How can a trap seal be maintained?

How can a trap seal be maintained?

• A. periodically filled or topped off
• B. Ventilated with air
• C. Replaced with new seal
• D. Pumped out completely

Answer: (A)

Trap seals rely on a water barrier to block sewer gases and pests. Over time, the water can evaporate or be siphoned away, so the protective seal can be lost. Regular maintenance means replenishing the water to restore the correct depth of the seal, which is why topping off the trap periodically keeps it functioning. Ventilating with air would break the water barrier and let gases escape, so that action doesn’t maintain the seal. Replacing the seal isn’t how a trap works—the barrier is the water layer, not a discrete material that needs swapping. Pumping out completely would remove the water barrier entirely, defeating the purpose of the trap. So, periodic topping up of the trap with water is the proper way to maintain the seal.

Trap seals rely on a water barrier to block sewer gases and pests. Over time, the water can evaporate or be siphoned away, so the protective seal can be lost. Regular maintenance means replenishing the water to restore the correct depth of the seal, which is why topping off the trap periodically keeps it functioning.

Ventilating with air would break the water barrier and let gases escape, so that action doesn’t maintain the seal. Replacing the seal isn’t how a trap works—the barrier is the water layer, not a discrete material that needs swapping. Pumping out completely would remove the water barrier entirely, defeating the purpose of the trap.

So, periodic topping up of the trap with water is the proper way to maintain the seal.