For general questions regarding cooling your home.

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13
votes
5answers
33k views

Should I cover my air conditioner for winter?

Should I cover my air conditioner for winter? It's difficult to find an appropriate cover, but finding a cover for an evaporation cooler is easy (and because they allow for air flow from the outdoors, ...
3
votes
2answers
173 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 ...
13
votes
2answers
5k views

Can I run a central air conditioner in the winter?

What happens if you run a central air conditioner when it's below freezing outside? Is this expected to work? I know, it sounds crazy, but that's because you don't live in an overheated New York ...
2
votes
1answer
2k views

How can I prevent heat loss through heater/air conditioner wall units?

HVAC experts out there... I live in Wisconsin and it gets mighty cold here! I have a condo with 2 wall units that are used for both air conditioning and heat. My heat bill in the cold winter months ...
1
vote
1answer
14k views

Should I add a return air vent in a refinished basement?

We are refinishing our basement, and are nearing competition. The walls are drywalled, and the ceiling is dropped. There will be about 500 sq ft of finished space, including a full bathroom, and ...
0
votes
2answers
71 views

HVAC system setup

I have a builder building me a home right now and we had agreed to set up two separate heating and cooling systems for the first floor and second floor of the house. I raised the issue the other day ...
0
votes
0answers
83 views

Can you hardwire a residential through wall A/C to a 3H/2C thermostat?

I have a boiler with radiant baseboard throughout my home with four zones of heating and two through wall air conditioners and Aprilaire 350 Humidifier. I am upgrading my thermostats to the Honeywell ...
2
votes
2answers
8k views

AC Unit Blow Warm Air Indoor But Colder Air Outdoor

I have two AC Units. One for upstairs and one for downstairs. The upstairs one works just fine but not the downstairs. So, i did a test by turning both units on and went outside to compare the two ...
0
votes
0answers
42 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 ...
2
votes
2answers
10k views

Why is my A/C unit running when the heater runs?

So it finally got cold here in AZ. We switched our thermostat from A/C to Heat. Now for some reason when the electric heater runs, the A/C condenser unit outside kicks on too. This is our first winter ...
1
vote
0answers
18 views

What cleaners are there in the market to use for Air duct duct cleaning?

My house is near to the mountains so I' am unable to get any help from Air duct cleaning Denver experts as they are unable to come over my house. Can any body suggest me some cleaners used for air ...
0
votes
1answer
116 views

When to Replace UV Bulb in AC System?

We had a new AC system put in last summer. The contractor included a UV bulb between the cooling area and the supply fan. It's supposed to kill bacteria and other nasties in the air. (The bulb is ...
1
vote
1answer
485 views

What could cause a condensing units fan to stop working?

My AC unit fan stopped working suddenly. I tested the 3 pole condenser (capacitor) and the it looks OK ( 45 uf , 5 uf is what is mentioned in the spec of capacitor). I tested the resistance in the the ...
0
votes
1answer
447 views

How to add “C” wire using a/c fan wire?

Honeywell has a video that shows how to use the fan wire ("G") of the cooling system as the "C" wire for the thermostat. It is in the video - "Honeywell DIY wifi...substitute g-wire for c-wire" on ...
0
votes
3answers
18k views

Why does my Central A/C Keeps Blowing its Fuse?

For years, my A/C condensing unit has blown a fuse once, maybe twice a year. It's 27 years old now and blew a few fuses last spring. Now it blows a fuse every few days. So, I replaced a bad running ...
0
votes
0answers
37 views

Thermostat needs to be set very high to work

Our home thermostat is behaving strangely. Let say it shows that the current room temperature is 60F. If we set it to 63F it will start the Fan (ventilation) but will not actually start the heating so ...
0
votes
0answers
98 views

How can I stop an in-the-wall air conditioner from leaking air into the home?

As far as I can tell, the air conditioner fits nearly perfectly in the hole, but there is considerable air leaking into the home through the bottom. I think it may be because of metal strips that line ...
0
votes
1answer
842 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
154 views

Should I remove my air conditioner for the winter?

I have an air conditioner that sits in the window. Due to restrictions placed by my apartment managers, I was unable to install any external support. Instead there are 2 L-brackets that keep the air ...
2
votes
1answer
67 views

How can I install a window air conditioner and still allow the window to be opened?

I want to install a window based air conditioner but still allow for the ability to open the window when needed. I was thinking of using a piece of wood screwed into the window frame to support the ...
0
votes
1answer
55 views

If flame sensor will affect Motor assembly's functionality of furnace? How does that work? [closed]

I have two Air conditioning company. A is the self-hired for my A/C, and B is assigned by home warranty company. This summer, the technician with A came out for an annual maintenance on both A/C and ...
1
vote
1answer
74 views

How do I connect a 24v air purifier to hvac?

I have a MicroPure MX4 that the previous homeowner left behind new in the box. This is a 24v unit and needs to be hardwired. My question is can I connect the two wires to the terminal where the ...
1
vote
1answer
84 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 ...
4
votes
2answers
250 views

90% Humididty @ 23 Celsius direct from Air Conditioning Outlet

I have a mold problem in my apartment, in certain areas there is condensation. I believe I have traced this to the air conditioning, in the apartment the humidity will vary from 60% to 85% RH at a ...
1
vote
2answers
293 views

Combine evaporative cooling with ventilation to increase efficiency of temperature equalization?

We live in San Francisco, which is not known for high temperatures. But our apartment is on the third floor and we get a ton of direct sunlight through our 5'x8' windows. We open the windows enough to ...
0
votes
0answers
33 views

Keep finding thermostat on heat

On multiple occasions now, I have noticed odd things going on with my HVAC system, only to go to the thermostat and find that it has been set to heat! This happened once in the middle of summer, when ...
1
vote
1answer
3k views

How often should “self clean” and “allergen clean” functions be used in an air conditioner?

