In this month’s troubleshooting situation the equipment that needs servicing is a split system and the refrigerant flow control is handled via an electronic expansion valve (EEV) shown in Figure 1.

In this troubleshooting situation, the equipment is a split system that’s approximately five years old, consisting of a gas furnace to provide heat in the winter, and a condensing unit and “A” coil to provide summer cooling. There are actually three questions to answer in this problem.

In this troubleshooting situation, you are responding to a customer’s complaint about their heat pump, and you’re not the first technician called in to solve this problem of “not keeping the home comfortable and running a lot.”

In this troubleshooting situation you are dealing with equipment that has only been in operation for two months. And during that time frame, the customer has complained that at times the box temperature is higher than it should be, but the unit then seems to recover and freeze OK.

Your role in this troubleshooting situation is a follow-up to visits by other technicians who responded to this customer’s complaint about the cost of operating their heat pump in the winter. Opinions offered so far range from a possibly failing reversing valve to improper use by the customer.

In this month’s troubleshooting situation your customer is requesting a second opinion on a proposed repair to their air-source heat pump. The homeowner originally called for service when they noticed that the house wasn’t cooling down as they would like.

What is the underlying problem with this system, and what do you need to do in order to get it operating properly?

In this troubleshooting situation a technician has responded to a complaint of “not cooling” on a six-year-old R-410A split system that employs an upflow gas furnace indoor air handler and a condensing unit that sits on the ground, and there is less than 20 feet of connecting tubing.

This troubleshooting situation centers around an older 3-ton split comfort cooling system, and the customer is calling because their home is “just not comfortable.” The homeowner also tells the dispatcher that while the unit is operating and air is coming out of the registers, the temperature in the house is too warm.

Jim Johnson, an experienced trade school and community college instructor, discusses the HVAC industry and his column in The NEWS, ‘The Service Ticket.’ Listen now for a hint to the Not Enough Heat question from the Dec. 15 issue.