Where backflow devices are found
- Restaurant kitchens and coffee shops with carbonators
- Dental and medical offices
- Sprinkler feeds in plazas and towers
- Lawn sprinkler zones around condo grounds
- Boilers and chemical feed lines in mechanical rooms
How a test is done
- Confirm the device type: double check valve or reduced pressure zone
- Shut the downstream valve briefly and connect the test gauge
- Check each valve holds and the relief opens at the right point
- Record readings, open the valves and restore service
- Prepare the test report for submission
Margin note: Toronto Water has a backflow prevention program with its own deadlines and forms. Check the current requirements with the city before your test is due; we can file the paperwork with you.
When a device fails
- Fouled or worn check valve rubbers are replaced with a rebuild kit
- Relief valves that dump water constantly are cleaned or rebuilt
- Devices that cannot be rebuilt are replaced with a matching unit
- The device is retested after repair so the report shows a pass
Planning the shut-off
A test takes the water off briefly downstream of the device. In a restaurant that means planning around prep; in a building it may affect the sprinkler line, which can need the fire alarm company notified. We sort this out on the booking call so nothing comes as a surprise.