Some air conditioners, for example Mitsubishi heavy industries SRK20ZJ-S have "self clean" and "allergen clean" functions. First takes 2 hours to complete, latter 1.5 hours. How often should they be ...
3
votes
1answer
151 views

Is this mold on my AC vent?

I went to close the AC vent in the apartment we're renting and saw this. Is this mold or just many years of dust buildup? If it is mold, can I safely just remove the vent and wash it?
0
votes
0answers
54 views

Lint when running AC

There seems to be a lot of lint when I run my AC unit. I have recently replaced the filter and made sure that the filter is put in correctly. What could be the issue?
0
votes
1answer
108 views

Should my A/C compressor come on when I turn only the fan on?

I have a bog standard HVAC system with a Nest thermostat. When I tell the theromostat to turn the fan on for 15 minutes the A/C compressor also kicks on. Is this normal?
0
votes
0answers
269 views

Furnace not working properly with digital thermostat

I have been attempting to use several different types of digital thermostats to replace my old mercury thermostat, however none of them are able to control the furnace properly. All of them are able ...
1
vote
1answer
412 views

New condenser fan motor burned out

AC technician replaced my condenser fan (through a home warranty service). The new fan worked for 5 min and stopped working after that. the fan motor was extremely hot (180F or more) The old fan motor ...
1
vote
1answer
101 views

How to install a 4-wire a/c & fan thermostat with only 3 wires

My home currently has a central a/c unit which is controlled from an 3-wire old mercury switch thermostat. I want to replace it with a newer Honeywell that requires 4 wires. The existing thermostat ...
0
votes
1answer
293 views

Single phase vs three phase commercial air-conditioning

I have a building in which I am going to replace 9 3ton units. There is 3 phase in now but my tech suggests single phase. My clients pay for their own electricity. These machines have been in service ...
0
votes
2answers
135 views

Can I stack my boxed air conditioning units for storage?

I pulled out the AC units from the windows and have put them back in the original boxes that they came in. Can I stack them one on top of another for storage? I know not to stack the units normally, ...
1
vote
2answers
757 views

thermostat batteries replaced, AC unit won't start

Came home from work to find no AC. I checked the thermostat and the display was blank. After replacing the batteries and resetting the program, my AC unit never started up. I checked: - The AC unit ...
1
vote
1answer
2k views

Air handler condensation draining problem

For the life of me, I cannot figure this out. My air handler and heat pump were installed in 2006 and work great. For the first summer since I've owned the home, condensation started to not drain ...
0
votes
1answer
684 views

Furnace filter inserted backwards, will this cause permanent damage?

Just found out that my wife changed the last furnace filter and inserted it backwards. This was noticed after the ac was not cooling the house very well. I went outside and noticed that the coil ...
1
vote
1answer
170 views

A/C Unit Has Leaking, Has Ice Buildup

Came home yesterday to find that the house was burning up and the thermostat had automatically switched itself to heat... in the summer! We didn't know what was going on, and assumed some sort of ...
1
vote
3answers
256 views

A/c makes the lights turn on and off! No Joke!

The lights on the first floor, upstairs bathroom and upstairs Laundry room won't work. The breakers did NOT pop The air conditioning was running this morning but is not working now. When the ...
2
votes
1answer
47 views

Why does my air conditioner say not to shut it off and restart within 3 minutes?

My air conditioner says not to turn it off and then back on within 3 minutes. Why is that, and what will happen if I do?
6
votes
6answers
25k views

How often should I run a bleach and water solution through condensate lines?

How often do you need to run a bleach and water solution through the condensate drain lines (of a heat pump) to keep the bacteria away? What are the recommended parts (e.g. 1 part bleach, 10 part ...
0
votes
1answer
3k views

Air conditioner that keeps turning off

My air conditioner unit outside keeps on turning off and the fan in the house keeps on running. When I switch the circuit breaker off, then on the outside unit works again. Do you know what might ...
0
votes
1answer
65 views

How do I connect original to new wiring when repairing an electrical fault in an AC unit?

The AC failed at a neighbor's house and the problem was quickly diagnosed as electrical. I saw that a few of the wires had corroded and one had actually burnt through. The unit is only 5-6 years ...
0
votes
1answer
253 views

Window unit AC installation in narrow window

My apartment has double hung windows, but they are quite narrow (~19.5 inches at the screen, 22 inches at the opening). I'm currently using a portable air conditioner, but I'd really like to use a ...
0
votes
1answer
633 views

Inverter air-conditioning units or non-inverter air-conditioning units?

I want to purchase new 8-9 units of air-conditioning for my new house. For the hall, kitchen and all the bedrooms. Some people say inverter air-conditioning is only suitable if you are using more ...
0
votes
2answers
404 views

Can I redirect airflow from AC to under the house?

I have a small 950 sq ft single floor house, with a crawl space and force air heating. I have a portable Air Conditioner that has a large Intake and Exhuast tube. The issue is that none of the ...
0
votes
0answers
58 views

Covering Up A Large Gap In A Wall

I was looking for advice on how could i create a partition between my two rooms which have a huge frame in between them. The place was originally covered by curtains but putting up curtains on the ...
0
votes
2answers
219 views

Acceptable to install whole-house evaporative cooler with only a single supply vent?

My new house has a 20+ year old evaporative cooler on top of the roof. The cooler is ancient and rusted, difficult to service due to the location, and the forced air heating ductwork it feeds into is ...
0
votes
1answer
46 views

Is this pipe layout acceptable?

We recently had our heater and air conditioner replaced, and now the drainage pipe is installed on the floor of the basement. It's quite annoying and it wasn't like that before (it was on the walls ...