Questions about Air conditioning systems - other Heating and ventilation questions should use 'hvac'

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49
votes
6answers
190k views

Why does my A/C blow foul smelling air when it first turns on?

Most of the time when I first turn on the A/C in our 2008 Toyota Sienna, the air that blows out has a very distinct chemical - nasty smell. After a while it seems to go away. I'm not sure if I just ...
24
votes
1answer
2k views

A/C loses chill when turning on blower. Why?

Following the guidance from this Q&A, I measured the output temperature of my 2012 Town and Country A/C. Under the test conditions proscribed, with outside temperature of 87°F and 55% relative ...
21
votes
3answers
39k views

Is starting your car with the A/C on bad?

I was always yelled at by my father when I was first starting to drive when I left the A/C on when I turned off the car, and then later turned it back on, with the reasoning that I was ruining / ...
16
votes
4answers
4k views

Why is car A/C typically less reliable than fridges/freezers?

I just had the A/C in my car die on me again; air coming through the vents with the A/C is just as warm with it turned on as off. However, my fridge/freezer is something I've had for over 5 years and ...
16
votes
2answers
1k views

What are the dangers of refilling your air conditioner yourself?

Both of the Haynes manuals for my cars list refilling the refrigerant in your car as a do it yourself procedure. Both vehicles use R-134a refrigerant and the manual shows them being recharged with a ...
11
votes
5answers
19k views

Easiest way to disable the A/C compressor

My A/C system has a leak in it and my compressor is making an awful noise: probably needs replacing. Winter is coming though, and I really don't want to spend any time or money on tracking down leaks ...
11
votes
2answers
7k views

Why might I experience a power falloff after starting my car with the AC On?

I have a 2000 Chrysler Neon which generally runs well. I have noticed that if I start the vehicle, turn the AC on and reverse out of the driveway, the engine seems to struggle/sounds like it is going ...
11
votes
1answer
449 views

Does recirculated cabin air pass through the air filter?

In general, does air recirculated in the cabin (i.e. when the re-circulate button is engaged on the dash) pass again through the cabin air filter? I know that the cabin air filter filters outside air ...
10
votes
6answers
2k views

Can a car AC unit be run on just the car battery?

This might be a silly question but I was wondering if a car AC unit be run off entirely on battery or alternator? As this could help in Preventing power loss during important times such as ...
10
votes
8answers
101k views

How do you detect and deal with a refrigerant leak?

My heat works great, but my AC is nonexistent. Just blows out normal air, which in this weather is quite hot and unpleasant. I had the refrigerant refilled two years ago, but I haven't used the car ...
10
votes
2answers
301 views

Where can A/C condenser be located other than in front of radiator?

1953 F-100 w/ 428 Cobra Jet FE motor. I want to spare my grill and avoid putting the condenser in front of the radiator. Plus, it's already a beast to cool in hot weather, and I live in hell. (It's ...
10
votes
1answer
641 views

Volkswagen A/C Intermittent

I want to repair my Volkswagen Passat '07 A/C. I've taken it to two shops (dealer and independent) and they both say the entire a/c system needs to be replaced. The strange thing is, that sometimes it ...
9
votes
6answers
3k views

Using sunshine to cool down the car

Why can't the sunshine (that turns a car into an oven) be used to run the aircon? Or at the very least, a fan? For example - a long thin fan that fits into the top of the window - preventing it from ...
9
votes
2answers
18k views

Huge puddle of water under car

I parked my Dodge Viper after driving for about two hours (in July, ~90°F, AC at full blast). Half an hour later I noticed a huge puddle under the engine, on the passenger side. I am pretty sure it ...
9
votes
3answers
571 views

What can I do to prevent my air conditioner from smelling moldy as the temperatures begin to rise?

What can I do to prevent my air conditioner from smelling moldy as the temperatures begin to rise? Every year someone I know or myself begins to get an odor from their air conditioner that's musty or ...
9
votes
1answer
117 views

My feet turn black

I left the pedicure salon, started my car and drove less than 3 miles to pick up something from the store, when I stepped out of my car my feet were black... and I don't meant just from dirt, It ...
8
votes
3answers
81k views

Why am I smelling exhaust inside the cabin of my car?

