What is a freeze stat used for?

What is a freeze stat used for?

A freezestat is a low-ambient-temperature-limit control device. It is the standard control used to achieve water-coil low-temperature protection. If air temperature at a coil drops to just above freezing, a freezestat changes over its contacts and initiates protective action.

How do you trip a freeze stat?

The freezestat will “trip” if any section of the temperature sensor element drops below the setpoint. The sensor element can be various lengths, often up to 20ft long,, and will trip if any 12” to 18” length goes below the setpoint.

How does a freeze switch work?

When the temperature reaches a specific setpoint, the pressure in the diaphragm will trip a switch which typically shuts down the flow of outside air while the capillary bulb’s temperature is at or below the setpoint.

How does AC freeze sensor work?

The thermistor is a temperature sensor that sends signals to the control board. One end is conected to the evaporator coil, the other to the control board. If the thermistor senses the evaporator coils are freezing over during operation, the control board will shut off the air conditioner.

What is the most vulnerable portion of a water coil to freezing?

The answer is fairly simple and consists of two main factors: The circuitry of the coil where the pressure builds, and the weakest point in that circuit. Extensive testing has shown that the failure will appear as a bloated area in the tube header or bend that has expanded.

Where should a freeze stat be located?

Normally the freeze stat goes on the leaving face of the heating coil set at 38F. Sometimes with a hot water coil there will be a small freeze protection pump as part of the piping system to rat race water around at the coil to keep it from freezing in the event of a heating plant failure.

What connects the outdoor heat pump unit to the indoor air handler?

Line set – This is a tubing made of copper. It connects the air handler to the outdoor unit and carries the refrigerant.

Where is a freeze stat located?

heating coil
Normally the freeze stat goes on the leaving face of the heating coil set at 38F. Sometimes with a hot water coil there will be a small freeze protection pump as part of the piping system to rat race water around at the coil to keep it from freezing in the event of a heating plant failure.

What causes evaporator freeze?

One of the most common causes of a frozen evaporator coil is lack of system airflow. If there isn’t enough air blowing over your evaporator coil, the coil won’t have enough heat to absorb. This will cause the condensation on the coil to freeze over. Dirty air filter.

How do you test a freeze sensor?

Locate your low temperature device and hold the ice pack on the front of the device for approximately 10 minutes or until the device activates an alarm. In most cases, the freeze sensor will cause beeping at the keypad so you will know something happened.

Why does my RV AC freeze up at night?

The majority of RV A/C freeze ups are caused by low airflow, usually due to dirty evaporator or condenser coils. The coils in your air conditioner unit—evaporator coils and condenser coils—need to be cleaned regularly. Ice will build up on the coils since the system has to work harder due to reduced airflow.

What is the sequence of operation for a freeze stat?

The sequence of operation for any freeze stat inside an air handler will include the following: When these valves open the appropriate pumps should energize. The pumps respond so that the water will flow through the coils. This prevents a freezing coil which will likely burst open if it freezes.

What is a freezestat and how does it work?

This is discussed below. A freezestat is a low-ambient-temperature-limit control device. It is the standard control used to achieve water-coil low-temperature protection. If air temperature at a coil drops to just above freezing, a freezestat changes over its contacts and initiates protective action.

How do I use the freeze stat?

You wire this freeze stat into your safety circuit to shut the system down should the air temperature drop below the setpoint in the freeze stat. One very important thing to remember about all freeze stats is that their sensors are averaging sensors, not remote bulb.

How do you use a freeze stat on an air handler?

The sequence of operation for any freeze stat inside an air handler will include the following: Stop the blower. Close all outside air dampers. Open the return air dampers. Open all valves serving chilled water or hot water coils inside the air handling unit.