Rinnai 37AHA04508KA5 Installation, Operation And Maintenance Manual page 23

Installation
CHECK TRANSFORMER FOR
CORRECT VOLTAGES
PRI:VAC = 115V +/-
SEC: VAC = 24V +/ -
YES
CHECK 3 AMP
FUSE; IS FUSE
INTACT
YES
CHECK T'STAT FOR CONTINUITY
WITH OHM METER BETWEEN
'R' AND 'W'
CHECK FOR 24 V ACROSS
'WH/FS' PINS
VAC = 24V +/-
YES
CONTACT TECH. SUPPORT
If a condensing unit and cased coil set is used in conjunction with the Rinnai Air Handler for cooling,
refer to air conditioning manufacturer's instructions for hook-up and troubleshooting details.
Figure 23:
24V Troubleshooting - Flow Sensor (FS) Configuration
START
WITH DOOR SWITCH CLOSED
(SET SYSTEM IN HEATING
MODE -CALL FOR HEAT)
YES
IS 'LED' ON
NO
(1) CHECK FOR WIRING PROBLEM(S)
(2) CHECK TRANSFORMER; IF DEFECTIVE,
REPLACE FAULTY COMPONENT
NO
(1) CHECK FOR WIRING PROBLEM(S)
(2) CHECK FUSE; IF DEFECTIVE,
REPLACE FAULTY COMPONENT
IS THERE
CONTINUITYAT
T'STAT
YES
CHECK FOR WIRING
PROBLEM(S) AND REPAIR OR
REPLACE AND RETURN TO
START
NO
CHECK PCB; IF DEFECTIVE
REPLACE COMPONENT AND
RETURN TO START
NO
SYSTEM
WORKING
FINISH
Rinnai Corporation Hydronic Air Handler Manual
NO
GO TO AIR HANDLER START UP
AND 'LED' TROUBLESHOOTING
24V BETWEEN THERMOSTAT AND PCB
NO
ENSURE THAT T'STAT IS IN
HEATING MODE AND RECHECK
FOR CONTINUITY
YES
IS THERE
CONTINUITYAT
T'STAT
NO
CHECK THERMOSTAT; IF
DEFECTIVE REPLACE
COMPONENT
YES
24V BETWEEN CONDENSING UNIT AND PCB
23