7800 SERIES EC7890A,B/RM7890A,B RELAY MODULE
65-0204–1
19
Equipment Recommended
1
Voltmeter (1M ohm/volt minimum sensitivity) set on the
0-300 Vac scale.
2
Two jumper wires of insulated no. 14 wire, 12 inches
(304.8 mm) long, with insulated alligator clips at both
ends.
General Instructions
A
Perform all applicable tests listed in Table 4 in the
order listed.
B
MAKE SURE THAT ALL MANUAL FUEL SHUTOFF
VALVE(S) ARE CLOSED.
C
Perform only those tests designated for the specific
7890 model being tested.
D
Raise the setpoint of the operating controller to
simulate a
call for heat.
E
For each test, open the master switch and install the
jumper wire(s) between the subbase wiring terminals
listed in the Test Jumpers column of Table 4.
F
Close the master switch before observing operation.
G
Read the voltage between the subbase wiring terminals
listed in the Voltmeter column of Table 4.
H
If there is no voltage or the operation is abnormal,
check the circuits and external devices as described in
the last column.
I
Check all wiring for correct connections, tight terminal
screws, correct wire, and proper wiring techniques.
Replace all damaged or incorrectly sized wires.
J
Replace faulty controllers, limits, interlocks,
actuators, valves, transformers, motors and other
devices as required.
K
Obtain normal operation for each required test before
continuing the checkout.
L
After completing each test, be sure to remove the test
jumper(s).
WARNING
Make sure all manual fuel shutoff valves are closed.
MPORTANT
Low fuel pressure limits, if used, can be open.
Bypass them with jumpers for the remaining Static
tests (if required).
Table 4. Static Checkout.
Test
No.
7890
Models
Test
Jumpers
Voltmeter
Normal Operation
If Operation Is Abnormal,
Check the Items Listed Below
1
All
None
3-L2
Line voltage at terminal 3.
1. Master switch.
2. Power connected to the master switch.
3. Overload protection (fuse, circuit
breaker) has not opened the power line.
2
All
None
6-L2
Line voltage at terminal 6.
1. Limits.
2. Burner controller.
3
All
3-10
—
Ignition spark (if ignition
transformer is connected to
terminal 10).
1. Watch for spark or listen for buzz.
a. Ignition electrodes are clean.
b. Ignition transformer is okay.
4
All
3-8
—
1. Ignition spark (if ignition
transformer is connected to
terminal 8).
2. Automatic pilot valve opens (if
connected to terminal 8).
NOTE: Refer to wiring diagram
of system being tested.
1. Watch for spark or listen for buzz.
a. Ignition electrodes are clean.
b. Ignition transformer is okay.
2. Listen for click or feel head of valve for
activation.
a. Actuator if used.
b. Pilot valve.
5
All
3-9
—
Automatic fuel valve(s) opens. If
using direct spark ignition, check
the first stage fuel valve(s)
instead of the pilot valve.
Same as test no. 5. If using direct spark
ignition, check the first stage fuel valve(s)
instead of the pilot valve.
6
All
3-4
—
Alarm (if used) turns on.
1. Alarm
Final
All
CAUTION
After completing these tests, open the master switch and remove all
test jumpers from the
subbase terminals. Also remove bypass jumpers from the low fuel pressure limits (if used).