Service manual

06/2010
5. Use the 7/8 wrench on the modulating valve hex to unscrew the valve and pipe nipple from
the burner manifold. Then separate the pipe nipple from the valve.
6. To replace the coil only remove the C clip from the modulating valve tube, slide the coil off
and install replacement coil. Make sure the direction arrow is pointed toward the manifold.
Reinstall C clip.
7. USE AGA-APPROVED SEALANT ON ALL GAS THREAD CONNECTIONS. Assemble the
pipe unto the new modulating valve and into the manifold. Take care not to get any thread
sealant into the modulating valve because this will cause the valve to stick.
8. Re-assemble the heater reversing the procedure of steps 5, 4, 3, and 2.
9. Check for gas leaks.
10. Check the unit for normal operation per SM500-16 ‘Testing the RV500’. Note that the
AutoCal procedure (SM500-15) must be run.
Kit Parts List:
1076 Modulating Valve assembly
Figures:
Figure-3 Frontal View of RV500 with Door Removed
Figure-4 View of Electronic Drawer
Model: RV500-F-L / RV501-F-L
SM500-15A Automatic Calibration (Auto Cal) Procedure
For auto calibration of all board units manufactured after April 25, 1999
Other service documents required:
SM500-16 Testing the RV500
Tools Required:
Needle-nose pliers
CAUTION: During this test the unit will not be controlling. It will increment the gas flow from minimum
to maximum over 8 minutes. Be sure to monitor the unit for safe operation.
23. Turn off power. Open electronic drawer. From the front circuit board remove 2-pin jumper from
ACAL (back jumper) using pliers or fingers (see figure -4).
11. Set water flow at about 1.5 gpm (flow is similar to shower flow) 12-15 flashes from green light
between pauses.
12. Turn power ON. Green LED should flash and burner comes on to minimum burn. If red light
flashes there is a problem with the temperature sensors and they must be corrected before