How Do I Figure the Proper Amount of Intake Area for My Central Air Conditioner?

The intake for a blower is calculated by using 500 to 750 feet per minute as a maximum velocity across the filter area. That 500 feet per minute velocity in true in all ducts of a low pressure blower, both intake and output ducting. So lets say you have a blower with a capacity of 1500 cubic feet per minute.

Then 1500/500 3 square feet of duct at intake. If you figure the velocityh at 750 feet/minute then the intake size would be 1500/750 or 2 square feet of duct size. Try this manual for sizing ducting and filters for your AC About page 30 to 35 or so.

It gives homeowner's method to size ducts for your AC. www.thermopride.

com/manuals/mg-993.pdf

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my air conditioner dont work but in the add it said it had central heat and air is that false advertisement?

If the landlord won't fix it the next tenant will have to reckon with them too.

I would ask for your deposit back, if he collected one from you. Probably little to no chance you'll get it if he's not even making a good faith effort to maintain the property. If there was a lease agreement in place the landlord would be obligated under contract to have the a/c fixed, if not you really shouldn't even be obligated to give notice that you are moving out.

Even without a lease he's obligated as the property owner to maintain it, it's just poor business and lousy stewardship on his part.

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My central air conditioner died at the start of triple digit temperatures. Should I repair or replace?

You will save money replacing the unit. You currently have about a 8-9 SEER rated system. The least you can purchase today is a 13 SEER.

I have a customer who replaced his system this winter with a 14 SEER Payne system. He called today from Dallas Texas to tell me his power bill was $180 a month cheaper after we upgrade his system and added r-8 flex duct. It cost him $5200.

00 to do the job, but in 28 months his system will have saved him enough money to pay for its self. Plus he has 10 years warranty on the equipment and 5 years warranty on our labor. And 15 years of life in the equipment, which equals a total savings of $27,360.

over the next 15 years. Be sure to get the R-410A refrigerant

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Is my Central Air Conditioner Transformer bad or the unit itself?

First of all, it sounds like you replaced the run capacitor, not a start capacitor.

There is no such thing as a multiple tap start capacitor. There are however multiple tap run capacitors. Start capacitors are usually made of black plastic and are round.

Run capacitors are made of metal and are either round or oval. Second, are you sure that what you say is humming is a transformer? It would be somewhat unusual to have a control transformer in an outside unit.

It sounds like what is humming is a pulled in compressor contactor with no line voltage to it. Check the breakers and then check to see if you have fuses in the outdoor disconnect.

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will a dehumidifier work like an airconditioner?

Not really. By removing moisture from the air - IF there is a LOT of moisture in the air - AKA very humid, you will feel cooler and the air will be a little cooler. It won't cool like an air conditioner though.

You may notice a couple of degrees difference in your ROOM temperature if you have a room unit and about the same throughout the house with a central unit. If you see temperatures of 90 or higher in the summer and humidity levels of 70 to 100 percent, you will likely not be very comfortable with just the dehumidifier. I found this that explains it better than I can: http://www.

misterfixit.com/dehumid.htm

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what size air conditioner do I need?

No, sorry, it is too small to cool in the heat of the day. To even have any effect you likely have to turn it on full blast and early. But no need to ask us, you will soon know by experience.

I suggest you turn it on full in the morning and close off that room, all rooms, until it cools down that room then open doors to the other rooms one at a time. But at most that unit will likely cool only a couple of rooms, use fans to move the air around. Or you can run the central a/c fan if you like but that will warm the room with the a/c.

Good Luck.

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what are the symptoms of a bad circuit board for a gas central air unit?

Well on the older systems the gas would come on and heat up a Flexible bi metal which would rotate around and make contact with the fan switch and cause the warmed air to come out of the vents.

These newer systems have a flame sensor which determines ignition and in turn switches the fan motor on when the heat chamber is properly warmed. If the blower is automatically coming on and blowing cold air with no ignition then That board is probably fried. Yes the ac can work perfect and has nothing to do with the gas heat portion.

My guess is one of those large black relays on the board has fried contacts on it, look for burned or grayish areas around the 2 main relays on the board

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about central air conditioners and air conditioners?

Hi, Central air conditioners distribute cool air throughout a house or building by means of ducts that channel the air from the cooling coils to each room. There are also ducts to return the air to be cooled again.

