Furnace Pressure Switch Stuck Open
Is your furnace pressure switch stuck open? This is a standard furnace problem many homeowners can encounter throughout the years is a pressure switch that becomes stuck in an open position. The reasons behind this issue can vary, and knowing how to tell that your pressure switch is stuck is important for your safety and comfort.
So, if you want to learn more about this issue and how you can go about resolving it, join the team from Oosterveld Heating and Air Conditioning as we outline the ins and outs of gas furnace pressure switches in more detail below.
What is a furnace pressure switch?
The main job of a pressure switch is to keep a close eye on the furnace's air pressure and make sure it stays within the acceptable range, ensuring a safe ignition and combustion process. This safety device can be found in all modern furnaces and is an essential component that ensures your furnace operation remains optimal and safe for you and your family. Here is a closer look at how this part works:
1. Beginning of the Heating Cycle
The furnace blower fan motor turns on when the thermostat registers a demand for heat, forcing air into the combustion chamber.
2. Monitoring Air Pressure
The motor's generated air pressure is sensed by the furnace pressure switch. It checks to see if there is enough air pressure for the gas to ignite and burn safely in order to create heat before it moves to your air vents.
3. Switch Position
The furnace pressure switch closes to complete a power circuit if the air pressure falls within the permissible range. This closure lets the furnace control board know when it's okay to start the burners.
4. Heating and Ignition
The burners are ignited when the control board opens the gas valve, which is made possible by the pressure switch being closed. The heating cycle of the furnace then starts, heating the air that is then distributed throughout the house.
5. Monitoring
The furnace pressure switch keeps an eye on the air pressure during the heating cycle. The pressure switch opens the circuit and turns off the furnace to avoid hazardous circumstances if the pressure ever drops below the permitted range. In other words, it ensures that furnace combustion gases to not build up and lead to issues like carbon monoxide leaks and exposure to other harmful gases.
Why is my pressure switch stuck open?
Pressure switch problems come in various forms. And in all honesty, there are numerous features why you have a pressure switch stuck open. Knowing why your furnace pressure switch remains open can aid homeowners in identifying this type of issue quickly, and get their HVAC system back up and working correctly. The following are some typical causes of a pressure switch that is stuck open:
Blocked Vent or Exhaust Pipe
When airflow is impeded by obstructions in the vent or exhaust pipe, it generates insufficient pressure to keep the pressure switch open.
Malfunctioning Motor
Insufficient air pressure due to a malfunctioning or slow-acting motor is also possible.
Blocked Condensate Drain
A clogged condensate drain may cause the safety feature of the pressure switch to remain open.
Defective Pressure Switch
The pressure switch may remain open even under the right circumstances due to wear and tear or internal issues that produce inaccurate pressure measurements.
Seeking advice from a certified HVAC specialist is recommended in order to fix a pressure switch that is jammed open. They can conduct a comprehensive examination, pinpoint the underlying cause of the problem, and carry out the required repairs or adjustments needed to get your furnace back up and running correctly in no time.
What causes pressure switch lockout?
When the pressure switch in a furnace keeps failing to close during the ignition sequence, a safety mechanism known as a pressure switch lockout takes place. The furnace is unable to operate in a potentially hazardous manner while it is locked out. A pressure switch lockout can be caused by a number of things, including:
- A clogged air filter, blocked ducts, or closed vents.
- Obstructed vents or exhaust pipes.
- Malfunctions or incorrect speed of the motor.
- A clogged condensate drain.
- Wear, tear, or electrical issues connected to the pressure switch. There could also be tripped circuits in your breaker box.
- Damaged or kinked tubing affects pressure readings.
- Problems with the gas valve.
- Dirty or malfunctioning flame sensors.
- Even in situations where the air pressure is appropriate, a pressure switch that is set to the wrong threshold may not close.
An experienced HVAC technician needs to perform an in-depth inspection and troubleshooting in order to determine the precise reason for the pressure switch lockout that is keeping your furnace pressure switch stuck open. Frequent maintenance can help avoid problems that result in lockouts, such as cleaning parts and changing filters.
How do I check my furnace pressure switch?
For safety reasons, homeowners are highly discouraged from trying to inspect or troubleshoot the pressure switch on their own. Unqualified personnel handling furnace components face a risk of causing harm to themselves or the equipment itself.
Contacting a licensed HVAC repair specialist as soon as possible is strongly advised. These experts have the experience and knowledge needed to safely inspect if the pressure switch is stuck open and other vital furnace components. Seeking professional help will prolong the life and dependability of your heating system and guarantee a precise diagnosis and resolution of any problems. Setting aside time for the experience of a trained technician is a proactive way to keep your home cozy and safe throughout the wintertime.
Common signs that indicate your pressure switch is stuck open and in a lockout mode include:
- A furnace that won’t ignite.
- The inability of your furnace to produce heat.
- A furnace that is short cycling.
- Clicking noises coming from your furnace as it operates
- An error code may be displayed on your thermostat.
Do any of these signs look familiar? If so, the pressure switch on your furnace may be malfunctioning. Luckily, the certified HVAC team at Oosterveld Heating and Air Conditioning is here to help resolve the issue swiftly.
Problems with your gas furnace pressure switch? Contact Oosterveld today!
Our certified HVAC technicians are available for all repair and maintenance services 24/7/365 days a year, including after-hours, weekends, and holidays, at no extra costs. Furthermore, in cases of emergencies, we are also available for same-day repair appointments.
Oosterveld Heating and Air Conditioning proudly operates throughout Acton, Cambridge, Fergus, Puslinch, Belwood, Elora, Guelph, and Rockwood.
To work with us, don't hesitate to book a service call directly with a team member over the phone or use our online scheduling form. With the help of Oosterveld, we'll get your furnace back up and working properly in no time!
We look forward to getting your home's furnace functioning properly quickly!
