Is Measuring Superheat at Compressor of Any Value?

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The suction line sweats heavily at the compressor and the liquid line leaving the compressor is barely warm. This suggests to me the system is overcharged. It's easy for me to measure the superheat at the compressor (split unit), but not at the evaporator. Will a reading at the compressor tell me anything useful about the system charge?
Another way of asking this is how much is a typical difference in the evaporator superheat and the condenser superheat in a split unit? The suction line is about 30 feet long.
-- Ken
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It tells me that *if* you are a tech, then you need to go back to school.

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Anyone have a helpful answer?
wrote:

-- Ken
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Ken Hall posted for all of us... I don't top post - see either inline or at bottom.

--
Tekkie

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On Mon, 24 Jul 2006 18:57:41 -0500, Ken Hall

Yup. Step AWAY from the machine. You dont have a clue what you're doing and all you can do is make it worse. Seek out the help from someone professional in the business. Bubba

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Not a lot of difference in a 30 foot lineset, if the suction line is well insulated.
How many tons? Which refrigerant? Orifice, or TXV coil? Liquid line temp and pressure at condensing unit? Suction line temp and pressure? Good air flow through evaporator? Good air flow through conensor? Ourdoor temp? Temp of hot air top of condensor fan? Return air temp indoors? High humidity indoors? Supply air temp indoors?
--

Christopher A. Young
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I had an orifice, but my company moved me into a cubicle with a 28 degree superheat. only air flow is from the next cubicle after he has a bean burrito lunch.This does cause some thermal expansion from the warm breeze. sometimes the expansion lets too much liquid out and he has to run to the toilet.
ourdoor? nice day today, it was.
my condensor is 0.47 Mfd.
snicker

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The Sex Life of an Electron
---------------------------------------------------------------------- ----------
One night when his charge was pretty high, Micro Henry decided to try to get a cute little coil to let him discharge. He picked up Millie Amp and took her for a ride on his Mega cycle. They rode across the Wheatstone bridge, around by the sine wave, and stopped in a magnetic field by a flowing current. Micro Henry, attracted by Millie's characteristic curves, soon had her resistance at a minimum and his field was fully excited. He laid her on the ground potential, raised her frequency, lowered her capacitance and pulled out his high voltage probe. He inserted his probe into her test socket, connected them in paralell, and began to short circuit her shunt.
Fully excited Millie Amp exclaimed, "Mho, mho, mho." With his tube operating at it's maximum peak current and her coil vibrating from the current flow, she soon reached her maximum peak potential. The excess current flow had gotten her coil hot and Micro Henry started rapidly discharging and soon had drained off every last electron.
They fluxed all night trying various connections and sockets, until Micro Henry's bar magnet had lost all of it's field strength. Afterwards, Millie Amp tried self induction and damaged her solenoid. With his batteries fully discharged, Micro Henry was unable to further excite his generator, so they ended it all by reversing polarity and blowing each other's fuses.
--

Christopher A. Young
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I had much the same problem. We had an Arab kid move into a Jewish neighborhood, and a Jew into an arab neighborhood. Called it a heat exchanger. Or maybe it was a hebe exganger? Kant thpeek too goot.
His Mom forgot to put the dryer sheet in. The static was so good, her son couldn't stand up from the carpet where he was sitting in front of the TV. Doctor called it "underwearcharged". However, his brother Amir got up no problem, until he got his suspenders caught on the electric socket, and fried himself. The doctor said, Oshkosh, and b'gosh, first case he'd seen in someone so younger -- overallcharged.
Nearly got ticked at a weigh station for being over capacity in my Farad Pinto. Had a condenser in my farad. I managed to make enough money on that job to save the family joules, tripped off a couple burglars with a circuit breaker. Whacked them upside the head, and they tripped off. Then I banged em on the floor, the judge threw out the case, said it was a ground fault breaker.
Couldn't overcharge the customer, had to get what the job was worth. Though, he did tell me to jamb the bill some where. That was impolite, and I told him so. Those rich folks living in nice big expansions.
Well, he told me to truck off. So, I decided to hit the gas (R-22 that is) and blow the joint. I knew the system was working when the suction line was beer can cold, and the donkey started to shiver out in the barn. Really keeping his ass cold.
Knew his kids were cold, too. They were in the playroom watching Sesame Street on the TXV. Shivering, and wearing coats of paint.
--

