HVAC BTU and Ton
April 5, 2010 by Air Phase - All About Air Conditioning
Filed under hvac
I show how to calculate the tonnage raging based on the BTU information on a data label.
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@apnaconstruction You should put about 2 pounds of refrigerant per ton of air before starting the system for a weigh-in charge or for superheat and subcooling charge.
so how many lbs r22 i need to put in 3 ton unit
there is any calculator for that ??
how to calculated freon to put in unit ??
Dr z
thanks
@blissJesus1 You could get a ductulator from a HVAC parts house. Just line up your duct size and cfms to get your friction rate. Friction rate is the amount of drag there is on the air flow.
dr. Z,
I am trying to wrap my mind around friction rates, with length of duct by size; for example’ A duct is 40 ft. long, and is 6 in. by 9 in.. The quantity of air to be delivered is 400 cfm. What is the friction rate?. Is there a simple way to understand how to figure this out?, and thank you Dr. Z, your the best HVAC/ YOU TUBER.
@Aussie50 The refrigeration “ton” comes from ice. It takes 144 BTU to melt 1 lb of ice. A ton 2000lbs in the US would absorb 288,000 BTU in melting. The scale is based on it melting in a 24hr period which would be 288,000/24=12,000
So the ton of ice as it melts in one day’s time would absorb 12000 BTU per hour
@whyms1 Yep, Usually you can call the manufacturer and ask how much more refrigerant needs to be added per foot of line set.
@DrZarkloff Does the lenght of the line set effect the amount of gas needed to charge a HVAC system Mike Key West, Fl
@whyms1 the refrigerant charge should always be weighed in with packaged systems. Split systems, with the exception of mini split systems, should be charged by superheat or subcooling.
how do you calculate the amount of refreg gas to put in a system when rechargeing a hvac system
@yantur52 Thanks for watching.
You r the best teacher that I see at this time for real thanks to be here.
@uchemp I live in High Springs, Florida. I was born in Ohio, raised in Arizona and I’ve lived in Florida nearly all of my adult life.
Here are you from?
@DrZarkloff ill have to see how its done at a few of our customer’s buildings… and come back to you on that. there rough. even our experienced tech who can handle em, hates them to hell and back lol.
@death2opposeme All of the zoning controls that I work on are by computer. Alerton is the most common.
zone control systems just flat out dont work. they cant keep up in the summer time.
say Dr. Z you got anything on zone controls?? or 24v communication boards?? or anything like water towers, chillers, boilers, larger package units with rtrm or upc boards in them. ice machines or drink machines?? i do a little of everything. im lucky starting out on the large equip.
Hi dr zarloff just want to say you are doing a wonderful job in helping us young A/C techicians. im a A/C and refrigeration technician from Jamaica. a good topic would be types of compressor and how they work. respect, nuff luv seeen yeh man
I’m sure that it can be done. I all depends on the type of compressor. Be it scroll, reciprocating, centrifugal, screw, rotary, etc.
DR Z can you figure the btu.s by measureing current readings ? If so can you make a short video to prove the point thanks very much for your videos Pete from Newyork city electrician
1 ton = 12,000 BTU. BTU/HR: means British Thermal Units per hour. One BTU is the amount of energy that it take to raise one pound of water one degree F.
Just a question… I thought 1 ton = 12,000 BTU/hr. BTU is unit of energy, where BTU/hr is a unit of power? What am i doing wrong?
Thanks for watching.
thanks a lot man that really helps… i am a pretty ignorant person when it comes to things like this… i learned something thanks to you..
that’s right!!