tekmar 662 Snow Detector & Melting Control - Manual (Page 10)

10
Closing on — % Output Decreasing
After the Opening relay has turned off, the “Closing” light and relay turn
on and the LCD flashes between "CLS" and the current “% Output”. The
time for the device to go from 100% to 0% is set on the “Motor Speed /
Pump Response” dial. During this time, the 4-20 mA, mixing valve or
variable speed pump output should decrease from 100 to 0 %.
% Output
% Output Step Eight Troubleshooting
First observe the system operating parameters. The source of the problem can often be found by noting a temperature or time
reading which seems unreasonable. The indicator lights are also useful in assessing the current state of the control system.
Observing what the control is doing, and understanding the sequence of operation greatly aids in isolating the problem. The next
step is to press the test button and observe the system components working in sequential order. If a fault in a sensor or its wiring
is detected during or after the test sequence, an error message is displayed. The error message look up table provided below
can be used to locate the fault. Once the error is identified, refer to Step Five for testing of the wiring and sensors. After any repair
has been completed, press the Test button to confirm that correct operation has been restored.
Step Nine Before you leave
• Make sure wiring dividers are installed in their proper locations between compartments having different voltages.
• Install the wiring cover over the wiring chamber and secure it to the base with the two screws provided. Place the front cover on
the control and snap it into place. Install a lock if security is required.
• Place this brochure, and all other brochures relating to the installation, in the protective plastic bag supplied with the control. Place
the bag in a conspicuous location near the control for future reference.
• It is important to explain the operation of the control and melting system to all users who may be operating it.
If a fault occurs during normal operation or during the test routine, the LCD flashes back and forth between the word "Err"
and one of the error codes listed.
OUTDOOR SENSOR – OPEN CIRCUIT
Check the Outdoor Sensor and wiring from the terminal plug to the sensor. When
the control has this error, it continues to operate the system assuming an outdoor
temperature of 20
°F (-6.6°C)
OUTDOOR SENSOR – SHORT CIRCUIT
Check the Outdoor Sensor and the wiring from the terminal plug to the sensor. When
the control has this error, it continues to operate the system assuming an outdoor
temperature of 20
°F (-6.6°C)
SUPPLY SENSOR – OPEN CIRCUIT
Check the System Supply Sensor and the wiring from the terminal plug to the
sensor. When the control has this error, the melting system is shut down.
SUPPLY SENSOR - SHORT CIRCUIT
Check the System Supply Sensor and the wiring from the terminal plug to the sensor.
When the control has this error, the melting system is shut down.
SYSTEM RETURN SENSOR - OPEN CIRCUIT
Check the System Return Sensor and the wiring from the terminal plug to the sensor.
When the control has this error, the melting system is shut down.
SYSTEM RETURN SENSOR – SHORT CIRCUIT
Check the System Return Sensor and the wiring from the terminal plug to the sensor.
When the control has this error, the melting system is shut down.
BOILER RETURN SENSOR – OPEN CIRCUIT
Check the Boiler Return Sensor and the wiring from the terminal plug to the sensor.
When the control has this error, the melting system is shut down unless the "Min. Boil
Return" dial is turned off.
BOILER RETURN SENSOR – SHORT CIRCUIT
Check the Boiler Return Sensor and the wiring from the terminal plug to the sensor.
When the control has this error the melting system is shut down.
090 YELLOW SENSOR – OPEN CIRCUIT
Check the 090 yellow temperature sensor (black and yellow wires, terminals 19 &
21), and the wiring from the terminal plug to the sensor. When the control has this
error, the melting system is shut down.
Error Messages
Pump 1 Pump 2
Opening
Boiler
Warning
Closing