Christopher A. Young
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Maybe I was drunk when I wrote my nonsense. What's your excuse? your not supposed to hit the cactus squeezings.
Are you allowed to smoke whacky weed? that must be it.
"Kick me", the sign says.What did I start? so much regret.

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It's been a challenging week. Hot, 91F and humid today. My share of things gone right, and plenty that gone wrong. Time to loosen up a bit, and be silly for a few minutes. Mormons don't need old wine to be silly.
Your epidermis is showing.
--

Christopher A. Young
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When I bend over I have a little plumber's crack cleavage, yes. Nice of you to notice.
you just have as much fun as you please. just surprised me to see you ramble on for so long. New wine is cheaper. here is a place in NY where you can donate yours if you don't drink it: http://www.halfbakery.com/idea/Liquor_20for_20the_20Homeless
iggy from ziggy needs no wiggy no blue pills needed for piggy

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Well, after 15 years in the church, there isn't much wine left around the house.
But, it's been another really hot day. And so you can expect a little more silly.
--

Christopher A. Young
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On Wed, 26 Jul 2006 02:37:35 GMT, "Stormin Mormon"

No, just grapes of wrath.
Except the Osmonds. I like the Osmonds.
--
-john
wide-open at throttle dot info
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Never met any of the Osmonds. But when I was a kid, some of the girls at my school had a major crush on Donny. I never could figure out what they saw in him. Just another fellow, I thought.
--

Christopher A. Young
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On Tue, 25 Jul 2006 02:13:24 GMT, "Stormin Mormon"

Thanks for your reply.

3.5
R22
capillary tubes/orifice

Temp of line out of compressor (between compressor and condenser) 102F Can't measure pressure because fitting is damaged/deformed

Temp is about 45F Pressure 61

Yes
Yes
79F
91F
55F
45%
73F
-- Ken
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3.5
R22 CY: Sounds like a typical residential system.

capillary tubes/orifice

Temp of line out of compressor (between compressor and condenser) 102F Can't measure pressure because fitting is damaged/deformed CY: 102 isn't that bad. I'd neglected to ask / mention. The liquid line oughta be close to the outdoor air temp. If it's much hotter than the outdoor air, it indicates dirty condensor.

Temp is about 45F Pressure 61 CY: Hmm. About ten degrees superheat. Should be more like 15 degrees. That suggests the overcharge you were wondering about.

Yes
Yes
79F
91F
55F CY: Wow, your house is 55F?

45%
73F CY: And the furnace is on? Pumping hot air into the house?
-- Ken
CY: Well, seeing as how it's making 18F difference in indoor air, something is right. But the sweat back does indicate overcharge.
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On Tue, 25 Jul 2006 21:10:37 GMT, "Stormin Mormon"

Yes, I got supply and return reversed in my head,
Thank you for your help.
-- Ken
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At the condensing unit is where I typically measure superheat. Tuck my temp probe into the end of the black foam wrap.
Also check the amperage draw of the condensing unit. But, for the moment it sure sounds like overcharge and flooding evaporator. Do you have good air flow through the evaporator? And what kind of temps and pressures are you showing?
--

Christopher A. Young
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In order to effectively troubleshoot your system over the internet we will need from you the following:
air inlet & outlet temps at the evap suction line pressure suction line temp near the evap suction line temp near the compressor
air inlet & outlet temps at the condenser liquid line pressure liquid line temp near the condenser outlet liquid line temp near the metering device
make & model number of equipment and type of refrigerant.
suggest you learn a tad bit more before you start diagnosing things you know jack-shit about.
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