Question about Hayward H400idl2 400,000 Btu Low Nox Heater Natural Gas

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My service light is on and I have a bO code. The heater will run some times, more time than not it will not run. Thanks Dave

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The bO code is a normal code. It stands for bypass operation and just means that the heater is wired into an automatic controller such as a jandy or aqualogic. If there is a call for heat and the heater doesn't fire, you should be getting an error code. It may take several (3 or so) attempts at firing before you will get the code. HTH

Posted on May 19, 2010


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