Our window aircon stopped cooling and made loud clunking, clicking, dripping sounds over night. We tried different settings, moving nearby furniture (blocking air?), replacing outside hose (goes to a drain), thorough cleaning. Finally, we replaced it less than month ago. Now the new one is doing the same thing! This problem occurs as night wears on. Now I notice the new air conditioner has a block of ice over the inside coils in the morning! Maybe that happened to the old one too? (I unfortunately never checked.) The air conditioner is relatively small and in a smallish bedroom. We have a bigger aircon in our smaller guest room with no problem. I can't go outside and inspect, we live on the 14th floor. What's going on?! Thanks! PS We live in Hong Kong and I don't speak Chinese, so I have a really hard time explaining this problem to anyone, especially since the air conditioner seems fine during the day once it has defrosted.

(Uh oh, sorry, posted in wrong thread.

 

Post moved to air conditioning.

 

Welcome to the forums.

What are your night time temperatures there ?

 

Thank you! It's just starting to warm up for summer. Last night was about 74 degrees F outside and the room was 74 with the air conditioner on the highest settings all night. Summer will be in the 90s.

(sorry, just edited. It was 78 outside when I got up this morning but looking online it was 73-75 last night).

 

Outside temps are fine. And if filter is clean, no furniture with in a foot are so from intake it sounds like its either low are refrigerant or maybe the fan is stopping. Put the fan to on or circulate and see if that helps.

 

Here in the states I have seen brand new window AC's that froze up due to low refrigerant. I'd ask to swap for a different brand. All the A/Cs in the lot the retailer has may be low because of a mistake on the assembly line.

 

Thank you very much for the responses. The fan seems to run fine. I upped the fan speed and lessened the cool dial (made warmer) for the night. We didn't have ice this morning, although I'd prefer a cooler room. My husband thinks it worked last night. There is a tall wardrobe about 18 inches from the AC, so we will rearrange the room to move that further away. Our 9-month sleeps in here too, so when he's sweating and tossing and turning, I get so stressed out! It sounds like if the problem continues, I will have to address a refrigerant issue. That's very interesting about the new ACs Ray. With the involved installation of this one (installed into a hole in the wall, outside drain connection, 14th floor etc), I'm hoping something can be adjusted without replacing again. But we will if we have to. I really appreciate everyone's expertise.

 

As has been said , coil freezing is usually insufficient air flow or low on refrigerant .

How many square feet is the bedroom & what size ( BTU ) is the A/C ?

Do you leave the bedroom door open to the rest of the apartment ?

Once the room cools down , and it cools down outside , try turning the controls to fan only ( no cool ) .

Do you have a ceiling / paddle fan , also ?

God bless
Wyr

 

That could be your problem. Window A/Cs often have side vents. If they are partially blocked by the wall it won't cool correctly. Through the wall A/Cs don't have side vents. If it is a window A/C it may need to be moved to a window so the side vents aren't blocked.

 

Thank you Wyr and Ray. The aircon is 7000 BTU. The room is 7x13 feet (91 sqft) and in afternoon sun. There is no ceiling fan, but we just cleared the top of the wardrobe and put a fan on it to blow air by the aircon, picture:

http://imageshack.com/a/img673/4014/VsB8YI.jpg
We usually close the bedroom door.

Ray, I didn't realize the difference in through-wall versus window aircons. Here is a picture from outside the building of the aircon. The side vents seem relatively unobstructed (there is some space between L-shape shelf and aircon).
http://imageshack.com/a/img901/2108/kniM5u.jpg
I also just found a lever hidden in the cool-air vent that will switch between outside and inside air intake, so not sure if one is better. Just had a second ice- and clunk-free night of cool air,so I hope the adjustments have improved things. Thank you!

 

It looks like adequate clearance. Outside air intake reduces the cooling of the A/C because you are diluting the chilled inside air with hot air.. How it would affect the freezing, if at all, I can't say.

 

Window A/C Sizing Chart

This is a generic chart to go by.

Area in
square feet Btu/hour
100 to 150 5,000
150 to 250 6,000
250 to 350 7- 8,000
350 to 400 9,000
400 to 450 10,000
450 to 550 12,000
550 to 700 14,000
700 to 1,000 18,000

I thought a 7,000 BTU sounded a little large . Also , try opening the bedroom door ?

God bless
Wyr

 

Interesting, I will, thank you Wyr and Ray! So thankful to find this forum