[DustinStag]

Hi,


We are renting a large 4 bedroom house in Florida. 1 room is located upstairs and has its own thermostat running on the same system as the rest of the house. We moved in in December. Since it is getting hotter here we are running the AC a lot more and discovered that the house is not receiving even airflow.

All the vents have very low flow of air coming out of them except for the upstairs bedroom and the downstairs hallway vent where the Thermostat is located close to. This vent blows a lot of cold air straight down.

I opened this vent and found multiple open air ducts in it. I will attach labeled pictures. But it looks like none of these ducts are getting any of the blasted air that's coming out.


I decided to do a test and Blocked this vent with a large piece of cardboard. Viola!! all the vents in the house had airflow and the temperature started evening out...........for a few hours. After that the AC kept running and the House temp started raising. I went to check on the upstairs room temp as we had set that thermostat to 82 since it is only used as a guest Bedroom. When I went up there it was at 74 degrees and had all the air flow pumping into that 1 room only. So I ended the test and removed the cardboard.

Everything went back to normal with the uneven temperature in all rooms. I waited for the AC to kick on again so I could see how the air flow worked out of the main vent, and it appeared as though their was 1 main duct pushing air out, 1 sucking air in, where to I don't know and the other ducts were just taking in minimal air.

Can anyone suggest anything I can do to, before calling out a Air Duct company? The landlord is fine with me having someone come out as he has never lived in the hous and has no suggestions, but I usually like to care of things myself when I can.

 

[tstex]

how many sq ft is the house and what size [tonnage] is the AC?

do you know to what speed the blower is set?

is the house fully exposed to the sun or is there shade?

How many windows and what side of the house has the most windows?

 

[DustinStag]

The house is about 2200 Sq feet. AC model is stating 4TON.

Carrier FV4BNB006



I don't know where to look for the blower setting


There is some shade around the house. In the AM Sun comes up from Backyard and makes its way to the Front for Dusk.


we have 9 windows and a sliding glass door, they are pretty much even through out the house. all have blinds, we have started hanging curtains but only on about half right now.



I will say when I blocked the vent from the pictures I posted, you could really feel the air coming through ALL vents and the whole house would reach the same temp. When its not blocked it just blast cold air down to the ground in the hallway when the AC is on, it doesn't divert through any of the other ducts. I can feel air coming out of the vents but its very faint, I believe the Thermostat cuts off the AC before the rest of the house is cooled because its positioned where are the air is blowing down.

 

[user_12345a]

you shouldn't mess with the equipment and ducts yourself when the property is not yours.

 

[DustinStag]

user_12345a - Yes I understand that, I have been in communication with my landlord about this. I am pretty handy and have already made other improvements to his house so far, which he is aware of. This is way i am reaching out to see if there is something else I should/could look at or try before calling someone in.



Thanks for the sound advice

 

[user_12345a]

There are a lot of things that could cause airflow problems.

Dirty coils, blower assembly, undersized/dirty filters, undersized and or poorly run air ducts, leaky ducts.

It would take a thorough evaluation by a knowledgeable contractor* or a diy'er willing to learn theory and buy tools to see what's wrong.

*Someone who knows how to and has the tools to measure duct pressure, direct airflow. Someone who understands how duct systems are designed, how to deal with zoning. (It sounds like the system has zoning, so it could be a zoning problem.)

 

[SeniorSitizen]

I waited for the AC to kick on again so I could see how the air flow worked out of the main vent, and it appeared as though their was 1 main duct pushing air out, 1 sucking air in, where to I don't know and the other ducts were just taking in minimal air.

To do your air flow tests consider running the blower only because there is no way the unit can be damaged with that method.

 

[DustinStag]

Ya I will be setting up appointments starting tomorrow.


Is it me, or does all the duct work look odd to be in 1 vent that blows directly down to the floor. The vent is just a normal 20x20 vent with no way to open or close the airflow out. I have been digging around the web and can't find anything remotely close to that setup.



When we first moved in, I thought it was just the Intake. The only intake that I can find in the house is from the actual unit in the garage and a tiny one for the upstairs bedroom that has its own thermostat working off the same AC unit.


Just seems like a weird setup for the house, but there have also been a lot of weird things in this house as well. so par for the course I guess.