I am new to the site and only have abt three years in the industry. I had another tech tell me that you can diagnose alot just by temping (laser) the top of the hermetic compressor. He said all hermetics should run at between 110 to 135 degress F. He even uses that as a main factor to charge the unit. I had never heard of that before or read it. Can anyone expound on what he is talking abt? Thanks.
Twilly says your kidding right.
No Heat No Cool You need Action Fast
As long as those temps are what he said, and the suction line is beer can cold, you'll be fine.
Hopefully he is pulling your leg, and hopefully with 3 years experience you are pulling our legs.
you need a better source of info that that D/A
It`s better to be silent and thought the fool; than speak and remove all doubt.
Um, no.... Don't listen to another word that person says about HVAC equipment. On the bright side, what he says is a real jewel, ranks right up there with some of the other dandys I have heard over the years... How about this one:
The proper way to charge a system is to put an ampmeter on the compressor wiring and add refrigerant until the comprssor is pulling the amps that correspond to the data plate... Thats right, all that superheat and subcooling jargon the manufacturers are talking about is just to make us sound cutting edge... An ampprobe is all you need... Not even gauges.... Who knew...
Why buy an expensive laser thermometer when you can just feel the top of the compressor with your hand to determine if the charge is correct.
SH/SC? We don't need no stinkin' SH/SC.
I would advise you to ignore anything this "supertech" has to say about HVACR work. Oh, and buy a good HVACR text book and read it. With three years under your belt, you should have known this was a load of carp.
Here is one of my vodoo charging stories. I hired a tech and he was never able to charge a unit correctly. I finally asked him how he charged a unit. He told me he took the outside temp and the inside temp then subtracted the higher number from the lower number and added 40#. That is what the suction pressure should be.
I wore my hand out slapping my head. Then we went into intense training sessions. He ended up being a really good tech. As a matter of fact he called me today. He is back in the area and needs some tools I have for sale. Can't wait to see him again.
Signature on hold. Trying to find a real Jefferson quote I like. Others here have bogus Jefferson quotes too.
Rather than learning short cuts, learn the science behind the system.
Learn WHY superheat and subcooling are the correct metrics for charging.
Learn about how correct airflow affects these readings.
Learn to check airflow BEFORE even attempting to adjust or check the charge on a unit.
I'm sure there is more, but that will keep you out of trouble for a while.
Well how do you do it? Crack an egg on top and time how long it takes to cook?
Originally Posted by Twilly
3 rules for thermodynamics:
1. beer can cold suction line (not English beer)
2. 50# suction
3. When you have reached this stage, add 1 pound of refrigerant. (just to be safe)
Results guaranteed every time.
Beer Can Cold
when the mountains turn blue, your air conditioner is charged!
It matters not how strait the gate,
How charged with punishments the scroll,
I am the master of my fate:
I am the captain of my soul.
-- William Ernest Henley
I have found, via years of experience, that charging 2.34 pounds of refrigerant per Ton of system capacity at the start, is best. Then, add .76 pounds per cigarette smoked until proper TD is achieved.
The cigarette burning is directly correlated to the amount of refrigerant added.
Ohh... I have the manual that says that in my van. It's sitting right next to a hot bucket of steam.
Don't listen to that tech! Shortcuts are good for hacks. Do your job and do it well.
If you fix part of a system the whole system has your name on it.
I wouldn't trust a doctor who would give me a clean bill of health after only checking my forehead!
Treat the underlying problem, not just the symptoms.
"Quality is never an accident; it is always the result of intelligent effort. The bitterness of poor quality lingers long after the sweetness of low price is forgotten" --- John Ruskin
I needed a good laugh.
I nominate this thread for the Hall of Fame.
What lies behind us and what lies before us are small matters compared to what lies within us.
Two pressures, four temperatures = SUCCESS!
Boulder Heating Contractor
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