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SECTION 11 Operating Details and Troubleshooting
11.A Operating Details
When power is turned on, the digital display will indicate
the boiler outlet temperature. If a demand for heat is
received from a room thermostat or a tank aquastat
(if provided) the third decimal LED, located at the
lower right of the last temperature digit, will illuminate
to indicate that a call for heat has been received and
the startup has been initiated. See Section 9.B for
details. If the LED is not illuminated, that indicates that
the System Startup has not been initiated because all
system parameters are not in their proper operating
range. See Section 11.C and 11.D for details and
corrective procedures.
11.B Electrical Troubleshooting
1. Remove the front cover of the boiler.
2. Verify that 120 VAC is reaching the boiler by
testing at terminals 2 and 5 on TB2.
3. Verify 24 volt transformer output by placing the
meter leads on terminals 1 and 7 on TB1. If
24VAC isn’t present, check the circuit breaker
located next to the transformer. Reset the circuit
breaker if it is tripped. If there still isn't any power
at terminals 1 and 7 on TB1, then remove the
control panel to gain access to the internal control
wiring. Check transformer across the male push
on terminals of the transformer.
4. To perform 24 VAC voltage checks attach one
meter lead to terminal 7 of TB1. Use the other
lead to check for power on any switch on the
boiler.
5. To perform voltage checks on 120VAC attach one
meter lead to either terminal 2 or 3 of TB1. Use
the other lead to check for power at any high
voltage terminal or device.
6. Use Section 9.B on page 36 for greater detail
on how to follow the sequence of operation.
Understanding the control panel's messages will
help to localize the fault.
7. Use Section 7.F Wiring diagrams to follow where
the power should be based on the information
coming from the control panel’s lights.
CAUTION
Label all wires prior to disconnection when
servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper
operation after servicing.
ATTENTION
de mise en garde tous les fils avant le
débranchement lors de l'entretien. Les erreurs de
câblage peut causer le mauvais et dangereux.
Vérifier le fonctionnement correct après l'entretien
WARNING
Follow local regulations with respect to installation
of carbon monoxide (CO) detectors and
manufacturer’s maintenance schedule of the boiler.
AVERTISSEMENT
Conformez-vous aux réglementations locales
pour ce qui est de l'installation de détecteur de
monoxyde de carbone (CO) et du programme de
maintenance du fabricant de la chaudière.
CAUTION
Electrical rework and troubleshooting should only
be done by a qualified HVAC technician.
ATTENTION
Les retouches électriques et le dépannage ne
doivent être effectués que par un technicien
HVAC qualifié.
Temp (F)
Ohms
77
30,000
100
17,300
120
11,200
140
7,400
160
5,000
180
3,500
200
2,400
210
2,100
Table 10. Thermistor Readings
M
INI-
T
HERM
JX
Residential Boilers
®
