Loud drip noise in drain

[stardotstar]

Have had my downstairs unit off for about 2 weeks, since summer. Upstairs has run when necessary.

Tonight I turned on the down unit and I could hear a loud rapid drip noise in the sink in the bathroom where the drain line connects.

It only does this when the down unit comes on. Any thoughts? Both up and down drain via same sink.

[2hot2coolme]

Whatcha runnin the heat?

Maybe the humidifier drain is tied into that?

[trane]

Trap may be dry.

[coolcray3]

is it 90% furnace and does it have humidifier on it.

[stardotstar]

No humidifier.

Running AC

[tinknocker service tech]

did this just start this year or has it been on going
if there is no trap on the unit then you are hearing the condensate in the drain pan gurgling. if it just started it could be the filter is very dirty and causeing high static pressure in the return and pulling the air through the trap.

[stardotstar]

Ran fine all summer. Off for about 2 - 3 weeks. Turned ac back on tonight and hear the noise. Filters are clean.

There is a trap.

[coolcray3]

where is the furnace in location to the bathroom.

[stardotstar]

above and over 6 feet

[coolcray3]

is it possible that the sink trap dried up did you try running some water in the sink.

[trane]

It should stop after it cycles a time or two.

[coolcray3]

after the p trap fills. i thought the same thing but the sink trap should muffle the sound i would thnk.

[stardotstar]

Ran sink. will let it run overnight and report back, thanks!