No Space Heating; Indoor Temperature Does Not Reach Desired Temperature; No Hot Water (Dhw) - IBC DC Series Installation And Operating Instructions Manual

5.4.5 No Space Heating

POSSIBLE CAUSES
Room thermostat (end switches or zone
controller) / Outdoor sensor faulty.
No voltage (24V DC).
Internal Pump not running.
Burner not firing on space heating: sensor S1 or
S2 faulty.
Burner does not ignite.

5.4.6 Indoor Temperature Does Not Reach Desired Temperature

POSSIBLE CAUSES
Room thermostat setting incorrect.
Water temperature is too low.
Water temperatures are set incorrectly
Pump not running correctly. Pump setting is too
low (variable speed pumps only).
No circulation in the heating system.
No heat transfer as a result of lime scale or
fouling in the heat exchanger.

5.4.7 No Hot Water (DHW)

POSSIBLE CAUSES
Flow sensor not functioning.
No voltage at the flow sensor (5V DC).
Burner not firing on DHW: S3 faulty.
Burner does not ignite.
TROUBLESHOOTING
DC SERIES BOILERS / WATER HEATERS DC 15-95, DC 15-96, DC 20-125, DC 33-160
SOLUTION
•
Room thermostat must be a DRY CONTACT style thermostat
•
Check the wiring.
•
Check and/or Replace the thermostat (end switches or zone controller).
•
Replace the outdoor sensor.
•
Check the wiring against the diagram.
•
Check the connector terminals X4.6 and X4.7 for 24V DC with thermostat
wires disconnected.
•
Check the Fuse.
•
Replace the controller.
•
Check the power supply.
•
Check connector X2.7 and X2.8 for 120VAC while the pump should be
running.
•
Replace faulty pump if 120VAC is present when the pump should be
running.
•
Replace the controller if 120V is not present when the pump should be
running.
Replace sensor S1 or S2. See fault code.
See 5.4.1 Burner Does Not Ignite
SOLUTION
Check the setting and if necessary adjust: Set heat anticipator to 0.1A.
Thermostat must be a DRY CONTACT style thermostat
Increase the space heating water temperature. See Table of Programmable
Parameters in DC / HC Controller Manual. Check outdoor sensor and wiring
for short-circuit.
Target water temperature is set higher than the maximum water
temperature.
Increase pump setting, or replace the pump.
Ensure the zone valves are open and there are no air blockages.
De-scale or flush the heat exchanger on the space heating side.
SOLUTION
•
DHW flow < 2.0 l/min – .5 GPM.
•
Clean or replace the flow sensor.
Check the wiring according to the diagram.
Replace S3.
See 5.4.1 Burner Does Not Ignite
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