Air Conditioner LogoAir conditioners are all but ubiquitous in the modern developed world, so much so that many people never think about them until their malfunctioning. We simply accept that even the harshest of the summer’s dog days will be pleasant and mild as long as we’re inside. With that being the case, it’s easy to forget just how complex and sophisticated the function of modern air conditioners is – and how important condensate pan float switches are to our summer comfort.

How Air Conditioner Systems Work

Air conditioners work in three stages, facilitated by parts known as the compressor, the condenser, and the evaporator.  First, a special gaseous fluid arrives at the compressor where it is compressed into a dense, higher-temperature fluid. This fluid is then sent to the condenser, which helps dissipate the temperature generated in the compressor and also compress the gaseous fluid into a high-pressure liquid form.

From there, the liquid moves into the evaporator, where its pressure drops and it evaporates back into a gas. Thermal energy is exchanged with the surrounding air, resulting in a cooling effect. The gas finally goes back to the compressor to repeat the cycle, and a fan circulates indoor air so that all of the warm air in a room comes into contact with the evaporator.

The Role of Float Switches

The process described (in a nutshell) above results a slow buildup of liquid condensate, due to the ambient moisture pulled from the air. Air conditioner systems are designed so that the condensate accumulates in a contained drain pan, which empties outside of the system (typically through simple gravity). However algae, dust, and other contaminants can build up and prevent this proper draining.

FS31 Condensat Float SwitchThis is where float switches come in: When a condensate drain pain fails to empty properly, a float switch is often utilized as a high-level alarm, automatically cutting off compressor function before a harmful overflow occurs. In the case of central air conditioning systems, that means sparing homeowners the cost and trouble of fixing water-damaged ceilings, floors, and walls. Or, in larger A/C systems where gravity draining is impractical, a float switch could also be used to activate a condensate pump.

A/C Float Switches from SMD Fluid Controls

SMD Fluid Controls specializes in the design and manufacture of float switches for a huge variety of applications, including those involving HVAC, A/C, and condensate draining. For example, the FS31 vertical float switch made from durable, economical polypropylene and designed especially for condensate drain pans. Whether you need a few units or a few hundred, SMD Fluid Controls can help with off-the-shelf solutions like the FS31 or custom designed solutions to fit specialty needs.


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