I have a bryant cental air unit. The problem is that the air is not coming through the registers like it should. I checked the filter at the return vent and it is okay. The condenser and the fans in the unit outside are operating. What could the problem be?

First off, do you live in a science lab…70degrees?? But, with a reliable thermometer, check the temp of the air coming out of the supply grilles. AT THE GRILLE NOT 5 feet away. Then do the same at the return. You should have anywhere from 14 to 20 degrees of temperature difference. If you don’t you likely have a refrigerant issue. Units just don’t need “gassed up”, if it does need gas you have a leak. Is the filter clean?? Furthermore, a 2 ton unit should be able to cool the space, might be pushing it a bit and 70 degrees on brutally hot day might just be too much. Hope this helps.

Either a bad control board on the inside unit or a bad blower motor.

Two things cause a unit to ice up restricted air flow over the evaporator coil (it's the one that ices up) Can be a dirty filter or the coil may be dirty or the return air vent may be blocked. Other cause is low freon.

measure the size and get replacement filters almost anywhere.

Hi, this is a 4 ton unit, Bryant are top of the line, I believe so as I have worked on them for so many years. They were Day & night, just a name change is all. Here is what sounds like your problem is, or is your problem. Did the tech check the TD of the supply air and return air? This is the temperature difference. There should be a TD of 18*f to 25* TD or temperature split. Example is, if the supply is 56*, the return at the filter should be at around 76* which is a 20* TD. If the outdoor condenser started to defrost when you removed the filter, you were getting more return air through the evaporator coil. This tells me that your return air duct has either come loose, has a large hole or holes in it, or if you had a repairman under the house or in the attic where ever the duct work is, has flattened it, and you are not getting enough return air back through the evaporator coil. This will cause the condenser coil to ice up quite fast. When you remove the filter and panel, you should feel a pulling almost like a magnet as the return air will be a strong force. This is your problem if all coils are clean and the system is charged properly, this is the only way the outdoor coil will ice in the summer. If the indoor coil were dirty, or low on freon, the indoor unit would be the coil with the ice build up. You say the air increased slightly, and the outdoor coil started to defrost. The problem is the return air 18" duct is either crushed, Holes from pests, or has come lose at some point. This is all it could be, mark my word!! Have it checked, or if you are able to check it, you can maybe hear it where ever it was put in, up, or down under. Find it, and you will increase the CFM by 50% depending on the leak. Please keep me posted on this and when you rate me be kind as I know you will. Trust me, this is your problem. Please keep me updated by my user name below.
Sincerely,
Shastalaker7
A/C, Heating, & Refrigeration Contractor

Make sure it is in cooling mode. Sounds like you may have a problem with the reversing valve but you would want to check the pressures in the system first and make sure the charge isn't low.

Here are a few things that would cause low amount of air to come out of the registers in home:
1. Something is blocking return air, like couch in from of return air register.
2. Dirty air filter. Clean or Replace!
3. Icing. Check large pipe on outside unit. If it has ice on it shut off sustem and call a qualified technician.
4. Fan speed may be wrong on blower. Put on HIGH.
5. Duct work may be apart. Check duct work and correct if needed. Note: If you have asbestos duct work do not repair. Call a qualified repair company.
I hope I have helped.
Terry

Unplug the unit with all controls off, then plug back in and wait 5 minutes before turning on switct at unit. Good luck

'Limit or flame rollout switch is open'. In my case, the flame rollout switch had tripped due to an overheating? I had to push the button between the wire leads to reset the switch. Then when I turned the power back on, the furnace started up like normal.

Why did the switch overheat and trip? My current theory is that there was a rubber grommet around a pipe near the switch that had slid down and was no longer sealing the furnace?

If you need further help, reach me via phone at https://www.6ya.com/expert/robert_6c29b8565d620da3

sounds as if your low voltage transformer might have bit the bullet will need replacing all of the devices you mention are powered by this one low voltage t-stat