Hello, so here is my problem. I was sitting and all of the sudden I heard this crackling sound like something dropped inside my AC unit. I shut it down and I left it for 2h. Then, I started it. First of all, I noticed that the fan is working without problems. So, I set it on cooling. I put my hand on the window and it was cold air. This only lasted for two minutes then the AC unit starting giving me hot/warm air. Also, there was this weird sound like the compressor trying to start up then ends up in hissing sound.

This is an old Window AC unit. Can you give me some insight on the problem?

Edit: I forgot to mention that the AC unit started building ice on front that I had to run the fan for 30m to get rid of.

 

Thanks for the reply, mate. So, where do you think the problem lies? How do I fix my problem. Regards.

 

Welcome to the forums.

You replied to a spammer. A computer generated useless reply.

Based on what you're telling us you either have an airflow problem.... clogged filter, clogged evaporator coil or the fan is running too slow.

OR... the unit is low on refrigerant which would also cause the coil to freeze up.

 

Thanks for the replies. I discovered that the fan got chipped. After replacing the fan, the AC unit seems to be working fine, for now. Though, the build up of ice on the filter is still there. It just takes a long time to do this now. How can I fix the ice build up? I asked the technician to check the refrigerant level and he said its not low.

 

Are you using the A/C now ? It may be a little cold outside for a window unit.

Do you get frost/ice over entire unit or just at the top or bottom ?
I'd love to know how the tech checked the refrigerant level as most window A/C's are a sealed system.

 

It is a bit chilly outside on dawn. That is about it. I only get frost under the air filter on the entire coil surface area. I made sure the filter is not dirty. I defrost by putting the AV on Fan mode.

The technician checked for the refrigerant level by attaching a handheld device into the power line. Then, he told me its ok.

Thanks again.

Edit: I just wanted to mention that I changed the fan less than two months ago for the same issue. It got chipped off like this one that I replaced yesterday.

 

Ok, so here is an update. I decided to lower the number on the knob from 10+ to 4. Now, I can see that the AC starts up the cooling then stops and repeats the cycle more frequently. I got no frost on my coil so far and I have been running the AC for half a day now. Usually it takes less than 8 hours for the frost to fully cover the coil. Hopefully, this will fix the problem and helps whoever has the same problem.

 

The compressor cycling will allow the coil to defrost and dry out.

I'm still at a loss.... I'm in NJ and haven't needed the A/C for quite a while. Where is all your heat coming from ?