For questions regarding a central cooling system for your home. This is typically a split system with an outdoor compressor/condenser and an indoor evaporator and air handler. Air ducts are used to cool air throughout the home.

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3
votes
2answers
584 views

What is the smell coming through my HVAC system?

If I leave the furnace fan always running for an extended period of time (to circulate and filter the air), when the central AC turns on there is a not-so-fresh smell that is emitted through the vents....
0
votes
0answers
80 views

Why does the A/C come on downstairs when heat is on?

I just moved in to a 2-story house. It is zoned upstairs and downstairs. If I turn the downstairs thermostat to OFF and the upstairs to COOL, the HVAC in the attic comes on, the outside compressor ...
1
vote
1answer
199 views

What is causing my AC to trip the breaker after running for about an hour?

After I turn on my ac, about an hour or two later it will make a noise and trip the breaker. Could this be a short in my fan motor? The fan does run.
0
votes
0answers
189 views

Buying used heat pump/AC

I'm planning to buy and install a used heat pump/AC at some point in the near future (probably looking for sellers on Craigslist or similar), and want to know what I should look for to know if the ...
0
votes
1answer
1k views

Central Air duct does not blow

We moved into a new house last year, the central A/C works great for all the rooms (even for closet) but we have a problem in just one room. There is almost no air flow coming from that room's air ...
0
votes
1answer
2k views

Air Conditioner woes: water pooling in basement, condensation on ducts, frost on outdoor copper pipe

Can someone help diagnose what's wrong with my air conditioner? The symptoms are: the air that it is blowing is not very cold It's colder than the ambient air, but not cold enough to cool the ...
1
vote
1answer
96 views

Is this HVAC capacitor dead?

HVAC system stopped blowing cold air today. Last time it did this, we gave it a 2-3 hour break, in case it was over-heated, and it came back. Today, same deal, but no cold air after a few hours. I ...
1
vote
2answers
2k views

How do I interpret a central air conditioner label?

The label on my central air conditioner looks a lot like this one (photo below). What do the two numbers (separated by a slash) mean for voltage and the three amperage ratings?
5
votes
1answer
335 views

Central air conditioner grounding wire size difference

I disconnected the central air conditioner long ago during the initial phase of my home renovation. I am preparing to hook it up again and have a technician come out to look at it. The original wire ...
0
votes
2answers
368 views

What size A/C unit should I install?

currently using a Goodman 24000 BTU Central air, installed in '96. it is starting to cost too much because of leakage of refrigerant. I did the size calculator thing and it recommends a 30000 BTU unit,...
0
votes
0answers
191 views

How to insulate this portion of split AC Pipe?

I bought a new Hitachi split AC lately which isn't cooling as much I was expecting. I checked for leaks/bad installation and found this. (This is connection point of external pipe and pipe which ...
1
vote
1answer
105 views

Central air compressor fan reflects sunlight into house. What can I do about it?

I have a new construction and for whatever reason the HVAC installers placed the compressor right in front of a bedroom window. I don't have any complaints about the noise (it is actually pretty ...
1
vote
1answer
10k views

What causes a HVAC control transformer to overheat?

I recently replaced my 24 volt HVAC control transformer. The outside unit started up including the air handler and ran for maybe 10 minutes. After the units shut down I noticed that the transformer ...
0
votes
0answers
123 views

Are wall air vents a potential problem?

A house I'm looking at has A/C vents in the walls, rather than in the ceiling or floor. I've never lived in a house with air ducts in the walls. Can I expect to have problems? The house was built in ...
7
votes
2answers
12k views

Why are almost all of my house's HVAC floor registers placed near exterior windows?

My current house is a single story built over a crawlspace and all the HVAC registers are in the floor. In all of the larger rooms, at least one (and usually more) register was placed near an exterior ...
0
votes
1answer
11k views

When should HVAC returns be opened and closed?

My Pennsylvania house was built in the early 90s, has central heat (natural gas) and central A/C, and most rooms have pairs of closable air returns on the wall near the floor and ceiling. I've been ...
0
votes
1answer
7k views

How do I eliminate the cold drafts coming from my air conditioning vents during winter?

I have a forced hot water (baseboard) heating system in my home and added central air conditioning about 10 years ago. The cooling system's air handler is in my attic, and duct work was added for the ...
1
vote
1answer
2k views

Why is my outdoor air conditioner unit making a screeching/squeeling sound?

