What Causes an Overnight Accumulation of Gas in my Solar Collector used as a Swimming Pool Heater?
Question: There is an overnight accumulation of gas in the solar panels that heat my swimming pool. When the solar heating system pump turns on in the morning, a small amount of gas (perhaps a quart) comes out of the discharge line. I suspected a leak in the solar collectors but found none when the water was pumped at about 15 psi. I am concerned that this solar collector gas accumulation may indicate corrosion involving the copper solar collectors and the chemicals in the swimming pool water. Is it possible that this is dissolved gas released overnight, owing to reduced pressure in the solar panels caused by the weight of water trying to return to the swimming pool? – R.H., Lake Charles, LA. Answer: As you suspect, the gas in your collector is quite probably nothing more than air that has come out of solution in the swimming pool water left in the collector overnight. Air developing in the solar collector in this installation would happen for two reasons: The water in the solar panels
