Re: Listen to Your Aqua Hot
Reply #1 –
MIke,
On the older version of the Aqua Hot Heater (AHE 100 02S and older), the ones with no electronic control board, the number two pump is run by the burner anytime the blower is running. This is done by a red Diode wire from the black burner motor wire on the "C"plug to the number two relay pump power connection.
This connection is energized when the the number two replay is latched by the bathroom thermostat calling for heat. The energized red wire would back feed threw the "C" plug to the Control Unit causing it to fail. The diode prevents this failure.
Good catch or is that good ears for an older fella. Hope this helps.