Central air conditioner issues on a rental house in Texas.

June 29, 2008 3:45 PM

Air conditioner puts out more water than cool air. Ideas on what two renters can do?

The Texas summer is obviously too much for our new rent house to handle. With the thermostat at 78 degrees, it puts out at least 28 quarts of water per day (14 gallon bucket emptied twice, sometimes three times each day). While that's good for the herbs in the front, it's not so good for the internal temp of the house - the cooling cycles are long and do little to bring down our 80+ degree house to the thermostat setting. It also makes a loud noise when starting, almost like someone is kicking the housing unit. This is a central air-unit, not a window-based.

Being renters, there's not much else for us to do other than replace the filter (done when we moved in) and call the landlord to send someone out to inspect it, which we have already. The technicians said the Freon level was fine and cleaned debris out of the unit and while that helped somewhat, it obviously wasn't sufficient, as our most recent electricity bill was $lots.

To hone it down to something specific, we'd like to look for terms/questions to pinpoint to our (granted, a bit batty) landlord. The leakage is a major concern, as is the cost of the electric bill.

Getting the fuck out of Dallas isn't an immediate solution.

posted by Ufez Jones to home & garden (9 comments total)

Every house that I've lived in that's had central A/C had some way of automatically draining the condensate water that naturally accumulates on the coils to the outdoors.

Where the evaporator (cold coils) has been in the basement, the typical arrangement is a pump on the side of the furnace housing. It has a motor triggered by a float switch, with a reservoir of perhaps a quart or two. When the reservoir fills up, the pump kicks on and forces it outside. (In most arrangements I've seen, the waste line is a flexible 1/2" hose running next to the coolant line out of the house, sometimes with a U-bend in it somewhere.)

In houses I've been in where there wasn't a basement and the evaporator was on the main floor, there was always a waste line that ran either out of the house completely (again, typically paralleling the coolant line outside to the compressor) or to a floor drain.

I've *never* seen a central-air system that required you to manually empty buckets of condensate water. That doesn't just seem like a bad design, it seems broken. Some portable A/C units work like that, but that's one of their major drawbacks.

I can tell you that when I was in a house where the condensate pump broke, a central A/C unit can produce a lot of water (gallons and gallons of it) in a surprisingly short amount of time. So the volume of water you're talking about doesn't seem at all out of line, if the humidity in your area is high. If you've ever used a dehumidifier, they can produce 15 qts/day easily, and they're a lot smaller and move a lot less air through them than a typical 1T central A/C unit.)

Better insulation and air-tightness will help cut down both on cooling costs and the amount of condensate produced in the evaporator, but that's probably not really an option in a rental house.

I guess if I was in your shoes, and I really couldn't convince the landlord that a central A/C shouldn't have a manually-emptied water bucket involved in its operation, I'd probably buy a little float-switch operated utility or sump pump (Home Depot in my area has several), and put it down in the catch bucket. That way, when the bucket gets a few inches of water in it, the pump will kick on and pump the water outside. I'd run the waste line to a drain (if you have one handy) or outside if you can find a way to get it there.

I've used a setup like that with a dehumidifier in order to keep basements dry without having to constantly empty dehumidifier catch-buckets, and it worked fairly well. I ran the line from the pump (which I placed in the dehumidifier bucket) to a laundry sink. It's not the sort of thing I'd trust to run if you're leaving the house for a week, but it's a nice labor-saver.
posted by Kadin2048 at 4:19 PM on June 29 [1 favorite]

Unfortunately, the water coming out of the air conditioner is a normal by-product of its operation. Air conditioners will cool air to the point where water starts condensing out of the air (think of water drops on the side of a glass of ice water). The problem is that it takes a lot more energy to condense water out of air than it does to cool air without condensation, so when the air coming out of the air conditioner is at the air's dew point, you probably won't get the air any colder.

I see that in the past week the dew point in Dallas, Texas has hovered between 60 and 70 deg F; that means your conditioned air won't get much colder than that. Usually air conditioners put out air at about 55 deg F.

One solution might be to invest in a dehumidifier. Seal up the house, flip on the dehumidifier and AC, and empty out the rapidly filling water tank periodically. This, unfortunately, won't do any favors for your electric bill, but it will help cool the place down. Other things you can do involve reducing the amount of heat entering the house, but they are more permanent landlord-type solutions; things like painting the house a light color, installing an attic fan, installing extra insulation; etc.

I would imagine a central air conditioner installed in an environment like that would have some sort of permanent method of draining away the condensate, so the condensate doesn't spill everywhere. Is there such a drainage system, and is it in good working order? That is something you could get the landlord to address.
posted by zompus at 4:31 PM on June 29

When I moved into my rented house, the air conditioner (central) wouldn't cool the house down below 80ºF. I called the property management company and explained that it didn't work. Someone came out and fixed it. Therefore the house was cool when I wanted it to be. I live in the SE USA, and while it's not quite Dallas, it's certainly hot. This weekend we hovered around 100ºF.

Your air conditioning doesn't work. You're paying a lot of money because of that (or despite that, however you'd like to look at it). Hound the landlord. Explain that the company that came out to inspect didn't fix the air conditioning. Clearly it wasn't (just) a freon issue. The water may be a red herring (or maybe not...it's certainly a bizarre thing, as I'm not experienced with indoor condensation).

Be tenacious.
posted by Stewriffic at 4:54 PM on June 29

The amount of water the thing is producing does seem excessive, but then again every central air system I've ever encountered has the condensation piped directly into the sewage line so I really have no metric.

