Service; Troubleshooting - Honeywell MiniZone EMM-3 Product Data

SERVICE

Purge timing— fixed at two and one-half minutes; not field-
adjustable.
Fan operation in Purge mode—fan is on in Purge mode; not
field adjustable.
START
IS 24 VAC
AT R AND C
ON THE EMM
PANEL
?
YES
IS 24 VAC
ON ALL OF THE
ZONES AT R-M1
OR R-C
?
YES
IS THE
THERMOSTAT CALLING
FOR COOL?
YES
YES
CHECK FOR
24 VAC AT Y-M1 OR Y-C
ON THE EMM PANEL. (YOU
SHOULD HAVE
24 VAC.)
YES
IS THERE
CONTINUITY AT R -Y
C
ON THE EQUIPMENT
CONTACTS OF THE
EMM PANEL?
YES
Fig. 7. Thermostat is calling for cooling but the system light is not turning green to show a cool call.
CHECK THE TRANSFORMER
NO
FOR 24 VAC.
THE
THERMAL FUSE
HAS TRIPPED. REMOVE THE
R OR C (TRANSFORMER POWER)
WIRE FROM THE PANEL FOR 15 SECONDS
NO
AND ALLOW THE FUSE TO RESET. TAKE THE
THERMOSTAT AND DAMPER WIRES OFF FROM
EACH ZONE BEFORE YOU RE-ATTACH
THE R OR C WIRE. IS THERE
VOLTAGE AT R-M1 OR R-C
ON ALL OF THE
ZONES?
NO
THERMOSTAT MAY BE IN A 5 MIN DELAY IN COOLING.
MAKE SURE THERMOSTAT IS CALLING FOR COOLING.
DID THE EMM PANEL HAVE ANY CONDENSATION ON IT?
WAS IT STORED IN A COLD PLACE BEFORE BEING
INSTALLED? IF SO, THIS COULD CAUSE THE PANEL TO
MALFUNCTION. LET THE PANEL ADAPT TO THE NEW
CONDITIONS BEFORE POWER UP.
NO
NO
24 VAC AT Y-C ON THE
NO
DO YOU
NO
HAVE A DATS
HOOKED TO THE
PANEL?
THE COOLING EQUIPMENT SHOULD BE ON.
SEEMS LIKE THE PANEL IS WORKING BUT THE SYSTEM
LIGHT IS NOT. REPLACE PANEL.
DATS Operation—High limit is 160° F (71°C); low limit is 44°F
(6°C) and not field-adjustable.

TROUBLESHOOTING

The primary diagnostic tools are the SYSTEM and ZONE
damper status LED and the BOOT and PURGE OVERRIDE
buttons. See Fig. 7 and 8 for troubleshooting flowcharts.
THE PANEL MAY HAVE BEEN DAMAGED.
TAKE THE R OR C WIRE OFF AGAIN FOR 10
MINUTES. AFTER 10 MINUTES, RE-ATTACH
THE R OR C WIRE AND PRESS THE BOOT
BUTTON. CHECK VOLTAGE AT R-M1 OR R-C
ON ALL THE ZONES. IF NO VOLTAGE AT R-M1
OR R-C, REPLACE THE EMM PANEL.
NO
YES
NO
IS THERE JUMPER THE R WIRE TO THE Y WIRE ON THE
THERMOSTAT. IF THE COOL LIGHT COMES ON, YOU
THERMOSTAT? HAVE A BAD THERMOSTAT. REPLACE THERMOSTAT.
YES
IF YOU JUMPER R-Y ON THE THERMOSTAT AND
THE COOL LIGHT DOES NOT COME ON, YOU MAY
HAVE A BAD WIRE. TRY ANOTHER SET OF WIRES
OR CHECK CONTINUITY.
REMOVE ALL WIRES FROM THE PANEL EXCEPT
R AND C (POWER FROM THE TRANSFORMER).
JUMPER R-Y ON ONE OF THE ZONES. IF THE
SYSTEM LIGHT DOES NOT TURN GREEN, REPLACE
THE PANEL.
YES
REMOVE THE DATS WIRES FROM THE BOARD.
RETURN TO "IS THE THERMOSTAT CALLING FOR
COOL" PART OF THE FLOWCHART AND BEGIN
TROUBLESHOOTING FROM THAT POINT.
9
EMM-3 ELECTRONIC MINIZONE™ PANEL
RE-ATTACH EACH ZONE THERMOSTAT WIRE.
ATTACH EACH ZONE SEPARATELY, CHECKING
AFTER EACH ZONE IS ATTACHED IF THE
THERMAL FUSE HAS TRIPPED. AFTER
ATTACHING THE THERMOSTAT WIRES, ATTACH
EACH MOTOR ZONE WIRES, AGAIN CHECKING
THE THERMAL FUSE TO SEE IF IT TRIPS. THIS
STEP-BY-STEP PROCESS SHOULD HELP YOU
IDENTIFY WHAT IS TRIPPING THE THERMAL
FUSE ON THE PANEL.
IT COULD BE A BAD WIRE. IF YOU HAVE
VOLTAGE ON THE PANEL AT Y-C BUT NOT AT
THE THERMOSTAT, THEN IT IS A WIRE. CHECK
FOR VOLTAGE AT R-W, G ON THE THERMOSTAT.
IF THERE IS VOLTAGE, IT IS A BAD Y WIRE.
IF NO VOLTAGE AT R-ANY OTHER TERMINAL
ON THE THERMOSTAT, IT IS A BAD R WIRE.
M13543A
68-3041-2