Originally posted by mel221
Thanks everyone.

Here is what I know now.
Attic Temp 109
Return Air at grill - 79
Return Air at handler - 81
Supply Air at handler - 66
Supply Air at register - 67

This morning, I had these results
Attic Temp 90
Return Air at grill - 79
Return Air at handler - 80
Supply Air at handler - 60
Supply Air at register - 60

I am confident the supply and return ducts are sealed and not leaking.

I think my problem is the 15 degrees of cooling I recieve in the afternoon. I measured the airtemp in the handler return by attaching the thermometer to the filter inside the handler. The handler itself is not leaking air.

So, in the afternoon, when the air handler box is 109 degrees, the air handler cannot produce 20 degrees of cooling.

udarrell, I will be looking over your materials. Thanks.
First, the airflow may be too high for that small A/C system and during the day when it is hot the condenser is not doing an effective job, --coupled with an improper charge it will not cool efectively.

In the morning you have a 20 degree split, during the day you only have a 14 degree split. The condenser can not handle the hot daytime hours. (Too little or too much charge.)

The tech may have charged this system when the home was very hot and over charged it; or if it was cool it could be under charged.

What is the super-heat (piston fed) and sub-cooling (TXV fed)? Get both figures irrespective of metering device.


This linked page will explain what too much airflow and overcharging a system will do!


Get an accurate charge in the system during a hot day!