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240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
10-17. Freeze protection heaters
Part#
• 319143-531 (EK209)
• 319143-532 (EK210) : Indoor
• 319143-533 (EK211) : Outdoor
• 319143-468 (EK105)
• 319143-535 (EK217)
Unit Part#
#414
#415
#417
#464
Function
Prevents the heat exchanger, water valves, and water pipes within the water
heater from freezing. The heaters are but one of the freeze protection
devices in the water heater.
Failure events
Open circuit failure: Ceramic heaters do not receive the voltage needed to
heat up.
Effects on the water heater
if heater fails
Ceramic heaters do not activate, allowing water contained in the heat
exchanger to freeze up, possibly causing the heat exchanger to burst.
Error codes when heater
fails
N/A
Diagnostic
1. Visual inspection: connection/breakage of wires and the condition of the
heaters.
2. Check: whether those are in the normal range as shown in the following
table.
Color / Number of wires
Black - Black
108 to 132 VAC
(during freeze protection operation)
Checkpoint
B1
The water heater has two types of the heaters in it. The one is for protecting of the heat
exchanger and water pipes, the other one is for protecting of the water inlet and water outlet.
For the water inlet
and outlet
Part# 319143-468 (EK105)
For the heat exchanger
Part# 319143-531 (EK209)
Part# 319143-555 (EK217)
Flat heater
For the secondary heat exchanger
Part# 319143-532 (EK210) : Indoor models
319143-533 (EK211) : Outdoor models