Emerson SMMC-3 manual Troubleshooting Guide, Symptoms Probable Cause Correction

TROUBLESHOOTING GUIDE

SYMPTOMS PROBABLE CAUSE

CORRECTION

System is not operating and system light is not lit.

Display is not lit and power switch is on.

System is not operating, Temperature Standby on display.

Error! – SMTS-1 on display and system not operating.

Error! – SMTS-1 on display after corrections made.

Error! – SMPS-1 on display and system not operating.

No Power to SMMC-3

Supply not energized or power input fuse burned out.

The SMMC-3 is in a standby mode, the ambient temperature outside is above the programmed temperature required to melt snow. There is a communication problem with the temperature sensor

Need to clear SMTS-1 error from SMMC-3 program.

There is a communication problem with the in-ground sensor.

Turn on power using switch on front panel.

Check power supply. If LED above power input terminal connection is not lit, replace fuse (4A spare fuse ) supplied with SMMC-3.

NORMAL OPERATION

Make sure the temperature sensor lead wires are connected to the terminal properly. If the sensor wire has been extended, use 3 Conductor Instrumentation Cable, #18AWG, unshielded, common conductors such as twisted pair communications wire, telephone wire, electrical building wire and doorbell wire is not acceptable. Manufacturer: Belden #5301UE or equal.

Turn off system using the front panel switch, wait 10 seconds and turn on again. The SMMC-3 should now recognize the sensor.

Make sure the in-ground sensor lead wires are connected to the terminal properly. If the sensor wire has been extended, use 4 Conductor Instrumentation Cable, #18AWG, shielded, common conductors such as twisted pair communications wire, telephone wire, electrical building wire and doorbell wire is not acceptable. Manufacturer: Belden #9418 or equal.

The aerial or gutter sensors are wet	Possible communication problem
(covered in snow), the LED above	with the aerial or gutter sensor. No
the corresponding terminal block is	error message will show on the
lit and the system is not heating.	display when this occurs.

The in-ground sensor is wet	The surface of the in-ground sensor
(covered in snow), the sensor	may be dirty, possibly covered with
surface is warm and system is not	sealant.
heating.

Make sure the in-ground sensor lead wires are connected to the terminal properly. If the sensor wire has been extended, use 3 Conductor Instrumentation Cable, #18-20AWG, shielded or unshielded, common conductors such as twisted pair communications wire, telephone wire, electrical building wire and doorbell wire is not acceptable. Manufacturer: Belden #8770 or equal.

Clean the sensor surface to get rid of any contaminant, use mild detergent and carefully scrub with steel wool.

PO. Box 726 n TULSA, OK 74101 n TEL 918-627-5530 n FAX 918-641-7336 n www.nelsonheaters.com

GA-2318, R1

Sheet 12 of 15

May 2008