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I shut off the gas to the unit and the power.i

I shut off the gas to the unit and the power for 1 week. i changed the copper heat exchanger. when i tried to fire the unit the fan comes on but the heater doesn't fire. the service light comes on. a service guy said i need the following, flame sensor replaced, thermal fuse replaced, and no voltage to gas valve. the unit was fine prior to replacing the heat exchanger. does this seem correct all these would go out

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No, that does not seem correct. If all you did was replace the heat exchanger, then tried to start it up, how could everything go wrong. Unless there was another issue with the heater. Not too many people change out the exchanger, unless corrosion has caused a leak there What you CAN try to do is reset the heater. To do this, turn off your heater first-at the toggle switch inside the right hand side door, then turn off the circuit breaker to the heater, wait about 5 to 10 minutes, then reverse the order. Circuit breaker then heater, if you have the digital display, you will see flashing codes, this is the computer resetting, then you should see the normal display. Try starting the heater again. If it still will not fire, let me know if you receive an error code. Also, check to see if the temp the heater is reading is close to that of the actual water temp.

Posted on Jul 01, 2009


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