When I drive my car the first few miles, I smell exhaust inside the car with the windows rolled up. It happens when I have either the AC or the heat/air on... What's going on?
8
votes
2answers
195 views

Shutting off fans at highway speeds

On my vehicle (92 Civic) and most others I've seen, the condenser fan comes on whenever the A/C clutch is engaged. This seems like a waste of electricity (and thus fuel) when cruising at 60-75 mph, ...
8
votes
3answers
8k views

What is involved to recharge the Air Conditioning System?

What is involved to recharge the Air Conditioning System? I believe you need a machine to do it, so I am guessing you can't do it yourself.
8
votes
1answer
249 views

What temperature should the A/C blow?

The A/C output temperature on my 2012 Chrysler Town & Country feels diminished, especially in the rear seats' A/C vents. So, I had the refrigerant drained, measured, and topped off (dealership did ...
8
votes
3answers
7k views

Air Conditioning Cools Intermittently

I have a 2001 Honda Civic. The A/C works pretty well - it comes on fast and blows cold. However, after 5 - 10 minutes it stops cooling and starts blowing warm air. If I turn the A/C off, after another ...
8
votes
1answer
146 views

Ford Econoline Van AC Failing

If the vents start putting out hot air when accelerating or driving up hills but are ice cold when idling, is that a sign of a failing blower pump or leak? I am dealing with a Ford Econoline E350. ...
8
votes
1answer
455 views

How to get items out of the HVAC system from a 2003-2007 Honda Accord

Before I ruin my dashboard/car, I wanted to know if my approach is correct. I don't know much about cars but logically, it seems like a simple enough task to remove vents, reach in and grab items, ...
7
votes
1answer
522 views

How do A/C professionals dispose of refrigerant?

The ubiquitous advisories and legislations against releasing A/C refrigerant into the atmosphere are well known - if you need to discharge R-134a or R-22 from your A/C system, have the gas evacuated ...
7
votes
2answers
67 views

Why does the Air Conditioner compressor cycle on and off even when it is hot in the car?

I have a 20 year old Subaru wagon, and the A/C seems to work fairly well except when it is extremely hot outside (> 100 F / 40 C - which happens a lot in the summer here). What I wonder about is that ...
7
votes
3answers
192 views

How do I fix my Heater & A/C in my car, suspect vacuum problem?

I didn't see this question asked after a search so I thought why not. I have a 97 GMC Sonoma with 90k miles that I barely drive. Since the hot summer is coming fast I went to use the AC and I am ...
7
votes
2answers
2k views

What problems can come from AC not running for years?

I have an 81 Chevy C10 that I inherited from my dad. This truck has mostly sat for the last seven years, with me running it enough to keep it in condition. I've been using this truck mainly for the ...
7
votes
2answers
3k views

AC: Fixing or Recharging?

I have Toyota Camry 2000. The problem is AC does not blow any cold air. So, I bought R134a and recharging it myself. It costs me about $12. However, it lasts for about a month. I checked with couple ...
7
votes
1answer
110 views

Measuring A/C refrigerant I got 96 PSI, is 96 PSI bad?

I bought a car refrigerant gauge online because my A/C is not cooling the air at all and the first suggestion was to check your refrigerant to see if it is empty or low. I found out where my car's "...
7
votes
1answer
68 views

Does R-134A refrigerant normally have oil (liquid at room temperature) in it?

Upon [legally] releasing some pressure from a car's (model year 2000) over-charged AC refrigerant loop that uses R-134A refrigerant, some of the released fluid surprisingly stayed liquid at room ...
7
votes
1answer
11k views

Low-side and high-side pressures lower than expected after AC repair

I just did my first automotive AC repair, after the compressor in my 2004 Lancer 2.0 ate itself, cracked its casing, and blew all the refrigerant out. I think I did the repair & recharge ...
7
votes
1answer
48 views

Longer crank time

Today I noticed something strange with my car. I was at a gym studio when I turned the key and I noticed it took a few "er er"'s longer before it started. As anxious I am about my expensive toys, I ...
7
votes
1answer
538 views

2014 Subaru Forrester AC Compressor clutch noise, slippage

We have a 2014 Subaru Forrester whose AC Compressor clutch operation is unlike other cars I've ever owned. The video linked is from when the car is cold and AC is engaged. It appears that the clutch ...
7
votes
1answer
2k views

Why would turning on the A/C affect my alternator output voltage?

