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bryanewade 06-08-2008 07:58 PM

AC freezing up and stopping air flow
Somebody please advise, new Westinghouse AC fitted last year 14 sear FS4BD model, worked fine last year, this year it freezes up outside and the air flow stops, temp inside rises.
When I switch the unit off and let the ice melt outside, airflow is restored and AC works until it freezes up again. Installer says that it is because I am setting the thermostat to low(68) and that the AC cannot get the room temp that low.
Is this correct or is there something not working correctly
When unit was working fine last year the asking temp was always 68 degrees please advise thanks Bryan

HvacWiz 06-08-2008 08:26 PM

Have you checked your filter, if it is clean I would suspect since it worked fine last year that your system might be low on freon.

bryanewade 06-08-2008 09:26 PM

thanks 4 that info, is checking Freon level something i can do or does it need an installer?

statman 06-09-2008 10:19 AM

Installer should check your freon level. Please be aware that " topping" up the freon is not required unless there is a leak in the system or it was undercharged to begin with. Freon is not like oil in your car...once a system is fully charged and remains leak free, you should never have to worry about it.

micromind 06-09-2008 07:29 PM

Does your system have a sightglass? It's a little round thing soldered into the small copper line near where it goes into the indoor unit. They usually have a 'pill bottle' type of cap on them.

If you do, write back and me or one of the other guys will tell you how to use it.


bryanewade 06-09-2008 07:54 PM

Unfortunatley cant find sight glass.
Installer suggested that 68 was to low a temp for the AC to handle and that is why it is freezing up (is this possible?)
Sunday afternoon i set the temp at 71 degrees, and after several hours of holding 72 degrees, the room temp rose to 75 on inspection, ice had formed on the outside connection to the AC.
I pulled the fuses and let the unit defrost and then at about 9pm I restarted the AC setting thermostat at a temp of 72 (house temp was then 77) this morning the temp had dropped to 74, but this evening when I returned from work (5pm) temp was back up to 77 with ice yet again forming around the connection to the AC.(is this ice forming mormal)
Also my original Question still remains, should my AC be able to cope with a requested temp of 68 degrees.
House is aprox 2400 sq ft

biggles 06-09-2008 08:35 PM

your installer is responsible for a tight VAC'd system...don't let anyone add freon without doing a complete leak check.COMPLETE LEAK CHECK:eek:your installer will dodge it any way he can.charge has to be recovered...nitrogen installed with freon mix to leak check all joints and fittings condenser,lines and into the air handler mucho time that he has to EAT:laughing:the unit lost some of its charge over the winter.tell him you want a 300 PSI nirto'd leak check and then a 250 MICRON VAC CHECK to hold for 4 hours before freon charg is reinstalled and get it all on the invoice for your records..don't pay for is as simple as if you bought a new tire for your car and it keep running low won't you bring it back.

statman 06-10-2008 08:19 PM ever want a job in Canada, come see me. You are dead on in your insight...nice to see people think like me.

Piedmont 06-11-2008 08:35 AM

I'm not sure if your AC should be able to hold 68F in a 2400sq ft house I'll tell you what it should do, it SHOULD be able to run 24x7 on highest cool mode without freezing up! They're designed NOT to freeze, the fact it's freezing means there's a failure somewhere. Some have correctly pointed out it could be low coolant, it could also be the fan. The fan outside forces air to blow through the coil & fins preventing things from freezing up. Water condensing on the fins then won't freeze it drips down. If the fan isn't working properly (could be a sensor controlling the fan) you won't get enough air flow and water freezing instead of dripping down. Make sure the area is clear, that vegetation hasn't grown over/around/inside and particularly above the unit and that your "fins" are clean. If your fins are dirty it will insulate them, being insulated they can't transfer effectively and will eventually cause freezing.

If it appears to be your pipes freezing, my bet is low coolant. It causes the system to not be able to push the gas completely through the evaporator coil, in turn it freezes where the gas stops circulating, usually in the evaporator coil. It's pointless to recharge a leaking system without finding the leak. How many cars have you experienced the AC failing and they "charge it" instead of fixing and charging? Works good for a few weeks to a month, then doesn't it go back to being useless again? I love the tire analogy, unless you find and repair the leak in the tire charging it is pretty pointless. I would start with the easy stuff, make sure the unit is clear and clean and fan working properly. If that's not it, it's likely low coolant and the others have done a great job telling you what to ask for.

bryanewade 06-11-2008 04:56 PM

Thanks for all the advixe guys, Installer came today checked coolant, and found leak, fixed said leak and recharged the system, that was at 9 am this morning, I returne from work at 6pm to find house at a comfortable 70 degrees (that was the thermostat setting) will try for 68 tommorrow maybe, will also keep u posted, again thanks for the help Fingers crossed it is fixed

cjett 06-11-2008 08:06 PM

Depending on the area you live in and how cool it gets at night, you may have to have a low ambient kit installed to keep it from freezing up during the night. If it happens again, and it's not low on charge, you may want to ask your HVAC guy if that is an option.

68 is pretty low, and if it gets cool at night, that might be the problem.

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