During the winter time when I have my heat on, my outdoor air conditioner unit randomly makes this awful-sounding squealing/screeching sound. It lasts for about 15-30 seconds at a time, stops, and ...
3
votes
1answer
6k views

Where should I tap in to the existing duct work?

Bought a 1981 repo a year ago. The house measures around 900 SQFT. I enclosed the one car garage (10'x20') @ 200 SQFT to serve as an office. The front of the garage is insulated (10') along with the ...
2
votes
1answer
491 views

Why do they put an A/C vent in the utility room?

A related question is here about a year ago: Is there any reason to not tape this vent over? My question is, why do they put the vent there in the first place. Like the previous poster, I just bought ...
5
votes
1answer
2k views

How can I replace the plywood under my air handler?

Sunday morning I walked out into my garage to find two huge water spots in the ceiling. The condensate drain line that comes out of my air handler in the attic had clogged up, and it turns out the ...
4
votes
2answers
8k views

What should I do about a central air duct leaking above my ceiling?

My closet ceiling is leaking a brown liquid. Right above it is an air duct for my central air. I think the liquid is dirty or rusty water that has accumulated in the duct. I can hear it dripping ...
2
votes
3answers
3k views

How can I repair these rusty electrical connections?

When I turn on my air conditioner at the thermostat the vents kick on but nothing outside. Also the last time that it worked it took a few minutes to get going and was pretty loud. I checked the ...
6
votes
7answers
3k views

Should I apply car wax to the outside of my air conditioning unit?

Through different conversations with family members and friends, I have been told that it is good to apply a coat of car wax to the outside of the air conditioning unit frame. I assume that this is to ...
3
votes
4answers
671 views

Air conditioning on a shoestring budget

Without purchasing expensive air-con units, or solar panels - and the associated moutings and electrical paraphernalia, is it possible to create a temperature difference of 10-20 °C using materials ...
3
votes
1answer
403 views

Is it normal for air to be leaking from where the drain hose connects to the central A/C unit?

I'm trying to determine if I have a leak around my central AC unit. Basically when the unit is on, I feel cool air blowing outside the "furnace plenum" as I believe its called. If you look at this ...
2
votes
1answer
1k views

Is there any reason to not tape this vent over?

I just want to make sure this wont hurt anything. Right before I bought this house, it got a new AC and furnace but they did not replace much of the duct work. This vent is right above the AC unit ...
3
votes
2answers
472 views

Are clogs in the AC condensate drain common in Florida?

I have a two year old central A/C unit. Every 2/3 months the unit shuts off. I called the rep/maintenance company and they have given me the following response: The cause of the issue is algae ...
8
votes
3answers
2k views

Should a bathroom fan vent to a separate duct system?

Is it acceptable to route a bathroom exhaust fan to the return of a central air system? I'm afraid this will cause mold to grow in the air return ducts. There is currently a fan in our bathroom and ...
0
votes
0answers
1k views

A/C system reports Limit Switch Stuck Open

Unit is a York GM9S080B12UP11G. When switching thermostat to cool, the system activates the compressor fan. Also, I can hear gases moving through the pipes running to the compressor. However, the ...
3
votes
1answer
6k views

Air deflectors on floor registers and cooling efficiency

I was once told by an HVAC technician to avoid using air deflectors on floor registers during the summer. The reason was that the last thing you want to do is to direct the heavier, colder air ...
3
votes
1answer
225 views

Improve AC flow to secondary ducts

I have an AC which has 3 ducts coming out of it. Only one duct gets flow - I'm guessing the AC fan blows right into it. What can I do to improve the flow?
1
vote
1answer
666 views

Furnace Airflow

I have central air. When the furnace comes on, we can feel air coming out of the registers for a few minutes, then the airflow stops. If we turn it off for a few hours, we can turn it on again and get ...
2
votes
2answers
2k views

How do I clean an AC condensate pan?

I have a Ducane HVAC system that started leaking out of the evaporator coil housing. Mine looks like the EU1P. I read that i need to clean out the drip pan. II tried cleaning it by sucking out the ...
5
votes
1answer
2k views

two condensate drains?

we just had a new AC system installed in my florida house. the unit is in the garage, and the air handler is vertical with the evaporator on top. the unit he removed had 2 condensate lines: one that ...