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A backflow preventer on a heating system.

What is a Backflow Preventer?

The backflow preventer installed on your heating system is a device that allows water to flow in one direction but never back in the opposite direction of where it came from. In normal operation this device doesn’t do anything until your system calls for more water. The pressure on the supply side then moves the water toward your boiler. Should the supply pressure ever drop (fire dept opens a nearby hydrant, or a break in the main water line) the valve inside the preventer stops the water in the heating system from flowing back into and contaminating supply pipes.

Why is a Backflow Preventer Important?

In most places backflow preventers are legally required to be installed on a heating system. They are designed to ensure that contaminated water from your heating system does not flow back into the public water supply, which can pose a risk to public health and safety.

What Causes a Backflow Preventer to Malfunction?

Dirt or Debris: Dirt, debris, or other particles in the water supply can cause components of the backflow preventer to become stuck or clogged, preventing them from functioning properly.

Freezing: If a backflow preventer is exposed to freezing temperatures, the water inside can freeze and damage the internal components, preventing it from functioning properly.

Corrosion: Corrosion can occur within the backflow preventer, which can cause the valve or other components to become stuck or fail.

How Do I Know if my Backflow Preventer is Broken? How Will it Affect my System?

Reduced Water Pressure: If your backflow preventer is malfunctioning, it may restrict the flow of water through your HVAC system, resulting in reduced water pressure.

Water Leaks: A malfunctioning backflow preventer may cause a water leak. If you notice water pooling around your equipment or pipes, it could be a sign that there is a problem with the backflow preventer.

If left unaddressed, a malfunctioning backflow preventer can compromise the safety and quality of the water supply.

What to Do & What to Expect from a Levco Technician

The first step is to call Levco and explain the symptoms of your issue. If needed, a technician will be sent out to inspect the valve and determine the cause of the problem. Depending on the extent of the problem, the technician may recommend repairing or replacing the backflow preventer entirely. For example, if the device is corroded or worn out, it may need to be replaced. Cutting out the old valve and replacing it with a new one should only be performed by a qualified technician.