Technical Tips

Part 1 and part 2 of this series covered defrost diagnostics and electrical testing. You’ve checked voltage, tested resistance, and listened for clicks on a heat pump’s reversing valve. If the valve still isn’t working properly, it’s time to examine the mechanical side and check for internal leaks.

Safety shutdowns in gas furnaces are meant to protect homeowners, equipment, and technicians. Yet every heating season, contractors across the country lose money, time, and customer trust because safety faults are misdiagnosed as failed components instead of the warning signs they truly are.

When it comes to heat pumps, few topics stir as much debate as inverter compressors.

As we head into the colder months, HVACR technicians need to understand the fundamentals of defrost control board operation. While there are many types of defrost control boards on the market, they all function similarly. Let’s break down the basics so you’re prepared to handle this common cold-weather issue.

Skipping the manufacturer’s instructions during installation may result in a furnace that fails within six months or less. For example, heat exchangers can crack from improper venting, and gas valves can clog and malfunction by skipping essential piping steps. This happens all the time when installers rush through jobs.

Part 1 in this series covered defrost cycle problems in heat pumps. Now, let’s discuss the second major winter issue: heat pumps stuck in one mode.

Your phone rings at 7:00 AM in January. The homeowner says their heat pump quit, and the house is freezing. When you pull up, there’s ice everywhere on the outdoor unit — a solid block covering the whole thing.