Several years ago, I found that my pressure canner would drop in pressure, sometimes significantly, while in the middle of a canning session. I thought maybe I had a bad burner or a bad thermostat on the burner. I replaced my canning burner, but I still had the same problem – the canner would drop in pressure during a canning session.
Then I realized that the pressure drop would happen every time my air conditioner would turn on. Vents blew on my stovetop at both ends of the island it was on and blew onto the canner, cooling it off. The solution? Block the flow of air onto the canner. I use C-clamps and clamp towels to the overhead vent hood on either end of the island. Works perfectly. No more pressure drops during canning. And I still benefit from the air conditioning in the kitchen.
