Upflow vertical - drain exiting right side

What is going on

This is the hose and fitting job for sending the condensate drain out the right side of an upflow furnace. It looks fussy but it is just four connections. The things people miss are the hose cut line and the clamp sizes, and a loose clamp will drip. Take your time, check it fits, and then test with water before you close it up.

Likely causes

• Furnace installed with the drain on the right side
• Hose cut at the wrong line
• Clamps loose or the wrong size, causing drips
• Fitting installed with the barb end the wrong way

Check in this order

1. Install the 45 degree pipe/hose drain coupling from outside the cabinet through the right side hole, barb end inside. Secure with two #8 self-tapping screws.
2. Cut long drain hose #3 at line A.
3. Connect the large end of hose #3 to the trap outlet with a 1.25 in clamp.
4. Connect the small end of hose #3 to the 45 degree elbow with a 1 in clamp.
5. Connect the field drain to the furnace trap outlet per the field drain section.
6. Pour water through the trap and check for leaks at every clamp.
7. Make sure the hose has no kinks or low spots.

More furnace guides

• Airflow lower than demanded, furnace runs on low stage when high stage is expected
• Alternate combustion air opening (upflow or horizontal)
• Alternate vent/flue location (upflow or horizontal left)
• Annual inspection checklist
• Auxiliary limit control (location and purpose)
• Auxiliary limit switch open (blower compartment)