Air conditioner compressor

[pegger29]

Hi I have a 98 taurus wagon air conditioner compressor runs even when heater is on.... Any suggestions....

[Willyum]

Have you read through the owner's manual about this? There are provisions for the A/C to run as a dehumidifier when the heat is on.

[shorod]

I'm not sure about the A/C compressor running with heat, but certainly with defrost.

Also, if you have the Electronic Automatic Temperature Control (EATC) electronic climate controls, and use the automatic setting, the A/C compressor will stay engaged pretty much anytime the exterior ambient temperature is above freezing. To shut off the A/C compressor, you need to switch from the fully automatic mode to vent.

-Rod

[Ruzzinmd]

Check the wires going to the pressure switch/sensor located at the rear of the compressor. The insulation may be cracked and the wires shorted together.

[Huney1]

All it will do is use a little more gas, but not much because compressor doesn't have to work as hard when it's cool weather and doesn't take as much horse power to turn it. It's pulling humidity out of the inside air so low humidity actually makes heat feel warmer, same with a house AC. I have an 03 and tomorow I'll try it and see if the compressor is on when the heat is on and let you know. I agree with Rod, it's on in defrost mode to take the humidity off the windscreen.

[shorod]

Actually, humidity in heated air will make it feel warmer. Plus, when it's cold, if you have dry air, you will experience some nasty issues with static electricity. Here in Iowa, we use whole-house humidifiers on our furnaces in the winter to keep the humidity up so that we can turn the thermostats down a bit. The properly humidified air in the winter makes the house feel warmer. In the summer time, the A/C will keep the humidity down to make air feel cooler.

-Rod

[Huney1]

"Actually, humidity in heated air will make it feel warmer."
In my profession I went to a moisture control seminar and learned the importance of having a moisture barrier on the ground under the structure
to prevent the structure from absorbing moisture out of the ground. During WINTER a structure with high humidity inside feels colder than with low humidity. Summer inside with high humidity it feels warmer than low humidity.

http://www.madsci.org/posts/archives...2500.Es.r.html
"You're right in saying greater relative humidity makes a person feel warmer on a hot day...however, greater relative humidity does not necessarily make a person feel warmer on a cold day...and in fact usually does just the opposite. The reasons for this have to do with the body's response to environmental temperatures.

Even on cold days our bodies are perspiring. The sweat is evaporated into the layer of air next to our skins...cooling it's temperature and making us feel colder. Drier air allows this evaporation to happen quickly almost unnoticed by us. The addition of our sweat to the layer of air next to our skin is so small as to produce little noticeable cooling. In higher humidities, the moisture lingers, dampens our clothing...and the evaporational cooling is much more noticeable. Thus we feel colder rather than warmer."

We seldom see static electricity here 10 miles from the Ocean and high humidity prevails. Ambient temps 100F and 90% humidity make it absolutely miserable and can't even walk around outisde for ten minutes without being drenched. Heat prostration we call the, "BEAR," or, "Monkey on your back," and outside workers keep the fluids going and eveyone carries a bottle of Gator Aide so if they get nauseous indicating a loss of electrolites and/or fluids. One time I came within a hair of getting heat stroke and it took me the balance of the day to recover and the next day I felt BLAH and weak.

Winter time our humidity continues to stay high and when we get the wet months it goes high and it's cold so we run dehumidifiers so our houses feel warmer. My profession takes me in a lot of different homes and, winter or summer, the minute I walk in I can tell if the humidity is high and suggest the people get a dehumidifier and explain why.

A 1500 sqft frame wooden house with an enclosed crawl space three feet of the ground absorbs 50 gals of water a day then at night the moisture goes back in the ground, back & forth like that. I know, it sounds unbelievable, but that's what the experts tell us. So we go underneath and lay down a 10 mill mylar sheet, (same like they cover piles of lumber with), and the moisture collects on the mylar rather than being absorbed into the floor joists, sills and flooring and anything else under a house that will absorb mosture. The moisture transfers from the flooring into the walls and hence ends up making the interior more humid so it feels colder than it actually is. So you reach for the t'stat and kick it up a notch making your heating bill go up.

Anyway, that's the way it is in SC and I don't know about the Western US where humidity is low most of the time because I never lived there, but from what I know the laws of physics and thermo dynamics remain constant world wide.

Check out our local weather station, 91% humidity and 74 degrees at 7:AM.
http://weather.islc.net/hw3.php

[shorod]

Hmm, I'm going to have to think about this one a bit more. This is certainly out of my area of expertise. I just remember that every winter, I forget to turn the humidifier on late fall/early winter. We set the thermostat for what should be a comfortable temperature, and I'm still cold. That's when I remember, "Oh yeah, the humidifier is off." I turn it up to my arrow (marked for where the humidity was comfortable but not so high to condense on the windows) and all's well.

The link above seems to discuss extremes, very dry and rather humid. I'm guessing there is a happy medium humidity level that is in the "comfort zone."

-Rod

[Huney1]

"I'm guessing there is a happy medium humidity level that is in the "comfort zone." " Correct because if it's to dry your nose and throat dries out and it gets uncomfortable.

HA! Forgot to tell you about a downtown Bank and I don't know what in the world they did not grounding the building or if the rug is the electricity maker. Man, you walk across the rug to leave and reach for the metal handle on there door and it makes a blue arc that jumps out and pops you and I mean it really gives you a jolt. I remember reading static electricity is a jolt of 30,000 volts or something like that but no amperage and it's instantenous not sustained so it doesn't hurt anything but your pride. Like an old feller said about Ghosts, "They can't hurt you, but they can sho' make you hurt yo'self . . . . ."

[shorod]

Yeah, the static arcs won't physically hurt you, but they sure can wreak havoc on solid state electronics, especially FETs. The worst part is they weaken the junction, but don't necessarily cause it to open right away. A static failure may be noticed weeks or months later, which makes failure analysis tricky.

-Rod

[Huney1]

I built computers for a hobby and in our 'puter forum you hear about guys getting a dead mother board and they didn't use the wrist grounding strap and fryed a component or the processor. They make those straps you bolt under the car so it touches the ground when you stop and discharges static electricity and I've been meaning to get one for years but never did. Most of the time when we get a super cold front come thru it rids the air of humidity and then static electricity plays havoc with us flatland, swamp running, hill billies.

Almost completely flat land and every now and then you have a little hill that was once a big sand dune eons ago. You fly over the area and wonder where in the heck all the people live because all you see is salt water creeks, rivers, estuatries and the Great Santee Swamp with a zillion Cypress trees.