My AC says it isn't working.

Mundane Pointless Stuff I Must Share (MPSIMS)
#1

It was > 110 degrees (~44 Celsius) here today, and I got home from work (AC off all day) to a thermostat that read 95 F (35 C). Immediately I flipped on the cool and sat down to read a bit of the old Dope. After an hour or so I went out again to have dinner (leaving the AC on), and I ended up staying out until after midnight.

I came home to a thermostat that read 95 F (35 C). The fan is blowing cool (not frigid, but cool) air, and periodically hissing (not a comforting sound at all). I have no idea what might be wrong, but I have a ceiling fan that’s helping a bit. The number on the (electronic) thermostat hasn’t changed at all.

I’ll call the landlord tomorrow, but for now the heat is keeping me awake. Doesn’t help that my glorious memory foam bed absorbs heat like none other. Any suggestions for the mean time? I’m tempted to pit this heat wave.

#2

Cool air, like it’s cool because it’s just blowing or cool air like it’s just not cold enough? Since it ran for a few hours and it’s still 95, I’m guessing it’s not blowing any conditioned air, it just feels cool because it’s moving.

Is the compressor (the outdoor part) running?
Also, since it’s been hours since you turned it on, even it it’s not running now, put your hand on top of the unit and see if there’s heat pouring off of it like it possibly was running and it just isn’t right now.

Since I likely won’t be awake/around to get the answer to this question…
Go down to the basement (or wherever the air handler /furnace is) and see if there’s water coming out of the drain. If there is, hell, even if there’s not (since you have someone coming to look at it*), turn to T-stat to Fan switch to ON and let the furnace fan run for an hour or two and see if that makes a difference. Keep an eye on the drain and see if water starts pouring our after a while. If you can, live the AC off while you’re doing this. If it’s really humid out, the coils may have frozen up as soon as you kicked the AC on.

There’s several other possibilities, here, but this is the easiest thing for you to fix yourself.
Also, while I’m a believer in turning your AC off (or UP anyways) while you’re at work, when it’s THAT hot out, you really can’t do it. You’re AC is really going to struggle to bring the house down from 95 degrees, and if it’s humid out (and in the house for that matter), that may be the problem. Hopefully that’s all it is and running the fan for a bit will thaw out the coils.
If that’s the case, maybe when it’s that hot out, instead of turning your AC off when it’s going to be 100+ out, just set it to, say, 85 or so. That way it runs a little bit during the day and doesn’t have to work so hard when you get home and (more importantly) keeps the humidity in check.

*If someone gets there before while you still have the furnace fan running, say “I was thinking maybe the evaporator might have been iced up so I turned the compressor off and turned the fan on to see if it would defrost, I was just about to see if the compressor will kick back on” and then turn the fan switch to OFF and turn the AC back on. He’ll be impressed with your mad HVAC skilzz.

#3

This sounds like very good advice, but I’m not sure I can apply it. I live in a multi-unit apartment building, and don’t have access (as far as I’m aware) to the furnace fan. And yes, the air probably only feels cool because it’s moving, but I was hesitant to say it wasn’t cooled at all by the AC, since the air circulation + ceiling fan did make my bedroom slightly cooler – the thermostat only said 93 degrees this morning.

I will check to see if the outside unit has frozen up, though. Can’t believe I didn’t think of that last night. :smack:

HVAC man should be coming to check on it while I’m at work, so hopefully I’ll know soon what the problem is/whether I need to camp on a friend’s couch for the weekend. Thank all the gods for prompt service even on Fridays and (hopefully) easy fixes.

#4

That sounds like it’s just a matter of stirring the cool air up off the ground or out from cooler areas of the unit. A drop of 2 degrees (to me) says the AC isn’t running at all.

It would be the inside unit that’s iced up. But I’ve lived in some apartments where the “inside unit” is located physically outside. It’s that part that’s inside the furnace that gets full of ice. Yes, most people (even home owners) don’t really have access to that, but just turning your AC off and setting the fan switch to ON, will melt any ice if it’s on there.

Having said all that, if it’s 110+ (where the hell are you that it’s over 110?), it’s not unreasonable for an AC to crap out. Since it’s morning and it’s Friday, I’d wait and see what the HVAC guy says before you start poking around at it. But if it’s, say, right out side your door (as opposed to on the roof or somewhere inaccessible)…if it’s running (and you’ve already tried the deicing thing), pouring some water down the coils wouldn’t be a terrible idea.

#5

Purposefully? Never understood why people think…I’ll save some money by turning off the AC in the summer time. And then just turn it on when I get home. If you have had a practice of doing this, that’s probably what killed your AC. Running constantly to cool your apartment down from 95 down to even 85 puts the sytem under a lot of stress.

It’s better practice to turn your AC up 5 to 8 degrees above your normal setting when you’re out than to just turn it off.

#6

It never hurts to have a backup window unit for emergencies. I have a window unit that I turn off during the day because it was cheap and doesn’t have a thermostat installed. It will just keep running until I turn it off. And if I leave it running all day, it’s frozen by the time I go to bed and only capable of blowing lukewarm air. It makes more sense for me to turn it on when I get home from work, because it gets the room comfortably cool within an hour and iceboxy by bedtime. But if you have central air, I don’t think this applies.

#7

Just to ask, would this be true of heaters too (the ones I have in mind are a 1x3 wall-mounted unit attached to a thermostat - usually I heat the room to as low as it’ll go while still being on, then turn it off when I go to work, so I’m not sure I can just leave it on at a “lower” temp all the time)?