Raypak RAYTHERM 0180B - Manual (Page 36)

36
Adjustment & Replacement of
Components
Gas valve Replacement
1. Shut-off electrical power and gas supply to the
boiler.
2. Remove gas piping to gas valve inlet.
3. Disconnect wiring connections, pilot tubing (when
present).
4. Remove screws (2) holding the burner tray.
5. Slide burner tray out.
6. Remove gas valve bracket screws and bracket.
7. Unscrew gas valve from gas pipe.
8. Reverse above procedure to re-install.
Gas valve Adjustment - Robertshaw
(Invensys) 7000 Series 2-Stage Gas
valve with Solenoid valve
1. Turn the heater off.
2. Remove the 3/8” nut or the #10 Torx screw.
3. Lift solenoid valve up, keeping the wires connect-
ed to the solenoid valve.
4. If only low fire adjustment is needed, go to Step 9.
5. Using a 3/8” wrench, carefully remove the alu-
minum cap that was under the solenoid
valve-count # of turns when removing the cap.
Be careful not to drop the cylinder (weight) or the
small spring that is under the cap –see Fig. 35.
6. Remove the spring and store in a safe place.
7. Using an Allen wrench, turn the screw clockwise to
increase or counterclockwise to decrease high fire
manifold pressure –see Fig. 35.
8. Install the spring, weight and aluminum cap –tight-
en the cap using same # of turns as was used in
removing the cap.
9. For low fire adjustment, tighten the aluminum cap
to increase and loosen to decrease low fire mani-
fold pressure.
10. Install 2-stage solenoid valve and turn heater on,
check manifold pressures.
11. Repeat steps 3 to 10 until correct manifold pres-
sures are obtained.
12. Secure 2-stage solenoid valve by tightening the
3/8” nut or #10 Torx screw.
DANGER—SHOCK HAZARD: Make sure
electrical power to the boiler is disconnected to avoid
potential serious injury or damage to components.
Pilot Pilot
Orifice
Orifice
Air
Opening
Fig. 36: Pilots, Honeywell (Left) and Robertshaw (Right)
NOTE: Attach a manometer and check the manifold
pressures –both high fire and low fire– before
making any adjustments.
Pilot Burner Cleaning or
Replacement (Standing Pilot)
1. Shut-off electrical power and gas supply to the
boiler.
2. Disconnect gas piping to gas valve.
3. Disconnect wiring connections to gas valve.
4. Remove screws (2) holding the burner tray.
5. Slide burner tray out.
6. Remove screw holding pilot lighter tube.
7. Remove screws (2) holding pilot bracket on the
burner tray.
8. Disconnect thermocouple and pilot tubing from the
gas valve.
9. Remove pilot burner from pilot bracket.
10. Remove pilot orifice and blow away lint or dirt.
Clean with wire or small brush. NOTE: Make sure
pilot orifice is clear, but do not enlarge the hole.
11. Reverse above procedure to re-install.
Fig. 35: 2-Stage Gas Valve Adjustment (Invensys)