How to Tell If AC Pressure Switch Is Bad: A Guide for Sheboygan Residents

Professional Services
May 10, 2024

Sheboygan has chilly to icy weather most of the year, the highs from December to February rarely transcending freezing point. The summers are milder, with warm days touching 80-degree max, but just as you need your furnace during the winter, you’ll need an AC unit to have your back in the warmer months. In this post, we’ll show you how to tell if an AC pressure switch is bad. 


A faulty switch is not as easy to fix as dirty air filters or frozen coils. So, rather than brave a DIY project, trust a licensed AC repair technician in Sheboygan for assistance. Below, our specialized team breaks down what a pressure switch does and common symptoms that demand repairs. 


What Does an AC Pressure Switch Do?

Your cooling system depends on refrigerant so it can suck in the warm surrounding air and drop its temperature before rereleasing it into your space. That means having too much or not having enough coolant drastically alters your AC unit's functioning ability. But since your HVAC unit resembles a system of checks and balances, with one part always monitoring another, this is where AC pressure switches come in.


Each unit has two switches: the low-pressure switch that pinpoints when refrigerant levels drop too low (like during leaks), and the high-pressure switch that observes blockages that raise the pressure. For the latter, the issue doesn’t have to be with the refrigerant itself, but if the coils that the Freon travels within accumulate dirt or blockages, it won’t release heat from the refrigerant, keeping its pressure high. 


Signs of Bad AC Pressure Switches in Sheboygan 

If your pressure switch is working optimally, your Sheboygan unit will keep functioning. Below are some symptoms of faulty pressure switches that could affect functionality. 


Your Pressure Switch Is Constantly Turning Off Your Sheboygan Unit

Because the switches act as safety sensors while overseeing your unit, they shut down if they notice anything unusual in the refrigerant levels to protect your unit and family. For instance, pumping low-pressure refrigerant into the compressor damages it and requires costly repairs just as high-pressure causes dangerous explosions and unit replacements. 


However, if one or both are defective, they’ll power down your unit, even if the refrigerant levels are fine. In some cases, it’ll turn off and stay off, but other times, it’ll short cycle, which causes compressor wear, higher cooling costs, and lower energy efficiency


Warm Air Is Coming Out of Your Unit’s Vents

Another way how to tell if an AC pressure switch is bad in Sheboygan is if the air doesn’t seem to be cooling. Your “controlled air” may rerelease through vents or air ducts with the same heat and humidity as before because of incorrect refrigerant pressures. But first, let’s look at how it should work.


Air enters your unit via vents and travels over the evaporator coil that has liquid coolant running within. As the chemical solution absorbs the heat from the surrounding air, it expands and turns into a high-pressure gas that must travel to the outdoor unit to expel the heat outside your home and return to a low-pressure liquid. But how can this help you when identifying bad pressure switches?


Maybe dirty coils are creating a barrier between the air and refrigerant (which restricts heat flow), or a refrigerant leak is reducing the available amount in the system. If your switches aren’t aware of these issues, they’ll refuse to shut down your cooling system despite the coolant’s struggle with heat absorption. Therefore, heat can reenter your Sheboygan home. 


Detecting Faulty AC Pressure Switches with Unusual Noises

As we’ve said before, your compressor turns on and off with inadequate refrigerant pressure. Because this component clicks when powering up or shutting down, ceaseless clicking throughout your cooling cycle may occur. 


Humming or vibrating sounds also develop in the outdoor condenser compartment if the switches’ contact points corrode or undergo blockages. Just like in the above cases, an AC pressure switch diagnosis is crucial to uncover that the root cause is indeed the pressure switch so the technician can accurately remedy them. 


It Doesn’t Get More Professional Than Our #1 Sheboygan HVAC Team!

For over 30 years, our locally-owned and operated business has put knowledgeable solutions and high-quality work at our forefront. So, whether you want to know “How many hours should an AC run?” or how to tell if an AC pressure switch is bad, contact us 24/7. Professional Services also helps with troubleshooting AC pressure switches and more, so call 262-268-9767!

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