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240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
5. Schematic diagram
dŚĞĚŝĂŐƌĂŵďĞůŽǁƌĞĨĞƌƐƚŽďŽƚŚƚŚĞŝƌĞĐƚsĞŶƚ/ŶĚŽŽƌŵŽĚĞůƐĂŶĚKƵƚĚŽŽƌŵŽĚĞůƐ͘
1. When a hot water tap is opened, cold water enters the water heater.
Ϯ͘dŚĞǁĂƚĞƌĨůŽǁƐĞŶƐŽƌĚĞƚĞĐƚƐƚŚŝƐǁĂƚĞƌĨůŽǁĂŶĚƐĞŶĚƐƚŚŝƐŝŶĨŽƌŵĂƚŝŽŶƚŽĐŽŵƉƵƚĞƌ͘
ϯ͘dŚĞĐŽŵƉƵƚĞƌŝŶŝƚŝĂƚĞƐĨĂŶŵŽƚŽƌĂŶĚƐĞŶĚƐƐŝŐŶĂůƚŽŝŐŶŝƚĞƌƚŽĐƌĞĂƚĞŝŐŶŝƚŝŽŶƐƉĂƌŬ͘
4. The main, proportional, and solenoid gas valves open to allow gas input.
ϱ͘dŚĞŐĂƐŝŐŶŝƚĞƐĂŶĚĨůĂŵĞƐĂƉƉĞĂƌŝŶƐŝĚĞƚŚĞďƵƌŶĞƌĐŚĂŵďĞƌ͘
ϲ͘tĂƚĞƌĐŝƌĐƵůĂƚĞƐƚŚƌŽƵŐŚƚŚĞŚĞĂƚĞdžĐŚĂŶŐĞƌĂŶĚŝƐŚĞĂƚĞĚƵƉƚŽƚŚĞƐĞƚƚĞŵƉĞƌĂƚƵƌĞ͘
ϳ͘hƐŝŶŐƚŚĞƌŵŝƐƚŽƌƐƚŽŵĞĂƐƵƌĞƚĞŵƉĞƌĂƚƵƌĞƐ͕ƚŚĞĐŽŵƉƵƚĞƌŵŽĚƵůĂƚĞƐƚŚĞŐĂƐĂŶĚǁĂƚĞƌǀĂůǀĞƐƚŽ
ensure proper output water temperatures.
8. When the tap is closed, the water heater shuts down.
dŚĞŝƌĞĐƚsĞŶƚ/ŶĚŽŽƌŵŽĚĞůƐĚĞƚĞĐƚƐƚŚĞĞdžŚĂƵƐƚƚĞŵƉĞƌĂƚƵƌĞďLJƵƐŝŶŐ
ĞdžŚĂƵƐƚƚŚĞƌŵŝƐƚŽƌĂŶĚŚŝͲůŝŵŝƚƐǁŝƚĐŚĨŽƌĞdžŚĂƵƐƚĚƵƌŝŶŐƉƌŽĐĞĚƵƌĞƐŽĨϯƚŽϴ͘
NOTICE
HO
T
C
OLD
GAS
Hi-limit switch
Inlet drain
ƉůƵŐĮůƚĞƌ
Outlet thermistor
Drain plug
Main gas valve
Gas solenoid valve 2
&ĂŶŵŽƚŽƌĨŽƌĐŽŵďƵƐƟŽŶ
Igniter
O.H.C.F
Flow adjustment valve
with Flow sensor
'ĂƐƉƌŽƉŽƌƟŽŶĂůǀĂůǀĞ
Gas solenoid valve 1
Gas solenoid valve 3
Heat exchanger thermistor
Inlet thermistor
Exhaust thermistor
Intake port
120
Exhaust
Secondary heat exchanger
Primary heat exchanger
Hi-limit switch for exhaust
540 (T-H3) models only
Drain pan
Condensate drain
PCB
ON-OFF-switch for power supply
Surge box
Bypass valve
Direct Vent Indoor models only
Flame rod
Igniter rod
ŝƌͲĨƵĞůƌĂƟŽƌŽĚ
Heater
VAC