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Electric wiring solutions
When troubleshooting, understand you are working with potentially lethal voltages and a highly flammable gas or oil. If you do not have the ability to do these operations safely, do not attempt them.
The instructional videos below cover ways to solve wiring problems found in the HVAC industry.
Sometimes, it is necessary separate the thermostat circuit from the furnace controls. This video shows how to wire the isolation relay.
In the 120v circuit, the Black is the hot lead and it can give you a shock. However, under certain conditions, you can also be shocked by the white wire. The video below covers the conditions under which this can happen.
This video describes the lockout circuit. This circuit is used protect equipment from damage from operating with pressures or temperatures that are too low or high. When a safety switch opens, the lockout relay is energized which opens the control circuit preventing the unit from operating until the power or thermostat is shut off and turned on again.
In the early 1990s new houses were tightened up for air loss. This made some houses too tight and the inside air was not changed often enough. To address this, fresh air damper systems were required.
The system consisted of an outside air pipe with an electric damper installed in the return of the furnace, a relay to start the circulating fan and and exhaust fan. When wiring the damper systems, you must be careful to avoid starting the air conditioner when the fan comes on. The video below shows how to wire this type of system.
The system consisted of an outside air pipe with an electric damper installed in the return of the furnace, a relay to start the circulating fan and and exhaust fan. When wiring the damper systems, you must be careful to avoid starting the air conditioner when the fan comes on. The video below shows how to wire this type of system.