TROUBLESHOOTING GUIDE
780-704/780-705
MODERNIZATION KITS
SEQUENCE OF OPERATION AND SYSTEM CHECKOUT
PROCEDURES
The initial installation portion is now complete and ready for final
system checkout. The checkout procedures listed below must be
followed. While there are redundant safety features built into the
system, it is imperative that you follow the steps outlined below to
ensure proper and safe operation. If you encounter any irregularities,
refer to the
TROUBLESHOOTING GUIDE
1.
❏
Check all wiring connections.
2.
❏
Turn on main gas supply and manual valve on the gas valve.
3.
❏
Turn on electrical power.
4.
❏
Thermostat set high.
5.
❏
Sparking begins, pilot gas ignites.
6.
❏
Pilot flame on sensor, main burner on.
7.
❏
With main burner on, cycle thermostat
off
then
on
.
A. Nonlockout system will turn off and immediately on again.
B. Lockout system will turn off. Sparking will not begin for 5
seconds.
8.
❏
With the main burner on, turn the manual gas valve to
off
position. Wait until all flame is out. Turn manual gas valve
on again.
A. Sparking will begin as soon as the pilot flame is out.
B. Pilot ignition takes place when gas flow is restored.
9.
❏
If this is a lockout system, with main burner on, turn manual gas
valve off. Sparking will begin when the pilot flame goes out. After
60 seconds the system will lockout and sparking will cease.
10.
❏
To restart the system turn thermostat low for 5 seconds. Then set
high again. Sparking will begin in 5 seconds.
11.
❏
It is absolutely necessary that the system be cycled normally
(thermostatically controlled) through at least three complete
heating cycles. Set thermostat to a temperature slightly higher
than the existing ambient. Allow appliance to cycle ON and run
through a normal cycle. Do not manually shorten the cycle.
12.
❏
The initial checkout procedures have been completed. If the
system has functioned normally, return thermostat setting to its
normal setting. The qualified installing agency must completely fill
out and apply the yellow appliance conversion sticker to the front
of the appliance. Leave these and all other instructions with
the homeowner.
TROUBLESHOOTING GUIDE
FLAME RECTIFICATION IGNITION CONTROL UNITS
SP715/SP735
THERE ARE FIVE POTENTIAL PROBLEM CONDITIONS WITH THE
THERMOSTAT SET HIGH:
1. Thermostat on, no spark, no pilot gas.
2. Have spark, no pilot gas flow.
3. Have pilot gas, no spark.
4. Have pilot flame, main burner does not turn on.
5. Short-cycling of main burner. Main burner turns off before the
thermostat is satisfied.
TO PERFORM THE FOLLOWING TEST YOU WILL NEED
A VOLT OHM METER.
PROBLEM #1: Thermostat on, no spark, no pilot gas.
Possible Causes
A No main power
B. Faulty transformer
C. Faulty thermostat
D. Faulty limit
E. Faulty ignition control unit
SOLUTION:
1. With power on and thermostat set high, set your test meter to the
24 volt scale. Probe terminals TH and TR. If you do not read 24 volts,
the problem is not in the ignition system. Perform normal system
checks of main power, transformer, thermostat and the limit control.
If you do read 24 volts at TH and TR the problem is in the ignition
system. Check for loose or defective wiring. If wiring is good replace
the ignition control unit. See your Uni-Line wholesaler for order
numbers.
PROBLEM #2: Have spark, no pilot gas flow.
Possible Causes
A. Main gas supply turned off
B. Manual valve on gas valve turned off
C. Faulty primary valve in the gas valve
D. Faulty wire connection
E. Faulty ignition unit
SOLUTION: Set test meter to 24 volt scale.
1. Be sure main gas valve and manual valve are turned on.
2. With gas on and the system sparking probe terminal TR and the blue
wire terminal on the solenoid on the 7000 gas valve. With 24 volts at
these terminals and pilot gas does not flow, replace the solenoid in
the 7000 gas valve.
3. If you do not read 24 volts at the solenoid valve terminals, probe
terminals PV and MV/PV on the ignition control unit. If you read 24
volts here but not at the gas valve, there is a loose wire connection
in the blue or white wire. Repair the wire connection.
4. If you do not read 24 volts at terminals PV and MV/PV replace the
ignition control unit.