So yet another chapter unfolds in the A/C gremlin saga of my LS1 Chevy. Backdrop A/C compressor is relatively new (2 years old) One of the belts is squeaking (not sure which one) Recently performed ...
7
votes
3answers
16k views

How to fix leaking air conditioning schrader valve

I have a 98 jeep cheerokee sport. The air conditioning coolant leaks. After doing some diagnostics, I detected audibly a hissing sound coming from the low input port, leading me to believe the ...
6
votes
3answers
14k views

How to recharge AC using booster from auto parts store?

The AC on my 2002 Chevy Cavalier stopped blowing cold in the fall and I had planned on getting it checked out and recharged once the AC check specials started. I saw this for $30 and it seems too ...
6
votes
2answers
2k views

Heat only works when engine is revving and at full power

On a 2004 Chrysler Sebring, the air only works when turned up to maximum power. At any of the 3 levels below that, no air comes out. Additionally, when the heat is on, it only blows hot air while the ...
6
votes
4answers
4k views

A/C does not cool when speeding more than 100kmph

I drive a 1.3 liter 2001 Mitsubishi Lancer. I have this weird problem with the a/c where it stops cooling when I try going above 100kmph. The a/c cools just fine under 100kmph. But when I go over ...
6
votes
2answers
257 views

Which knob setting best cooks the mold inside HVAC?

I am trying to eliminate odors inside HVAC by cooking the mold that is presumably causing them, as suggested in http://mechanics.stackexchange.com/a/146/15334 (which got 39 upvotes) However, I don't ...
6
votes
2answers
133 views

To Use Max AC or AC

If I understand properly, setting your vehicle in the AC setting will cycle air from the outside into your vehicle attempting to cool it before it is pulled in. Likewise, MAX AC only recycles the ...
6
votes
2answers
273 views

Does AC usage change based on blower speed?

As an example, my 2004 Honda CRV has air conditioning that is controlled by three controls: on/off button, blower speed knob, temperature knob. The blower speed knob affects the speed of the blower, ...
6
votes
2answers
90 views

When idling, AC does not work and engine overheats. What's the cause?

I drive a 2013 Chevy Sonic. Basically, the air conditioning does not blow cold air if the car is idling, only when in motion. It seems to blow the coldest during long periods of driving fast, such as ...
6
votes
1answer
179 views

Does a constant blown fuse always indicate a short?

My wife was driving our 96 Ford Windstar recently and she said right after she hit a bump in the road the ac stopped working and the instrument panel lights went out. I found the fuse from the wiring ...
6
votes
2answers
18k views

Engine Bogs down with A/C on highway

This started to happen relatively recent. It's 2003 Chevy Trailblazer. What is happening when the engine is idling and I turn the A/C on or the defroster (which also uses the A/C I believe), the ...
6
votes
1answer
247 views

Is it bad to mix different refrigerants?

I'm mainly wondering about different brands of refrigerants. In other words, mixing one brand of R134a with another brand, not mixing R12 and R134a (or anything like that).
6
votes
1answer
189 views

Does turning fan speed down affect AC compressor load

When I have my AC running, and I turn down the fan speed, does this also change the load the AC puts on the engine? Since the compressor puts load on the engine, and reduces fuel economy, I am ...
6
votes
2answers
51 views

1986 VW Westfalia van A/C

I had my AC refrigerant professionally changed to Red Tek in my van. It worked well for 2 or 3 years but then stopped cooling. I successfully refilled with difficulty and it was fine for a further ...
6
votes
2answers
2k views

Air Conditioning not cold on 2011 Honda civic

I have a 2011 Honda Civic LX with about 70k miles on it. As of a few weeks ago the AC really started having cooling problems; however, this all seemed to happen gradually. It seems to get a bit colder ...
6
votes
1answer
239 views

Do I have to get another Volvo?

I live in Florida and have mold allergies. Multiple times my 2008 Sienna van has a bad AC smell develop which makes me cough my head off. The dealer has cleaned the evaporator and ducts and the ...
6
votes
1answer
242 views

Why does my engine vibrate at idle only when I have the AC on?

2001 Honda Civic EX First noticed this problem when I got the car about a year ago. When the car is idling without the AC on, all is good. When I turn the AC and the clutch engages, it begins to ...