A/C lines freeze up b/c no air is circulating

[Brandon McCombs]

Hello,

I'm hoping this is the correct group to use for my problem. I couldn't find a more suitable one from the list of available groups.

My problem is that my A/C is basically broken right now. I have an American Standard Freedom 90 furnace and an Allegiance 13 (I think) AC unit outside. I turn the A/C on at the thermostat and the condenser kicks on outside (I can see the fan rotating) but the house does not cool down. In fact, I end up with a puddle on my basement floor around the furnace because the coolant lines quickly freeze up and I get massive condensation built up (and eventually melting ice). I'm guessing the blower is not running but have no clue how to fix it or what caused it to stop running in the first place. The light on the front is blinking 6 times which indicates a "115 VAC reverse polarity or grounding problem" but I don't think either of those are really the problem unless the gurgling water problem that I mention below somehow caused a grounding issue.

The A/C was working on Thursday night. Friday when I get home from work the house was warm. I inspected the condensation line (not sure what it is really called) and it was frozen. I let everything thaw out but it still wouldn't work. Today I noticed the hose, which leads on one end to what looks like fan in a black casing in the upper portion of the furnace unit, was not connected. I connected it and I also flipped the breaker. Still have the light flashing 6 times. Setting the thermostat to "fan" doesn't do anything either.

One last thing to note is that earlier in the week I had the local American Standard guy come to the house because I heard gurgling when I tried to run the A/C. Turns out the hose I mentioned above that was frozen solid on Friday had a bunch of water in it earlier in the week. The hose had either been clogged or the sump pump that the hose leads to was not working. I haven't yet confirmed what the source of that problem was but now I have the problem where the A/C won't run at all.

The furnace and A/C units are only about 15 months old. I haven't touched any wiring (afraid to do so) and don't know anything about these things (I'm a new homeowner) so I'm at a loss to fix it myself but I want to learn. I also really don't want to have to call the HVAC guy again because I don't think he is very good and he may not be able to come by for a couple days anyway with the holiday coming up so I'd like to fix it myself, assuming a part doesn't need replaced.

Any ideas? Remember, I don't know what things are so be descriptive when you mention part names.

thanks Brandon

[Lefty]

You better call someone. There is likely too much to troubleshoot on your own. It could be the fan motor, it could be a wire fell off or was knocked loose, maybe the low voltage fan wire from the subbase.

[ransley]

There is althvac, that is where you get abused.

is where you get good help.

[Ed Pawlowski]

You are on the right track. The fan not running will cause the freeze up. The questions is why is it not running and that is more difficult to diagnose from here. Things you can check though, are loose wires and, broken belt if a belt drive Turn the power off. Open the furnace and give the blower a spin. The blower and motor should spin fairly freely. Look at any wiring connections and be sure they are tight and connecting. Without proper equipment, such as a multi-meter, you can't do much more. My guess is it is more involved, but sometimes simple things like a wire knocked loose by the service guy can happen.

Could be a bad motor, bad relay, bad ground, bad circuit board, bad capacitor (if motor is so equipped)

[HeyBub]

Freezing is often cause by very low coolant (Freon). Why the coolant is low is another issue.

You could have asked this on alt.hvac and would have gotten a similar response.

Specifically, "You dim-witted piece of s**, it's LOW f*****' COOLANT! G**D*** fool! You mother was a f*****' hamster and your father smelled of f*****' elderberries!

[trader4]

Since it's less than a year old, and should be under warranty, why not just call the company that installed it?

[ransley]

Can you get the Fan-Blower to run, in either heat or AC mode, turn fan to ON it should run continously. If only pjm was here to help.

[The Daring Dufas]

15 months, less than a year? Hummm, I must go back to school. Sister Godzilla will be very cross with me and probably hit me with a ruler.

TDD

[Stormin Mormon]

The OP did say that the furnace fan wasn't running. So, the first item on the agenda is to get the furnace fan running.

[Stormin Mormon]

Or take you out of shop class with Sister Mary Black and Decker. Then send you to see the principal, Sister Mary Herman Goerring.

Getting the furnace fan running is going to the the first step.

[Mike rock]

As others said, try the heat and see if the blower comes on, if it does, probably a wiring issue in the T-stat or furnace for the A/c control.

[E Z Peaces]

Has there been much rain lately? One winter morning I awoke to a gurgling sound from the furnace. I immediately shut off the electricity to the furnace. Heavy rain had flooded my furnace pit high enough to reach the blower. If it had continued to run, it could have ruined the motor, gotten the computer board wet, and made the house very humid.

The previous homeowner had had two computer boards and a blower motor ruined by water.

The flashing grounding-problem indicator also suggests that moisture may be your problem. It's possible that nothing has been damaged.

I don't know if the moisture could have come from a backed-up condensation drain. Outside, at the exit of my drain, I have a pit big enough to put a small container under the end of the pipe. If when it's fairly humid inside I can catch a cup of water in five minutes or so, that's a sign that things are working well.

[Red Green]

"HeyBub" wrote in news:A8ydnXe91Yz73ITXnZ2dnUVZ [e-mail]:

Never visited alt.hvac but it sounds like their mellowing a little... :-)

[Worn Out Retread]

It can also be caused by dirty clogged fins in the AC unit in the furnace plenum.

[Stormin Mormon]

If the fins are cleaned, does the fan start up again? He did say there was a blinking trouble code. Maybe cleaning the fins will help?

[Big Bob]

Unlikely that is the cause in this case. OP stated it freezes up quickly which indicates no air movement at all. I would bet on a bad thermostat or circuit board in the furnace not allowing the blower motor to come on. But you are correct when you say a dirty evap coil could cause a freeze up.

[CJT]

More to the point here, it can be caused by the furnace fan not running.

[The Daring Dufas]

I pulled a plastic garbage bag out of an evaporator one time. Another time I crawled under a house, cut an access door into the ductboard and pealed a 1/2" layer of pet hair off of the evaporator and it came off in one piece like a piece of felt. The coil was clean after that and worked well. Dirt is the enemy.

TDD

[The Daring Dufas]

The newer units often have these newfangled electronic blower motors that start out very slow and ramp up in speed then stay running at a very slow speed for a while and make you think something is wrong with it. It could also be the winding in the blower motor since the speed is often different between the heat and cool modes. It could be as simple as choosing another motor lead wire and running it until he gets another motor if the AC doesn't work well at that speed.

TDD

[Stormin Mormon]

I guess the dripping sarcasm didn't come through with plain text. The original poster reports the furnace fan is off, and trouble code six blinks, indicating reversed polarity or open ground. Cleaning the coils at this point would be absurd.