Midco DS45B - Manual (Page 11)

Maintenance Continued
LIGHTING INSTRUCTIONS:
1. SET OPERATING CONTROL TO OFF OR THERMOSTAT BELOW ROOM
TEMPERATURE.
2. TURN MANUAL GAS COCK KNOB ON COMBINATION VALVE TO ON
3. TURN BURNER POWER ON.
4. SET OPERATING CONTROL TO ON OR THERMOSTAT TO CALL FOR HEAT.
5. WAIT 6 SECONDS. IF BURNER HAS FAILED TO LIGHT, OR IF BURNER LIGHTS
THEN GOES OUT AND SYSTEM GOES INTO SAFETY LOCKOUT, DE-ENERGIZE
THE SYSTEM BY SETTING OPERATING CONTROL TO OFF OR THERMOSTAT
BELOW ROOM TEMPERATURE FOR AT LEAST 30 SECONDS TO RESET THE
SYSTEM AND THEN SET OPERATING CONTROL TO ON OR THERMOSTAT TO
CALL FOR HEAT.
TO SHUT OFF
1. TURN MANUAL GAS COCK KNOB ON COMBINATION VALVE TO OFF.
2. TURN BURNER POWER OFF.
SHOULD OVERHEATING OF THE GAS UTILIZATION EQUIPMENT OCCUR:
1. Shut off the Main Manual Shut-off Valve to the equipment.
2. Do not shut off the power switch to the ECONOMITE burner, or to the equipment pump
or blower.
WARNING: If PROPANE gas is used and the burner is located in a basement,
crawl space or confining space, contact your gas supplier about installing a GAS LEAK
warning device. PROPANE gas is heavier than air and can settle in low areas or con-
fined spaces. This would create a danger of explosion or fire. If you suspect a gas
leak, follow instructions on front of this manual.
Make sure the thermostat and operating controls are calling for heat. Defective wiring or loose
connections can simulate the component defects outlined below. Check associated wiring
before replacing a component.
ELECTRICAL AND FLAME CHECKS MUST BE MADE IN THE ORDER LISTED.
I. MOTOR WILL NOT RUN OR MOTOR RUNS IN REPEATED CYCLES.
A. Confirm 120V between strip terminals 1 and 2 and verify the circuit polarity and
electrical ground, between strip terminal 1 and GND.
B. Check 24V* operating control circuit:
1. Between left strip terminal T and GND.
a. No voltage, transformer defective
b. Very low voltage,* circuit overloaded or transformer defective.
2. Between right strip terminal T and GND. No voltage, circuit between T and T is open.
C. Confirm 120V between strip terminal 2 and motor relay terminal 4:
1. No voltage, motor relay is defective.
2. Voltage present, motor is defective.
II. MOTOR RUNS CONTINUOUSLY, BUT NO FLAME.
A. Confirm that both Main Manual Shut-Off and Combination Gas Shut-Off valves are in
the ON position.
B. Whenever the burner fails to light during the 6-second ignition try, or if the flame is
lost during the burner run and not re-established within 6 seconds, the Electronic
Control will shut off the combination valve and lock out. To reset the Control for
restart, set the operating control to OFF or thermostat below room temperature
for at least 30 seconds.
1. Check for 24V* between the Interlock Switch NC terminal and strip terminal GND.
No voltage, blower interlock circuit is defective. See Section X.
2. If Electronic Control has a fuse, test for 24V* from each end of fuse to strip
terminal GND.
C. For each of the following tests, reset the Electronic Control per step II.B. TESTS
ARE VALID ONLY DURING THE 6 SECOND TRIAL FOR IGNITION.
1. TURN THE MANUAL GAS COCK VALVE OFF. Check for 24V* between the
Electronic Control VALVE terminal and strip terminal GND. No voltage,
defective Electronic Control.
Consumer Instructions
11
Trouble Chart
Trouble Chart
Consumer Instruction
Continued