We’ve had our heater turned off for a few days, due to nice weather. This morning it got down to 36F degrees outside, and it started to feel chilly inside, so I turned the heater back on.
After about 15 minutes, I heard a really loud bang, and then a weird noise that sort of sounded like the cats trying to get through the barrier to the laundry room door. Except the cats were both upstairs. So I turned on the light and looked, and saw water (or something) running all over around the heater. That was when I turned the whole system off, and after talking it over with my wife, we called an HVAC service company. It took 3 different calls, but someone called me back and said he could take a look – and their company rates are $98/hr. for after-hours service calls.
Sure we can afford it, by taking money away from replacing a window. I just wish that I hadn’t turned it on – because the afternoon high today is supposed to reach 73F degrees.
Vernon Pope 
It would have happened sooner or later though, right?
Oh, absolutely. It was at least 18 years old according to the info we got when we bought this house 4.5 years ago. The sales ad said (at least 18 years old, may be much older, nobody is certain). The HVAC guy we had service the A/C unit outside in 2014 said that the only company in this area to install this specific make of A/C unit was only in business for 2-3 years – back in the early 70’s. If the inside heater/blower were installed by the same company, at the same time, this heater is over 40 years old. I’m no expert, but it does look like a possibility to me.
I’m just glad it was nothing major.
Could have been something “Captain” or perhaps “Sergeant”! lol