Direct vent: alternate horizontal termination (Options 4 and 5)

What is going on

Alternate horizontal termination with the intake and exhaust spaced as shown. Option A requires a trap in the combustion air pipe. Option B does not. Wall penetrations and terminations must use 2 in pipe, and a 3 in vent may be necessary to step down to 2 in.

Check in this order

1. Keep the termination at 12 in above grade or expected snow level (U.S.).
2. Keep intake and exhaust spacing as shown 3 in minimum and 5 in maximum at the termination.
3. Keep the intake about 12 in from the wall and the exhaust about 6 in minimum from the wall, per the figure.
4. For Option A, install a trap in the combustion air pipe (RXGY-D05 for 2 in or RXGY-D06 for 3 in).
5. For Option B, no trap is required.
6. Limit 2 in pipe inside the wall to 18 in maximum when using 3 in vent.
7. Install the wind deflector vane in a 2 in PVC coupling in the vertical position using PVC solvent.
8. Make the intake and exhaust terminations in the same pressure zone.
9. Do not use screens or tees at the termination.
10. Insulate external piping as required for local climate.

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