Backflow Enclosure Freeze Protection

Safe-T-Cover offers heaters for aluminum enclosures to maintain freeze protection in even the harshest environments. To keep your device at a steady, warm temperature, you should consider a slab-mounted heater. Below are some of the most frequently asked questions we receive about heating aluminum enclosures.


Featured Video

Backflow Preventer Freeze Prevention

Learn more about the benefits of even heat distribution with a patented Safe-T-Cover slab-mounted heater, ASSE 1060-certification and how heated enclosures help prevent backflow preventers from freezing. 

Will I need heat for the enclosure?

In any area where temperatures can fall and stay below freezing for a day or two, our recommendation is to add heating to the enclosure. This seems to be one of those "pay me now or pay me later" type of decisions we all deal with. As a design engineer, specify an ASSE 1060 class 1 enclosure and you can rest easy knowing the owner will never call you and ask why the backflow device is frozen and who will be paying for an expensive backflow replacement bill. Not to mention the losses due to the building being without water until the repair is made. We routinely sell box heaters for projects in the traditionally warm southern states of Texas, Louisiana, Mississippi, Alabama, Georgia, and on occasion in Florida. Mother Nature can surprise us: even Florida and Nevada can freeze. This blog post about backflow cages goes into more detail.

What types of heaters are available and how do they work?

Wall Heaters

Most backflow cover heaters in the industry are wall mounted. This method is simply unable to deliver the same amount of freeze protection provided by a floor or slab-mounted heater. Because of the door configuration, wall heaters must be mounted to one side. And because they do not meet the wet/damp requirement, they must be mounted at a minimum of 12” off the slab. Remember that heated air always dissipates straight up, so these heaters’ warmth channels straight out of the top of the enclosure long before uniform warmth is achieved.


Slab Mounted Heaters

On the other hand, a slab mounted backflow cover heater provides heat to both the internal equipment as well as the up to 16 inches down into the riser pipes beneath the slab. These  heaters will maintain an interior temperature of 40° with an outside temperature of as low as  –30° as is needed to meet ASSE 1060 requirements. Safe-T-Cover’s patented slab mounted heaters are certified for wet/damp conditions. This is obviously necessary for waterworks equipment and really any enclosure that is not watertight. This unduplicated, rugged design has proven reliable for backflow preventer protection in severe environments for years. 


Heat Wrap Cable

We do offer a self-regulating heat cable. This heater type is wrapped around the backflow device. However, most enclosure manufacturers only provide the heat cable option for small diameter pipes only.

How much heat do I need and what voltages are available?

Safe-T-Cover offers the 1000 watt and 2000 watt slab mounted box heaters at 120V and 240V as well. You should set the thermostat for wall mounted and slab mounted heaters at 40 degrees and the heater will maintain this temperature all the way down to –30º degrees F. Safe-T-Cover has sold heated enclosures for many years in Canada and in upstate NY where winters can be long and the temperatures are well below freezing for many days at a time. For more information, you can read our case study from St. John's, Newfoundland about how well aluminum enclosures perform in harsh environments.

What happens if the power fails?

Be Prepared is the Boy Scout motto, and Safe-T-Cover also advocates being in a state of readiness. The first and foremost way to prepare against freezing pipes is to know the power has failed at the enclosure. We offer three different power and temperature failure alarms. There are simpler models with a light and alarm, and systems with remote monitoring and cell phone alerts. The second way you can be prepared is to have a plan in place to provide some type of box heating for the enclosure if it looks like the power might be out for an extended period of time and the temperatures will be below freezing while the power is out. A 9,000 BTU portable propane heater will more than replace the output of a 2,000 watt electric heater.

How is temperature controlled? Where is the thermostat installed?

For smaller diameter pipe sizes, most manufacturers provide a self-regulating heat cable. This video from Instrument Specialties Inc. gives an overview of how these heating cables work. For the other two heating options, the wall mounted and slab mounted enclosure heaters, a thermostat determines when the heater will be energized. Most wall mounted heater thermostats are built into the body of the heater and are located high enough on the wall for the heater to be safe from water damage. For slab mounted heaters, the thermostat is installed about 12” above the slab. The thermostat is set at 40 degrees and are designed to maintain this temperature inside the enclosure all the way down to – 30 degrees F. That is, if the box heater satisfies the ASSE 1060 class 1 requirements.


Model Number







Length (in.)



Assembly Instructions

List Price Sheet

Chromalox-30 Cable 120 90 0 Single 0.75 216.00 specification submittal instructions $132.00
HCH2000-120 Slab 120 2000 6824 Single 16.66 37.00 specification submittal instructions Not Sold Separately
HCH2000-240 Slab 240 2000 6824 Single 8.33 37.00 specification submittal instructions Not Sold Separately
HCHS1000-120 Slab 120 1000 3413 Single 8.33 23.00 specification submittal instructions Not Sold Separately
HCHS1000-240 Slab 240 1000 3413 Single 4.16 23.00 specification submittal instructions Not Sold Separately
HCHS500-120 Slab 120 500 1707 Single 4.16 23.00 specification submittal instructions Not Sold Separately
Chromalox-HVT-2411W Wall 120 2000 6824 Single 16.66 28.00 specification submittal instructions $918.00
King-U12100-SS Wall 120 1000 3412 Single 8.33 17.00 specification submittal instructions $669.00


Please contact us by filling out the form via the button below.
We're in the office 8am-4pm Central Time, Monday through Friday.