Cold air coming down intake, no air in out A/C vents

Patricia Lam
by Patricia Lam
I used a square of TP and a plastic bag and it's not sucking up in the intake. House is clean. New intake tunnel, cover and filter. no dust.
This is an intermittent problem for 2 month. Had 4 different thermostats - last one is wireless. Had TWO A/C (heat pump) units - 1 was 3.0 ton Amana heat pump (A/C) 17 years old (with new $450 blower motor, new switch, cleaned thoroughly and new capacitors (for sale); the new unit is a 3.5 ton, 16 seer, York heat pump (A/C)- a couple of days old. I insisted they check the wiring from thermostat to unit,and it was bad. I think one of the fairly new ducts is blocked. Someone had the air blowing into the attic. Knowing I have the same symptoms on BOTH units. The old unit would overheat every 3 days, it runs on the roof, but the fan doesn't run in the house, cold air comes DOWN not up in the INTAKE and NO air in the vents to the rooms. The new unit is experiencing these EXACT symptoms 3 times a day. Next week the electric panel will be upgraded from 100 to 200 amps. 14 visits by A/C techs from THREE companies. It's hopeless. No one will check the ducts. When the new A/C was installed this Monday, they sprayed 12 inches of insulation in the attic so probably harder to diagnose this 2 month old problem. It's 116 degrees out now at 2 AM and 90 degrees inside (desired temp 77). Could there be a different problem besides ducts?
Stressed and melting, Patricia

  5 answers
  • 19616405633 19616405633 on Jul 07, 2017

    Make sure the fan is working on the furnace. Check the filter. Is there any ice on the outside pipes next to where the pipes go in? If so your system is freezing up. fix turn ac off and fan on for a few hours. That will defrost the inside of the furnace. i just did this on my unit because workers keep leaving the windows open to let the sheet rock dust out. The u it sucked up all the dust anyway and clogged the filter. also the units are designed to take one temp in and lower it by a second amount. They can't lower from 116 to 77. Hope this helps.

    • Patricia Lam Patricia Lam on Jul 07, 2017

      after I replied to you. FIVE minutes later the HEAT and FAN came on. Just doesn't work with the AC. Could the fancy computerized wifi thermostat be to blame. It is not pairing when I tried to connect to their site but it let me sign on the wifi.

  • Ice8329808 Ice8329808 on Jul 07, 2017

    There are companies that just clean the ductwork. We had a similar problem when we bought our house 9yrs ago and I called a duct cleaning company (not a/c repair) and they found potpourri in the ducts that was collecting hair and dirt. Once ducts were clean our airflow problem was resolved.

  • Patricia Lam Patricia Lam on Jul 07, 2017

    I have new ducts installed just before I bought the home this year. They had the air blowing all over in the attic. Makes me think that a duct is blocked. The unit ran on the roof all night. Very cold air coming down the INTAKE and no fan to the house - now 90 degrees. So unbearable.

  • Patricia Lam Patricia Lam on Jul 07, 2017

    I turned it off for 3 times during the night. The fan never came back on. all night I stood under the INTAKE to cool off and had a fan direct that cold air to my bedroom. The unit just runs on the roof. This also happened with thet old unit but only every 3 days instead of 3 times a day with the new one. The fan did come back on with the OLD unit (in my yard). I had the wiring replaced from thermostat to unit and it's worse. I think it is a blocked duct problem. it's just DUCKY!!!!@#

    It's 89 now so I turned on heat, set to 93 and no fan or heat. Maybe he disconnected the fan when he rewired the thermostat (4th thermostat) but I believe the fan was running when I left yesterday.

  • 19616405633 19616405633 on Jul 07, 2017

    That I don't know. Sorry: