HVACopediaTrane · Furnace troubleshooting
Horizontal venting through a wall
What is going on
Wall-vent terminations must sit clear of expected snow and must not sit where condensate or staining can cause trouble. Vent pipe must slope upward so condensate drains back to the furnace.
Check in this order
- Keep the vent and inlet terminals at least 12 in above the highest expected snow level or grade, whichever is higher.
- Keep the terminal away from public walkways, soffit vents, crawl space vents, and any spot where condensate or vapor can cause a nuisance or damage.
- Slope the vent upward at 1/4 in per foot so condensate runs back to the furnace.
- Support horizontal pipe at no more than 3 ft intervals, with the first support as close to the furnace as possible.
- Do not let the furnace, blower housing or inducer carry the weight of the flue pipe.
- Keep the elbow and tee as close together as possible.
- Do not route return air through the side of the cabinet on horizontal applications.
Applies to: Upflow and downflow furnaces in horizontal venting
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Source: Trane installer's guide, p. 24-26. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.