HVAC Contracting

RSS

This month’s troubleshooting situation involves an up-flow gas furnace that serves as both the heating source in the winter and as the air handler in a split system for cooling in summer. The condensing unit is on a pad next to the building on a concrete slab. Since there is no crawl space or basement, the connecting tubing and wiring for the condensing unit are routed through an underground chase from the equipment room to the outside.

Bob and Tim are on their first service call for winter. They are at a retail store that has 4 units to heat and cool the store. They are all 15 on heat pumps. One area of the store is not heating or cooling well and during the heating cycle, the heat pump auxiliary heat light is staying all for long lengths of time.

If you are primarily a residential technician working on equipment under 5 tons, there is a lot of similarities between the systems you are used to and 5 – 20 ton rooftop units that are common to the light commercial market.

The equipment in this month’s troubleshooting problem is a forced-air electric heating system with five resistance-type elements, and in order to ensure that this equipment can operate with maximum efficiency and prevent an electrical system overload on a call for heat, a multiple-step sequencer system employed.

Modern refrigerant systems are designed to be efficient and leak free. Refrigerant systems are pressurized and, in reality, it is widely accepted that no pressurized system is entirely leak free; it is simply a case of how much and where the system is leaking.

Bob and Tim are at a customer’s house that has a gas furnace and electric air conditioning. The complaint is that the system is not working at all.