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Condensate Recovery System

Primary condensate line before installing the valve assembly.

Primary condensate line before installing the valve assembly.

Valve Assembly

Valve Assembly

The Condensate Recovery System Theory

A Do it Yourself residential gravity -assisted air conditioning (AC) condensate reclamation device which will reclaim up to 5-9 gallons of water or more per day.

There is over 3 quadrillion gallons of water in the earth's atmosphere at any given time. Water is partly responsible for that "feels like" temperature the weatherman is always referring to. The moisture in the air makes the heat more uncomfortable. Air conditioners cool off the room by removing heat and by removing moisture from the air. AC ‘s evaporate and condense the water in the air, then dump it on your yard, or into the sewer system!

The typical AC unit is designed to leave the room at 55% relative humidity (so everything doesn't dry up and crack). In other words, your AC removes 45% of the relative humidity in the air. This water is typically diverted to a pipe which runs into the bathroom sink drain, and is carried away by the sewer system. Other units simply dump the water, perhaps, on the ground near the fan unit, causing a muddy spot in the yard.

A 12,000 BTU/hr AC unit typically produces about 880 gr per hour or .8 liters. About 5-9 gallons per day, on the average. Of course there really isn't an average. It is all dependent on variables, such as, AC unit size (1 ton, 2 ton, etc.), thermostat setting and how many widows facing the sun.

My AC unit, in Cedar Park, Texas, produces about 9 gallons per day currently (about 3 oz every 7.5 minutes). Which translates to potentially a couple of thousand gallons collected per year. That is water I have paid the electrical utility company to produce and (in the past) paid the waste water management company to recycle. In addition, the water collected this way I will not have to purchase from the water company. Our temperatures have been in the 90-103 degree range. Humidity has been 20-35%. Of course, one needs to check their own for exact quantities of condensate produced, but definitely you will have more than enough to water your indoor house plants, or a small garden. You may also begin filling up your rain barrel in times of drought.




Attic Parts (apx. $20)

One ¾” x 10’ Schedule 40 PVC pipe

One PVC Handy Pack (Primer & cement)

Pipe insulation tube

Three 45’s and one elbow

Two ball valves

One T

Reclaimer Parts (apx. $45)

One ¾” reducing flush valve

One 4” x 2” reducer

One 10” x 4” PVC pipe

One 4” coupling

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One o-ring and washer kit

One 4” female adapter and threaded plug

Two ¾” plastic hose bibs

Two 2/4” threaded bushings

One tube of caulk

One or 2 concrete stepping stones for slab

Optional Parts

Electronic Water Timer (Vigoro)

Water Hand Pump (Pump Away)

Water Tank (plastic barrel/drum, etc.)

Drip Line

Hardware (apx. $15)

Metal strapping

Lead shield masonry anchors with screws

2 1” wood screws


Screwdriver or screw gun


1 inch Forstner or paddle bit.

Measuring tape

Magic marker

Masonry bit

Paint brush

Caulk gun

Saw to cut ¾” pvc


Top Section with Trap

Top Section with Trap


These are the instruction for the 4” x 8’ PVC condensate Reclaimer. Watch the movie several times until you understand it. You may want to scale your Reclaimer up or down, add a pump, larger storage unit, or automatic water hose bib timer. Adjust the parts list accordingly. Go to a Home Depot or other home center and purchase the items in the parts list. Have someone there cut the 10 foot 4” pipe into 2 pieces (one 6’ and one 2’. There will be a third 2’ piece left over which you may need if you screw up the other 2’ piece).

Tie into your AC units primary condensate line. It runs down into a bathroom sink drain. The valves can be open or closed. One should always be open so that the water either drains into the primary original pipe or into the condensate Reclaimer line. It is preferable to do it this way, instead of just tying into the existing secondary drain pipe. This is set to drip over a window or door so that it does not go unnoticed. Water coming from this line lets you know that your ac seal is faulty and is leaking. Unit needs major repair or replacing at this point!

Measure twice, cut once. Lay everything out to check it before cementing joints.

The attic work is the most difficult because of enclosed and hot space. Be careful of nails and hitting your head. DO NOT stay in the attic longer than a few minutes at a time. Do a step and then rest from the heat and drink water.

Drill a hole from the outside under the soffit board for the exiting pipe. In the garage, or under a shady carport, glue all the pieces that you can before taking them into the attic. Check for leaks in everything before taking it up into the attic. You have only to glue three joints on the valve assembly and exit pipe. Some fumes involved with primer and cement, so be careful when gluing pipe in the enclosed space. Be sure to have enough of an incline in the exit pipe in order to facilitate movement of the condensate by way of gravity assist.

Test it by shutting the primary valve (original line) off, and the new Reclaimer line on. Put insulation on the pipes to keep condensate from forming and dripping inside the roof. That’s all there is to the attic.

The rest of the Reclaimer is made up of two segments. The eight foot piece of 4” pipe forms the top part of the Reclaimer and the 2 foot piece. Cement the 4” to 2” reducer (cap) onto one end of the 8 foot pipe. Drill a ½” hole just below the cap.

Take one of the 2 foot segments of 4” pipe (put the other away for a spare) . Glue the 4” female adapter onto end. Hand tighten the threaded end cap. Glue the 4” coupling onto the other end. Drill a one inch hole apx.5 inches from the end cap, and another one above that. These are for the plastic hose bibs. Make room for a bucket to fit under the top hose bib. Use the rubber o-rings on the inside and on the outside of the pipe. Use silicon on both sides with the o-rings. Tighten the threaded couplings, but don’t over tighten. Test this unit segment for leaks.

Glue the reducing flush valve onto the ¾” pipe on the outside where it exit’s the roof. Make sure that you use a small strap and the 2 wood screws to attach the pipe inside the attic before exiting.

Put enough play sand or aquarium gravel into the bottom of the small segment to fill up to the bottom hose bib. Make sure the valves are turned off. Use silicon to glue the two segments together. Don’t use too much, we may need to remove just this one segment for maintenance, or to replace with the optional water drinking filter segment.

Put a cement pad down and place the unpainted Reclaimer onto the pad while sliding the reducing bushing into the reducer cap, you can use a twisting action, or pre-grease the joint with petroleum jelly. Measure the needed height for the pad and for the placing of the masonry anchors.

Take the unit back down and paint it and the straps. Once the paint has dried, mount the Reclaimer as before and attach the clamps securely in place. Use auto timer on the hose bid to dump into a bucket or hose. Or collect water manually. WATER YOUR PLANTS.

Find the video here:

Condensate Recovery System

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