How to identify and repair restrictions and damage in the liquid line
March 6, 2017
In last month’s article, “Inside Filter Driers,” which appeared on Page 18 of the Feb. 6 issue of The NEWS, we covered the internal construction, filtering, and drying materials within a refrigerant filter drier. This month, we’ll deal with troubleshooting, service, and replacement of the filter drier.
Bob and Tim were on their way to a no heating call. When they arrived, they looked at the house and saw that it had a package unit. They talked to the housewife and she told them that the unit stopped running sometime in the middle of the night last night.
Bob and Tim were checking a customer's air conditioner and initially thought the unit must be out of refrigerant or very low on refrigerant. But after adding some refrigerant, the suction pressure did not rise at all. Bob then determined they should look for restrictions in the liquid line or the suction line.
Bob and Tim were at a customer’s house doing a seasonal checkup on a condensing gas furnace. This was routine service carried out every year on this customer’s equipment per a service agreement. But when they tried to operate the furnace, the burner would not light.
In this month’s troubleshooting situation, you’re responding to a customer’s complaint that his furnace isn’t heating properly. The equipment is an 80 percent AFUE, natural gas, induced draft unit that employs a hot surface ignition system.
A customer was explaining what was going on with his air conditioning system. His old system had stopped working and he was told that it needed to be replaced. Money was tight and a cousin had a system removed from a rental property. So they replaced the original 3-ton package unit with a 4-ton package unit.
Bob and Tim had just arrived at a service call, the first one for the day. The complaint was that the homeowner’s air conditioning had stopped sometime in the night and the residence was hot. After their initial checks, they suspected a low charge.
The equipment in this troubleshooting situation is a package unit heat pump and the customer’s complaint is that the unit is “blowing warm air.” When you respond to this service call, you confirm that the indoor temperature is near 90°F, and you also find that the customer has turned the equipment off while awaiting your arrival.
Bob and Tim were on their last service call for the day. It was an apartment house with a heat pump and the weather was warm during the day and cool at night. The tenant had just moved into this apartment and was trying to get the air conditioning to operate to her satisfaction and she said it was too breezy.
Bob and Tim were at the house of a customer who said that her air conditioning unit did not cool well in the hot weather three days ago. She said the unit actually froze up and had ice on the outdoor portion of the unit on the big line. She shut the unit off and called for service.