Re: Central AC and Water Heater
It appears your home is going into negative pressure when the A/C is running.
There is not enough air within the area of the hot water heater to main enough upward draft in the fluse during combustion.
Is the A/C part of a forced air furnace that located by the water heater?
Is the water heater and air handler in an enclosed room?
You should call an HVAC professional to come out and evaluate what's causing the negative pressure that creates backdrafting of your gas water heater.
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