Things That Go Boom in the Night

Night before last I was awakened at about 6AM by a loud boom. It even shook the house a bit. I thought maybe a large trash container was being delivered at the construction site across the street. But upon inspection I noticed no activity at the site. I paid it no more attention and went back to sleep.

Later in the day I took my daily swim. I keep my pool covered except during the swim. This keeps the heat in and saves big-time on gas costs. While swimming I heard another loud boom. It sounded like it came from my neighbors back yard. I popped up from the water and peered through the fence and saw nothing and finished my swim. The way I have things set up there is a timer that comes on at 6AM in the morning, starts the pump and this fires up the heater. By swim time midday the pool is up to temp, the heater cuts off and I can take a comfortable swim. Occasionally during the swim the heater will kick back in again.

After the swim, as I always do, went outside my fence to where my pool heater is to turn it off along with the pump. That is when I saw the front panel of the heater lying on the ground a foot or so from the heater. I put 2 and 2 together and the picture became clear. My pool heater was essentially "blowing up" every time it started. It is an old heater which I recently had repaired but I knew it was not long for this world. Apparently some safety device had failed which allowed a large buildup of gas inside the heater before the electronic pilot actually ignited. Science 101: flammable gas + air + spark = BOOM!

The weird thing is that even after the explosion the heater stayed lit and heated the pool water. I called my pool guy right away and told him to get me prices on a new heater. I did not know how many more cycles of "boom+heat" the old heater was good for and did not want to find out.