Drainage Systems · Drain Traps
Trap Primer
A device that periodically injects a small amount of water into a floor drain or seldom-used trap, keeping the trap seal full so sewer gas cannot escape into the building.
Common uses
Maintaining trap seals on floor drains and infrequently used fixtures
Common symptoms
- Sewer gas odor near floor drains
- Dry trap
- Gurgling drains
Common repairs
- Primer valve replacement
- Supply line clearing
- Trap refilling
Related terms
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