It is located next to your furnace or air handling unit inside your house, probably in the garage. There is a white plastic pipe that comes off of the unit to drain the condensate water from the evaporator coil. You need to twist and pull off the cap on the pipe and use a funnel to pour water into the drain pipe. The cap is located about a foot or so from the air handling unit.

Munn's for us also using a shop vac with water.
They said just use hot water once a month.

Now my neighbors use bleach in their water line.
The only thing people don't like with bleach is the smell in ventilation system.

Bleach can create fumes that can cause erosion of the metal parts in your air handing unit, especially the evaporator coil. I would not use bleach, unless you thoroughly flush it out with water after adding the bleach to the drain.

Where the does the water come out?

The water will come out of another plastic pipe outside of your house, most likely located behind the garage. There will be 2 pipes sticking up out of the ground, and you should see water dripping out of one of the pipes whenever your air conditioner is running. The other pipe is connected to the drain pan located under your water heater, if you have a tank type water heater. Water will only come out of that pipe if your water heater has a leak or the pressure relief valve trips. Note, that you may only have one outside pipe if you have a tankless water heater.

Ours comes out a pipe that is located right next to the ac unit behind the garage.

Thanks- very helpful

Vinegar is perfectly good can be used as mold remover and also as a fabric softerer.

Be careful with using vinegar if your exit drain is near grass or plants. Some are susceptible to damage.

Those do work, but you have to stop the backflow into the HVAC drain pan so that all the water's force goes out the drain line. To do that effectively you need a valve in the pipe between the hook up of the hose and the HVAC drainpan.

I have a contract with Sun Kool and they said the same thing. Just use hot water every few months. No Dawn or vinegar.

i vinegar for half hour, figure its done it's job, then flush with hot water monthly. Make sure hvac off at either switch or thermostat before starting this proceedure

Some years ago, I purchased a flexible hose at Lowes that fits nicely inside the inner diameter of the PVC drain line. I also installed a screen mesh over the outside end of the drain line to prevent insects and small critters from taking up residence inside the drain line.

I connected a female fitting on one end of the flexible hose. I then remove the PVC cap on the drain line and slide approximately 3 feet of hose inside the drain line. I then connect the other end of the flexible hose to the water hose. I remove the screening mesh and slowly crack open the bib valve to flush the line. I then reinstall the screening on the outside end of the drain line, remove the hose and reinstall the drain line cap. It takes about 10 minutes start to finish. Easy-peasy.

Hot water only no vinegar.

I was told to pour hot water mixed with some Dawn liquid every month or so.