Flomatic PVB 1 Installation Manual

Pressure Vacuum Breaker

Models PVB ¾“ &1”

Max Pressure – 175 PSI (12 BAR)
Max Temperature - 140ºF (60ºC)

Basic Installation Instructions

CAUTION: Installation of Backflow Preventers must be performed by qualified, licensed personnel.
Faulty installation could result in an improperly functioning device.

NOTE: CHECK WITH GOVERNING AUTHORITIES FOR LOCAL INSTALLATION REQUIREMENTS.

The installer should be sure the proper device has been selected for the particular installation.
The Danfoss Flomatic PVB contains an independently operating internally loaded check valve and an

independently operating loaded air inlet valve located on the discharge side of the check valve. When the
discharge pressure drops to 1 psi or below, the air vent opens and the spring loaded check valve closes the
valve inlet, preventing back-siphonage. During normal flow, the water opens the check valve assembly and
seat the vent disc holder against the bonnet as the body fills with water. The assembly is equipped with two
resilient-seat quarter turn shut-off valves and two test-cocks

The Danfoss Flomatic PVB is designer to prevent back-siphonage of contaminated water into the potable
water supply.
NOTE: Installations must have continuous pressure with no back pressure. For installations requiring
protection against backpressure install a Danfoss Flomatic RPZE or RPZE II.

Installation

The Danfoss Flomatic Model PVB must be installed in a vertical position with the supply connected to the
bottom of the assembly, as shown above. The valve should be installed with adequate clearance on all sides
to allow for periodic inspection, testing, and maintenance. The Assembly must be installed at least 12" above
the highest downstream outlet. Do not install in a pit or vault. Protect the device from freezing. The
Assembly must not be installed where back pressure is present.

In case of possible warranty claim, contact your local supplier or Danfoss Flomatic representative. DO NOT

REMOVE ASSEMBLY FROM THE PIPELINE.

The assembly must be protected from freezing and excessive pressure increases. Pressure increases can
be caused by thermal expansion or water hammer. These excessive pressure situations must be eliminated
to protect the valve and the system from possible damage. For protection against water hammer shocks,
install a water hammer arrestor utilizing good plumbing practice.

Placing the Device in Service
After proper installation of a Danfoss Flomatic Model PVB, place the unit in service as follows:

1. Begin with both Shut Off Valves closed. Pressurize the system up to the Model PVB.

2. Open Shut Off Valve #1 completely. Some spillage may occur from the Canopy until the unit is

pressurized.

Note:

Do not install in an area where the spillage of water may cause damage or be objectionable.

Installation Instructions

Danfoss Flomatic

Danfoss Flomatic Corp, 15 Pruyn’s Island, Glens Falls, New York 12801

Phone: [phone] Fax: [phone] www.flomatic.com

Rev. 4 (7/09)

PVB

Pressure Vacuum Breaker

Models PVB ¾“ &1”

3. Slowly open Shut Off Valve #2 to pressurize the downstream system. The Model PVB is now in service.

4. After the Model PVB has been properly installed and placed in service, the unit should be tested (See

Testing Procedures).

NOTE: Annual inspection, testing & cleaning of valves / system is required. This will help to insure
maximum life and proper function.

MAINTENANCE INSTRUCTIONS

1. Turn off the water supply to the Model PVB.

2. Release the pressure from the device.

3. Remove the Canopy Screws and Canopy.

4. Unscrew the bonnet from the body.

5. Remove spring clip (item 18) using needle nose pliers. Squeeze clip and disengage from side wall, then

remove. Note:

6. Unscrew the Check Valve Assembly from the body. Note:
hot water heater element wrench with the sides ground down will also work, consult factory for other tools.
A hot water heater element wrench with the sides ground down will also work. Consult factory for other
tools.

7. Clean and inspect all components thoroughly prior to reassembly.

8. Vent and Check Valve Silicone Disc are reversible.

9. Replace parts as needed and reassemble in reverse order.

Testing Procedures
Test No. 1 Air Inlet Opening Point
Purpose: To determine the pressure in the body when the air inlet valve opens.
Requirement: The air inlet valve shall open when the pressure in the body is no less than 1.0 psi above

atmospheric pressure, and the air inlet valve shall be fully open when the water drains from the body.

Steps:

a. Remove the Canopy.
b. Bleed water through both testcocks to eliminate foreign material.
c. Install appropriate fittings to testcocks.
d. Attach the high side hose of the differential pressure gage to

Testcock #2, slowly open Testcock #2, make sure the end of low hose
is level with Testcock #2.

e. Bleed air from the hose and gage by opening the high side bleed

needle valve. Close the high side bleed needle valve.

f. Close (outlet) Shut Off Valve #2, then close (inlet) Shut Off Valve #1.
g. Slowly open the high side bleed needle valve no more than one-

quarter (1/4) turn, being careful not to drop the differential pressure
reading of the gage too quickly. Record the differential pressure
reading of the gage when the air inlet valve opens, must be greater
then or equal to 1.0 psi.

h. Close Testcock #2.
i. Remove equipment.

j. Open Shut Off Valve #1.

Test No. 2 Check Valve Closing Point
Purpose: To determine the static pressure drop across the check valve.
Requirement: The static pressure drop across the check valve shall be at least 1.0 psi.

Starting July 1st 2005 on serial numbers P0001 and larger.

Installation Instructions

A 12 point 1-3/8" socket is recommended, a

Shut Off Valve #2

Testcock #2

Danfoss Flomatic

Testcock #1

Shut Off Valve #1

Danfoss Flomatic Corp, 15 Pruyn’s Island, Glens Falls, New York 12801

Phone: [phone] Fax: [phone] www.flomatic.com

Rev. 4 (7/09)

PVB