Have you tried measuring the temperature of the air coming out of the vents? It should be about 55 deg F (~13 deg C). If it falls reasonably close to this, your problem is a poorly insulated house and not the A/C.
posted by wsp at 5:10 PM on June 29

One more thing: have you checked nearby water lines for leaks? I'm assuming the indoor portion of the A/C is mounted inside a furnace. Maybe the lines leading to, say, a humidifier have sprung a leak? Because there would really be nowhere else for the water to be coming from besides condensation.
posted by wsp at 5:19 PM on June 29

No reasonably sized air conditioner will be able to cool an indoor space that has a significant amount of air exchange with outdoors. The fact that your unit is making vast amount of condensate says to me that this is what's happening. Water doesn't appear by magic - it condenses out of the air being fed into the A-C's air intake, and if the A-C just keeps on producing loads of it all day, that means that (a) it is cooling the air, so it's working and (b) there's a continuous supply of humid air arriving at the intake. There shouldn't be.

Before you conclude that the A-C is broken, do make sure your living space is properly closed down. If you've got exhaust fans running, turn them off. If you've got windows and/or doors open, close them. If your house is properly sealed up, the A-C should wring lots of condensate out of the air for a couple hours after you turn it on, then settle into the job of cooling down the now-dry inside air.

Zompus has it exactly right, except for the advice about wanting a dehumidifier. A dehumidifier is just an A-C that doesn't separate its cold air and hot air output streams. You don't want any more heat being released into your space than you can help, and a dehumidifier will have a net heating effect. You already know your A-C is operating as a dehumidifier - you can see the buckets of water it's sucking out of the air.

Also, be aware that a square metre of glazing in full sunsihine will let about a kilowatt of heat into your living space. If you've not already fitted blockout blinds or curtains with a white reflective side toward the window, or exterior blinds or shutters or awnings, look into those.
posted by flabdablet at 7:12 PM on June 29 [2 favorites]

I know this doesn't directly answer your question, but have you considered blackout curtains? The one's I have are a thin layer of what appears to be very dense foam. They hang behind the normal curtains, so you can't see them in the room, and they're pale cream in colour, so they don't look odd from outside. I mention them because I have 2 rooms on a SW facing exposure, and only one room has the curtains installed. There is a real and quite appreciable difference between the temperature in the two rooms on a hot summer's day.

It might be obvious, too, but are you keeping the windows closed? I never used to, until I realised that I was just letting more energy into the mix.

I figure that the less work you make the AC do, the cheaper your electricity bill and the more effective it's going to be.
posted by Solomon at 3:09 AM on June 30

Dude, I had a leak from my A/C last year that was really, really bad. As in, water was leaking through my roof, through the GARAGE DOOR OPENER, and into a LIGHT SOCKET.

After some probing, a nice guy named Travis Huxley figured out that the unit was hung crookedly, and the pan under the unit that was there to catch water was actually just pouring the water onto the floor and everywhere else. Because the unit was hung crooked, it had worked about 4 years just fine, then started to break down, because they have to be level.

It sounds like the same problem you have... your unit may be set in a way so it's not level. I thought it couldn't possibly be a big deal, but this caused us to leak Freon, the coils to get banged by the fan, which damaged them, and basically I had to replace the entire thing four years into a brand-new house. Can you get near it and check it with a level? Mine kept freezing up and would never cool below 80 degrees, so I'm worried this could be the same problem you had.

Unfortunately I just called Travis and his number doesn't work any more... bugger. I mean, we live just around the corner from you guys and ours is working at least enough to cool it to 75...

I would imagine the landlord will choose the person to work on the unit regardless, but maybe you guys could find out the average bill for your zip code from your energy provider, show your landlord the difference, and explain to him that it's only fair to deduct that amount from your rent until he gets someone to genuinely fix it?
posted by Unicorn on the cob at 3:39 PM on June 30

Thanks all. From what I gleaned here and a conversation I had with my father tonight, I think we at least have somewhat of a grasp as to how to handle the issue.

As far as the leakage goes, I'm sorry if I (or frankly, the SO, who typed up the majority of the initial question) didn't clarify, but the condensation line actually runs out of the front of the house from a PVC pipe that hangs off of the front awning. The Central Unit itself is in the backyard. They're obviously directly connected - as in, it doesn't drip when the A/C isn't on, but when the A/C is on, it leaks badly.

I've come to a few certain conclusions, though:

This house, which we've (thought) we'd gotten a great deal on, is a first time renter for the landlords. Our previous place, which was older, but somewhat better maintained, had been rented out for at least 10 years. I suspect this has something to do with it.

That said, I pored over the shocking(!) electric bill that we received and figured out that at least half, if not 3/4s of it dates involved were based on the time between when we moved in and the A/C technicians came. That probably had a lot to do with it. Also, I don't know if this is a new thing or not, but apparently TXU is charging premium prices as well during the months of May-Oct.

I've got two plans of action for tomorrow: The first is calling the electric company to find out if there were significant rate changes between OMGTX Heat 2k7 and OMGTX Heat this year. #2 is meeting up with a good friend that happens to have one of those laser/infrared thermometers so we can re-check the air coming out of the vents and ensure that the seals around the doors/windows aren't leaking anything.

Any additional advice would be well received. Thanks and thanks.
posted by Ufez Jones at 10:00 PM on June 30