How do you test a furnace sequencer?

Asked By: Lavinia Percaz | Last Updated: 17th May, 2020
Category: home and garden indoor environmental quality
4.9/5 (241 Views . 11 Votes)
How to Check a Heat Sequencer
  1. Plug the leads into the electric test meter.
  2. Turn off your furnace by shutting off the appliance itself and by shutting off the circuit breaker that powers it.
  3. Touch the probes on the end of the leads to the areas where you just removed the wires on the heat sequencer.
  4. Check the reading on the electric test meter.

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Regarding this, what does a sequencer do on a furnace?

The sequencer is essentially a series of conduits that prevent the voltage from entering the electric furnace from turning on all the heating elements at one time. The heating elements are the electrical coils that warm up as electricity passes through them; they're what actually heats the air.

Similarly, what do the numbers mean on a heat sequencer? Yes, that is a heating sequencer. The numbers mean that contacts M1-M2 close between 1 and 20 seconds after control voltage (24V) is sent to the thermo-disk built into the bottom area of the sequencer.

In respect to this, how do you troubleshoot a heat sequencer?

How to Check a Heat Sequencer

  1. Plug the leads into the electric test meter.
  2. Turn off your furnace by shutting off the appliance itself and by shutting off the circuit breaker that powers it.
  3. Touch the probes on the end of the leads to the areas where you just removed the wires on the heat sequencer.
  4. Check the reading on the electric test meter.

How does a heat sequencer relay work?

Sequencers are basic relays that use a heater coil and a bimetal switch. Control voltage is applied to the heating coils which heats the bimetal switch. The heat causes the bimetal switch to flex, making contact across the switch and sending power to the elements.

29 Related Question Answers Found

Why is my electric furnace not working?

Other electric wiring malfunctions
Loose or corroding wiring and broken relays are among the more common troubles that can cause problems for an electric furnace. The thermostat could lose its connection to the furnace, which can either cause the furnace not to turn on or not to turn off.

How do I turn on my electric furnace?

Turn the furnace back on. On most electric ignition furnaces there is an ignition button, with a smaller red button right next to it. If you're not able to locate this, check your owner's manual for specific instructions. Press on this small button as you press the button for the electric ignition simultaneously.

What does a sequencer do?

A music sequencer (or audio sequencer or simply sequencer) is a device or application software that can record, edit, or play back music, by handling note and performance information in several forms, typically CV/Gate, MIDI, or Open Sound Control (OSC), and possibly audio and automation data for DAWs and plug-ins.

What type of device is inside the sequencer?

A sequencer uses low-voltage electrical energy to warp the bimetal inside it. It then passes power to devices that are in the high-voltage circuit. A contactor uses low-voltage electrical energy to magnetize the solenoid and then pass power to high-voltage devices.

Do all electric furnaces use package sequencers?


Some units may be designed to move enough air across the heating elements so that they do not glow. All electric furnaces use package sequencers.

What does a relay do on a furnace?

The electric relay in a furnace is responsible for relaying electrical power to the heating elements and the blower motor inside the furnace cabinet. The heating elements provide the heat to warm the air, and the blower motor sends this warmed air through the ductwork.

How does a fan sequencer work?

The sequencer does the job of staggering the heating elements so they turn on one at a time, in “sequence.” The sequence does this by acting as a series of circuits that close one at a time, allowing electrical power to move farther down the system to each of the heating elements in turn.

How long does it take an electric furnace to heat up?

With the thermostat set to 'heat', turn up the temperature at the thermostat about five degrees warmer than the current temperature. This should get the furnace to kick on. Now wait about fifteen minutes.

How does a gas furnace work?

A forced-air furnace heats your home through a heating cycle that looks like this: Natural gas or propane is ignited in the burner. The flames heat up a metal heat exchanger and exhaust out of the flue. The furnace's blower forces the heated air into the ductwork and distributes it throughout the home.

What is heat pump system?


Technically, a heat pump is a mechanical-compression cycle refrigeration system that can be reversed to either heat or cool a controlled space. Even in air that seems too cold, heat energy is present. When it's cold outside, a heat pump extracts what outside heat is available and transfers it inside.

How do I reset my furnace?

How to Find My Furnace Motor Reset Button
  1. Turn off the power to the furnace at the circuit breaker. The circuit breaker is clearly marked.
  2. Lift up the blower compartment cover to access the blower wheel and blower motor.
  3. Look for a small red or yellow button on the side of the blower motor.
  4. Press the reset button down if it has popped up.

What is the switch on the furnace?

Beside or near your furnace will be a light switch, this controls the power to your furnace. Sometimes when your furnace does not respond to a request for heat from your thermostat, it is a power issue. First, check to make sure that the switch is in the "On" position.

How long does a furnace control board last?

It seems about 7-10 years has become the norm for expected life cycles in consumer electronic devices, appliances etc.

What happens if I turn my furnace off?


Why Turning Off the Furnace Makes Sense
Even when the furnace is not running, the pilot light burns gas. That adds up to a small amount, but it's still an amount that you have to pay. You can save around $50 or so, depending on the overall amount you pay per unit of natural gas over the course of the summer.

Is the furnace emergency switch supposed to be on or off?

The switch when placed in the OFF position should immediatly shut the furnace down, wether it be oil or gas fired. With the furnace running flip the switch to the off position. If the furnance keeps running the switch wiring is faulty. If that's so, get it fixed.

How much does it cost to replace a circuit board on a furnace?

Furnace Control or Circuit Board Replacement Costs
Replacing a furnace control board costs $200 to $600 or more depending on brand and age.