These units are divided into two major parts: 1) An evaporator inside the house that cools the air, and 2) A compressor outside the house that extracts the heat from the coolant and returns it inside again. Air conditioners are usually installed in windows. The front part, the part inside the house, contains the evaporator ( the cooling part).

A blower blows the cooled air out into the room that the window is in. The compressor is in the back part of the unit that extends outside the window and exhausts the heat from the condenser coils to the outside air. Hope this helps.

FE

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central air condition unit has ice freezeing on compressor lines what is the cause?

Get an A/C Clean and check. the tech will know what to do.

but it sounds like you are low on gas. Wash outdoor unit with a garden hose until the water runs clear through the coil everywhere change the filter. The easy way to see if you are getting the cooling you need is to take a temp split.

after letting the a/c run for 15min Take the temp. in the return duct and the temp in the supply duct about 6ft from the furnace. Subtract and that number should be about 18-22 degrees.

it is not the best way but for the average home owner it can tell you if you need to call a service tech.

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Is it energy efficient to run the air conditioner only on the second floor?

What kind of insulation do you have, especially in your attic, beefing that up might help.

Close curtains and shades during the day to keep the passive solar out, that might help too. Then there's this thing called air penetration, that can waste a lot of energy if your house is poorly sealed, windows and doors are left open and the like. .

Also consider planting shade trees if you do not have any. In some cases, changing the color of your roof from a dark color to a lighter color can make a big difference. As we all learn more about saving energy and being more comfortable, many of the best things to do are not always the most obvious.

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Can my centrail air conditioner cause my throat to swell?

The air conditioner sucks in air from outside so if there is something you are allergic to yes, it can cause allergies. It also dries the air, and the dry air can cause your mucus membranes (such as the skin in the throat) to dry out and then get little rips and tears in them, making them susceptible to bacteria and irritants.

If you take a benedryl or over the counter sinus med and it helps, then that means there's allergies involved. If they don't help, try drinking lots of water and warm beverages to 1) hydrate your body and 2) wash any bacteria that may be in your throat down. You can also try a humidifier.

I have never found filters to be of any use. I have both problems.

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My central air conditioner runs almost constantly just to keep the house at 71 degrees.

Do I need freon?

First, also the simple/cheap thing to do. When was the last time you changed your air filters?

Your supposed to every 3 months, be honest? So go ahead and change them, believe me they need it. Then if that doesn't work, go look outside around your unit.

Does it have bushes closely around it so it can't operate correctly? If so, cut them away from the unit. Is the outside of the coils dirty?

Wash it off with the water hose. If all these items fell, you needed to do them anyway, call the air guy to check your coolant level and make any needed repairs. Have him check for pin hole leaks as well.

I had that happen one time. Hope this info helps!.

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how big of an air conditioner do i need for central air in 1100 square feet?

All these answers are the old way for sizing an house with the new changes in Energy Laws and eff. a sizing chart and ENERGY AUDIT need to be performed to ensure new unit will work properly.

U have to many HVAC Contractors that will put the same size back in and not take the time to do this it may cost u some monry but in the long run it's worth it trust me. If u don't do this then you;ll be just another dissatisfied cust. with a brand new system.

And this answer can be backed up by visiting your states energy program or calling local energy company and I'M a HVAC/Plum in trade 11 years so TRUST ME ON THIS AND GOODLUCK

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When do you turn on your Central or Window Air Conditioner?

I have to use it when it is humid because I have health problems. So if it is humid and colder outside then in, I have to turn it on.

Also if no air is blowing in ( a SW wind) I have to feel cool air but the pollen is horrible this year. That's another reason I have it on. If you have an intermittent control, which is usually found under the cover of a window AC, set it and it will go on and off when you set your thermostat to a certain temp to your liking.

For central air, set you thermostat to your liking and it won't come on until the temps in your home go above that number. Most people set it between 70-75 degrees. It depends how you like it.

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It's the first time I turned on my central air conditioner this year and it's not working.

what share circumstances are you going to substitute the breaker in the previous you're responsive to it relatively is not a defective breaker? The A/C is pulling too many amps.

there is a few thing incorrect with it, not the wiring. Contactors are incredibly a lot everyday. If the contactor factors are rated at adequate amps, the style isn't significant.

because of the fact the previous answer reported, you extremely shouldn't believe a random pal. you choose for a qualified individual to try this. My wager is that that's low on freon, yet there are different reasons?

Does it cool while that's working? in basic terms curious, it extremely isn't a DIY interest