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Backflow Enclosure - 400TDS-AL - 2 Doors - Safe-T-Cover



This American made backflow enclosure features a two door design. It is recommended to add the HCHS1000-120 Heater (1000 watt) to protect from freezing temperatures. This enclosure is made from marine grade aluminum, and polyisocyanurate insulation. The 400TDS-AL enclosure is easy to set up, lockable, and provides protection against vandalism to backflow preventers, meters, and other pumps and valves.

This enclosure meets ASSE Standard 1060 Class 1 for free protection when the recommended heater is added.


Model: 400TDS-AL

Weight: 546 lbs

Dimensions: 58" W x 106" L x 54" H

With or without HCHS1000-120 Heater

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  • Marine-grade aluminum construction material
  • All models are lockable for vandal protection
  • Easy access for testing and repairs
  • With heat, the enclosure meets the requirements of ASSE Standard 1060 Class 1 for freeze protection
  • Easy installation
  • Made in the USA

Other Backflow Enclosure Sizes and Models:

Aluminum Backflow Enclosures

Backflow Enclosures Protect RPZs from the Elements

Backflow Enclosures Are Superior In Extreme Cold Harsh Weather

Safe-T-Cover enclosures can handle the most severe, harsh weather and will perform perfectly. These enclosures meet the ASSE Standard 1060 Class I requirements.

Cold and blustering St. John’s Newfoundland in Canada has the harshest winter in North America. Its low temperatures average around -4°F and 14°F with a wind speed of 15 mph during the winter months. The area has approximately 167 days with the temperature below freezing each year. In comparison, Buffalo, NY has 124 freezing days each year, and Chicago, IL comes in at 122 freezing days each year with a wind speed of 7.4. In order to protect backflow preventers from these conditions, engineers in St. John’s turned to above-ground enclosures.

The Harsh Climate

The question arises, is St. John’s environment during the winter months suitable for above-ground enclosures? Yes! The cross-connection control engineers in St. John’s specified above-ground enclosures should meet the ASSE Standard 1060 as well as a number of requirements for ASSE 1060 enclosures that include strength, drainage, and security. The ASSE 1060 is extremely important for freeze protection and ASSE 1060 Class I requires the enclosure to maintain heat at 40°F inside when the outside temperature is as low as -30°F. How backflow enclosures achieve Class I is by the combination of insulation and a powerful heater.

All the panels in one of the enclosures are 1½” of polyisocyanurate insulation cut to the precise dimensions of the panel. The material is often used in the roofing industry and is considered superior to the sprayed-on insulation commonly used on a HotBox and other fiberglass enclosures. The R-value for polyisocyanurate is the highest for rigid-board insulation with an average of 6.5 per inch. Using this high-quality material allows for the enclosures to go well beyond ASSE-1060’s R-8 requirements for insulation. As hot air rises, most of the heat will escape through the roof. This is precisely why all panel-designed Safe-T-Cover enclosures have 3-inches of rigid-board insulation in the roof. That equals more than twice the insulation required for ASSE Standard 1060.

The majority of heaters in the industry are wall-mounted at a minimum of 12-inches off the slab. Keep in mind, as heated air rises, the most effective heating takes place when the heater is placed as low as possible. For maximum heat confinement, you need a heater that bolts directly to the concrete slab and produces both convective heat to the air and conductive heat to the slab. Heaters installed in his manner offer heat that penetrates as much as 16-inches down into the vertical riser pipes.

Large Backflow Enclosure

Aluminum Enclosures Should Be Lockable

RPZ Enclosure in Plants

Safe-T-Cover Enclosure Protects Year Round

For Extreme Freeze Protection

Safe-T-Cover has been selling standard enclosures and large custom enclosures in Newfoundland every year over the past 5 years. We know, firsthand, that backflow enclosures can withstand the extreme cold and high winds encountered on Newfoundland each year. They protect the equipment inside from freezing and provide testers and workers a safe place to perform their work. Because the winters are so severe, St.John’s Cross Connection Control engineers prefer those working on the equipment be housed inside the enclosures with enough room to work inside the enclosure for many situations.

The workers cannot be exposed to the harsh outside weather in the winter. Therefore, the manufacturer must design the enclosures much larger to make sure they have room to work. They must consider the size among a variety of design considerations when creating backflow enclosures suitable for this climate.Jim Sweetapple is head of J.D.S. Sales Ltd in St. John’s and he knows how important it is to provide a safe environment for workers. He understands the harsh climate conditions that require enclosures that offer the opportunity for service and maintenance of equipment while allowing workers a safe place from extreme wind and cold elements that are commonplace in St. John’s all year round.

Sturdy, long-lasting above-ground enclosures from Safe-T-Cover can handle the extreme weather in Newfoundland. The City of St. John’s cross-connection control office requires all backflow enclosures to carry ASSE 1060 certification. The availability of ASSE 1060 certified standard models and custom enclosures that are built to the ASSE 1060 standard have been an incredible success. You will discover that ASSE Standard 1060 Class I approved enclosures are a perfect fit for all your level of harsh winters.