICE
206-406
Atmospheric
ROBERTSHAW MILLIVOLT
PILOT
Pilot
Orifice