Rheem Raypak 207A Installation And Operation Manual page 30

Gas Valve Removal
1. Shut off gas supply to the heater. Remove gas piping
to gas valve inlet.
2. Remove burner tray, following above procedure.
3. Disconnect, pilot tubing from gas valve.
4. Remove (2) screws that mount anti-rotation bracket
to the burner tray.
5. Turn vertical gas pipe from manifold slightly and
unscrew gas valve.
6. Reverse above procedure to reinstall.
Main Burner And Orifice Removal
1. Remove burner tray, following above procedure.
2. Remove pilot. See pilot removal procedure.
3. Remove (8) total screws from the burner hold-down
brackets, front and rear of tray.
4. Remove (8) total screws from the left and right
sides of the manifold assembly. Detach the air/gas
manifold assembly from the burner tray assembly.
5. Remove burners by raising them straight up off the
rear end slots.
6. Use a long 9/16" socket wrench to remove orifice
from the gas manifold.
7. Reverse above procedure to reinstall.
Pilot Removal
1. Disconnect pilot tubing from gas valve.
2. Remove the pilot wire from the pilot assembly.
3. Remove (2) screws that mount the pilot assembly to
the burner tray.
4. Pull the pilot assembly downwards and outwards.
5. Reverse above procedure to reinstall.
.18± .04 inch (4.57±1 mm)
Figure 57. Lo NOx Pilot
30
Combustion Blower Removal
1. Remove the (2) screws that secure the blower box to
the burner tray.
2. Remove (2) screws that mount the blower box to the
base of the heater.
3. Disconnect wire connector from the combustion
blower.
4. Carefully remove blower box with combustion blower.
5. Remove (2) screws that secure combustion blower
to blower box.
6. Reverse above procedure to reinstall.
Heat Exchanger Removal
1. Shut water, gas and electricity off, close valves and
relieve pressure, then remove relief valve. Remove
side access panels.
2. Remove top jacket holding screws.
3. Remove rear top panel.
4. Remove screws mounting the rain shield to the rear
panel. Also remove the screws that mount the rain
shield to the sway brace. Remove rain shield.
5. Remove the four (4) screws holding down the flue
collector. Remove the flue collector.
6. If a ProTek Shield Assy is attached to the heater;
disconnect flange nuts on Inlet/Outlet header,
remove ProTek Shield Assy bonding wire from heat
exchanger stud, loosen union(s) at gas pipe and slide
heater away from piping.
7. Lift heat exchanger straight up using caution not to
damage refractory.
8. Reverse above procedure to reinstall. Make sure the
insulation strips are properly replaced on top of the
refractory retainer.
Tube Cleaning Procedure
Electrode Alignment
Establish a regular inspection schedule, the frequency
Detail
depending on the local water conditions and the severity
of service. Do not let the tubes clog up solidly. Clean out
deposits over 1/16" in thickness.
The heater may be cleaned from the return header
side, without breaking pipe connections. It is preferable,
however, to remove both headers for better visibility
through the tubes and to be sure the ground-up lime dust
does not get into the system. Note that you do not remove
the top panel or the heater exchanger, generally.
After reaming, mount the wire brush in place of the auger
and clean out debris remaining in the tubes.
Another method is to remove the heat exchanger, ream
tubes and immerse heat exchanger in non-inhibited de-
scale solvent for severe scale build-up.