#coil

Tech Tips:

Every contractor is different. I get that. We don't all need to do everything the same way or include the same services with repairs, but there are some “best practices” that can save you a lot of heartache before, during, and after you make a big repair. Catch it During Diagnosis Let's say you […]

Checking Evaporators on Furnaces

In Florida, there are not many gas furnaces—at least not as many as up north. Sometimes, we can look like real dummies compared to techs who work on them every day. One thing to know about 80% gas furnaces with cased evaporator coils is that you can often check the evaporator coil by removing the […]

Stacking Evaporator Coil Stages

In commercial HVAC, you will find several different types of multi-stage evaporator coils: intertwined (shown above), horizontal face split (one coil on top of another), and vertical (side by side). When staging a horizontal evaporator, pay attention to ensure that stage #1 is on the bottom and stage #2 is on the top. If stage […]

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In this short podcast episode, Bryan talks about crankcase heaters, including their different types, what they do, and when we need to use them.

Crankcase heaters usually come in belly band varieties, but some can be inserted into the sump of the compressor. As their name suggests, crankcase heaters heat the crankcase when the compressor is off. They prevent flooded starts since the heat keeps refrigerant from condensing to a liquid in the compressor when the system isn’t running.

Long off times, long line sets, and cold temperatures all increase a system’s risk of flooded starts. Hard shutoff TXVs, liquid line solenoid valves, and crankcase heaters are all ways to reduce these risks; the valves hold liquid refrigerant back, and crankcase heaters merely prevent refrigerant from condensing.

Crankcase heaters have to be wired to the line side of the contactor or starter. They’re often wired around one of the contacts (with a single-pole contactor). When the contact opens, there is a circuit from one leg, through the crankcase heater and compressor windings, to the other leg. This method does NOT use the compressor winding itself as a crankcase heater. When you use a crankcase heater on a compressor with a seam, you want the part of the heater that does the tensioning near the seam. Crankcase heaters should be installed at the base of the compressor, and you’ll usually use OEM crankcase heaters.

“Crankcase Heaters and Single-Pole Contactors” tech tip: https://www.hvacrschool.com/crankcase-heaters-and-single-pole-contactors/

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Crankcase Heaters – Short #248

07/08/2025

Bryan Orr

The Contactor Reimagined w/ Copeland

07/03/2025