Trap primers are used in plumbing systems to prevent floor drain traps from losing their water seal by evaporation. Maintaining the water seal will prevent the backflow of sewer gas into the buildings or rooms where the traps are installed.

What is trap seal?

Definition of trap seal

: the sealing value of a trap as measured vertically from the mean liquid surface level down to the dip of the trap.

How do you attach trap seal primer?

If using trap seal primer, insert connection tube into primer adapter. Otherwise, remove adapter. Apply thread seal tape to threads of primer plug and screw in plug to seal the outlet.

Is a trap primer necessary?

A trap primer is a fitting that drips water into a copper or plastic pipe that is connected to a floor drain P-Trap. It does that so the floor drain does not dry out. They are required so sewer gas does not come out, but they are not always required.

Where do you put trap primer?

The trap primer valve should be installed vertically at least twelve (12) inches [305mm] above the grid of a floor drain, or the flood rim of the equipment which the trap is to serve.

What is a trap seal primer outlet?

A trap primer (or trap seal primer) is a plumbing device or valve that adds water to traps. The trap primer mitigates this problem by injecting water, either directly or indirectly, into the trap to maintain the water seal indefinitely.

How does trap primer valve work?

A trap primer is a device that causes a small amount of water to drain to the trap via piping from the trap primer. It is an elastomeric type check valve/flapper that opens to allow water to flow and closes in a no-flow condition to prevent trap seal evaporation.

How does a pressure drop trap primer work?

Trap-Defender™ is a pressure drop trap primer designed to be connected to any potable cold water line. It is automatically activated when a valve or faucet is opened and the system experiences a drop in pressure. Water is released into the floor drain’s P-trap to maintain a seal.

How does a waterless trap seal work?

Often employing a type of flexible self-sealing membrane, waterless traps open during use and allow waste water to flow through the fitting, but close once the waste water drains through the fitting. This self-sealing action allows water to flow, whilst preventing foul sewer gases from entering the building.

How do you maintain a water seal in a trap?

Traps should be designed so that deposits such as hair, soap and food waste for example do not accumulate in the trap after a discharge through the trap. The internal surface of the trap should be smooth throughout. All traps should be accessible and should be self-cleaning.

How far can you run a trap primer?

Trap Primer valve makeup line to floor drain is recommended to be a minimum of 12” off the finished floor before a 90° elbow can be installed. The furthest recommended distance of makeup line is 20′ to the floor drain.

How much water does a trap primer use?

A water-supplied trap primer typically uses 4-8 ounces of water at a time. Some models are adjustable. After adding evaporation and multiplying the number of drains in a commercial building, the water use can quickly turn from ounces to many gallons per hour.

Does a floor drain need a trap primer?

Floor drain or similar traps directly connected to the drainage system and subject to infrequent use shall be protected with a trap seal primer, except where not deemed necessary for safety or sanitation by the Authority Having Jurisdiction. Trap seal primers shall be accessible for maintenance.

What is electronic trap primer?

Electronic Trap Primers deliver a timed discharge of water to the floor drain P-trap to ensure the traps maintain a water seal. A factory pre-set timer is programmed to discharge water to the trap every 24 hours.

How do I keep my P-trap from drying out?

P-traps can dry out as quickly as a month, sometimes even less than that. This happens most often in winter. To prevent your P-trap from drying out, run the sink or shower for a minute or two once a week to keep water flowing and your P-traps from drying out.