Proving flame is an important part of the gas firing sequence. Without proof of flame, you risk dumping unspent gas into the heat exchanger, resulting in an explosion. There are many ways to “prove flame,” but we are focusing on the flame sensing rod (flame rectification) method here. Here are the facts: Flame sensing rods, […]

I didn't install this unit. First off, attic installations are among my least favorite applications from the standpoints of serviceability, system longevity, and a laundry list of other items. Here in Florida, it's just a bad idea due to the high humidity and temperature in a vented attic and the condensation issues that can and […]

The chart above is from a Carrier heat pump, and it lists some common accessories. I have heard this common pressure switch (last on the list) called a low-pressure switch (because it opens on fall in pressure) and a high-pressure switch (because it's in the liquid line), but RARELY do I hear it called its […]