HVAC Questions? Ask an HVAC Expert for Answers ASAP
What is the problem that you are having.... you should have at least 2 square inches for every cfm of air flow.
3 ton = 1200 cfm / 2 = 600 square inches of free area in the filter grille.
I miss typed the first statement.
House take a very long time to cool down from say 84 to 79.
System was just inspected and everything is fine/ Register exit temp is about 55-60F. House is well insulated.
How do I determine tonagge and/or cfm of my system?
air feels like it is barely coming out of the vents.
the 14 x 14 's only equal about 400 square inches
you are having air flow issues, many folks are starting to use pleated filters in ducts and grilles that are not large enough to accomodate this higer resistance. Is this the case at your home?
Yes high efficiency pleated air filters
do not use only the delta t to determine the systems operation. it may only be a high delta t because of the poor air flow....
get rid of the pleated filters immediately!!!
you are definately undersized on air flow with a 80000btu furnace.
OK. How do I determine cfm and/or tonnage of my unit?
can you get the model number off the unit outside?
yeah, hold on...
you also may have ice blocking the airflow of your system
while you are checking on the model number notice the large copper tubing entering your condenser unit... it will usually have a black neoprene insulation cover on it, check to see if you have ice on that line. and or see if it is dry or wet and cold.
Insulation was dry. About 6 inches of pipe uninsulated was wet, probably due to condensation. It is 100% humidity outside.
ok you have a two and a half ton unit with probably aXXXXXfurnace.
now did you feel the temp of the wet line?
it shoudl be cold. but this can be miss leading if your coil has more blockage besides the pleated filters.
it was cool, but not "ice cold".
furnace was just serviced when I bought the house and found no blockage or ice
ok you really should do a test on your system.
i'll get furnace model...
the ice may have occured recently
ok now dont worry to much about the furnace model number.
is just in case there is still some ice on the coil and it is only partly blocking the air.. you should only run the blower for around 45 minutes. then turn the cooling back on. Run the cooling for about 15 to 20 minutes and check this line again.
if it is dry and just cool to the touch then most likely you are also low on refrigerant.
It was serviced two weeks ago. So I think is is ok, and it is probably undersized return air grill, aggravated by pleated filter.
if you also want to go a step farther you should open the control box of the condenser and check the capasitors visually. if they are flat on the top and botXXXXX XXXXXke a can of soup then they are likely ok. if you see buldgeing on the top or any burnt wiring then i would then ask you to call a service tech out.
What is proper cubic inches for the 2.5 ton unit and furnance you think I have?
how well do you trust this person that checked your unit?
if it were my house i would put as large a filter grille as would possibly fit!
I watched him do it. He was there an hour and it is the company the installed the unit originally. As much as you can trust anyone you don't know. :)
for example i have two 16 x 25's for my 3 ton.
and you have them in < blank formation in the return line before the unit?
well just check the service caps there are four of them for you to tighten.
stacked one over the other..vertically. i bought a custom grille for $100 white architechtural high flow louvers.
the service caps are where the tech will attach his guages.
I'll make sure they are tight.
I think you answered my questions.
they have a schrader valve (bicycle type)