Vulcan-Hart 3-130, Service Manual

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5 – 3
5.5 ERROR CODES
ERR 1 MUFFLE OVER TEMPERATURE
The controller monitored a temperature above
°C. This could mean a faulty thermocouple (mV
reading too high) or an erratic thermocouple
performance (the temperature readout is not
stable at elevated temperatures).
ERR 2 OPEN TC DETECTED
To check for open TC, turn power to furnace off
and short TC input terminals. Turn power back
on. If ERR 2 disappears, then replace TC.
Possible solutions:
Change PCB if problem persists.
ERR 3 TMAX OVER TEMP
The controller monitored a temperature above
Tmax + 20°C. This could mean:
* The Tmax was set up too low for this program
* The destination temperature is relatively low
compared to the programmed heat rate, eg.
too much temperature overshoot.
ERR 8 EEPROM READ/WRITE ERROR
(APPLIES TO 9493980 ONLY)
Program parameters entered during the idle
mode are transferred and stored in a 16K-bit
Electrically Erasable Programmable Read Only
Memory (EEPROM) device. The serial data on
U10 is monitored and any abnormal behavior
from the devices’ specs is answered with an
error code. Press ENTER and check:
* Data, Clock train on U10-5,6
* Replace device
ERR 19 NO LINE FREQUENCY DETECTED
(APPLIES TO 9493980 ONLY)
* Check U1 A-1, 100 or 120 Hz pulse train
* Remove Power
SECTION 5 - TROUBLESHOOTING - 3-STAGE