thanks a bunch Ron . best regards from Venezuela I am a retired worker from electrical statal company and my salary is about 5 bucks per month. so i decided to become HVAC technician to survive in this crazy economy and youtubers like you have been very helpful to me so god bless you.
Excellent presentation. For those more mathematically inclined the pressure drop/diameter relation for this parrticular case has a power of ca. 4.6. Double the diameter and you have increase the length 24 times (!).
Thank you this video is awesome. I’ve been trying to get someone to work on my 1940s Westinghouse refrigerator and not being able to find anyone I’m resorting to trying it myself.
High Ron, Great course info. I am looking for part 2 of the NATE math questions. Would you be able to post this information Thanks Greg Barrie Ontario Canada
Very well done, Ron. I've never heard or considered that the restriction blockage due to the filter dryer is usually within the first inch or less of the cap tubs entrance. Like to share info on drier. Sometimes the 'powder' is a result of the beads vibrating and wearing off very small dust, because of this I just accepted that the blockage could be anywhere in the cap tube, which it still could but your info on the opening portion was enlightening. I never use a beaded drier when I replace them but instead use the Sporlan cap tube driers, I've never had a reoccurring problem using a solid core.
I usually recommend replacing the entire cap tube when you replace the drier just to make sure. The blockage is "usually" in the first few inches, but not always.
If you work on gas orifices and have a wire gauge drill set I believe you can look up a conversion. And use the drill shank to measure your capillary size. I usually carry a 1 to60 gauge size drill set for soft brass only.
sir, can you say that how do i calculate the temperature and pressure drop in Capillary tube while designing it ? is there any equations or theories etc. ?
Hi Sir Ron Walker, i just watch your cap tube in 15minutes.. i am glad to see this lectures on videos, i work here in uae as a refrigeration technician and we usually do a customized refrigeration unit/system, i used J/B cap tube size chart for a new refrigeration system, but sometimes i might be get wrong by using the application because it gives me a bad result of cooling performance, we usually used a Tecumseh Condensing unit,is J/B cap tube chart is also applicable application for Tecumseh?
Sweet. So the resistance of the flow is proportional to the "area" of the circle represented by the inside diameter and the length. Cutting the length in half is the same as increasing the "area" of the inside circle by twice as much.
working on beverage air two drawer freezer with cap watched your vido there was a lot of service tech that work on it put it back together ran for three days in shop at -5 when put back in line cooks say won,t keep food frozen
hello sir i want to some suggestion i am going to rebuild d freezer which copper tube size i used in evaporator coil And lenth also .i wish reply soon thanx
I have a Senville Aura mini split and am a retired hvac tech. Problem in cooling both lines going to indoor unit are in low vacuum. Switching to heat they are both 500+ psig. I was told by Senville it was reversing vale and replaced, but have same results. I now think it has to be the capillary assembly with dryer in the outdoor unit. I am having no luck in finding a replacement complete assembly or a good place online for parts for mini-split units. I would think a metering device for any 18,000 btu mini-split would work. It has to be clogged. IMO.
I am working on a nite system apu on a on a semi truck I'm wondering if the capillary tube on the sensing bulb broke can I just re-solder it or do I need to change out the whole TXV valve and if so can I charge it my self
thanks Ron. how would you suggest soldering the cap tube into the evaporator ? I have seem the evaporator tube pinched to create a tight fit to one for the cap tube and then soldered in.how should it be done ?
I use wire terminal crimpers. Start with my large hydraulic crimper, then work my way down to manual crimpers as needed. The trick is to use something close to the same diameter as the capillary to retain a round opening that is large enough to insert the capillary tube into. I have a set of transfer punches that work well for that. Drill bit shanks would work too though.
So in these charts if the two kept tubes that you are using don’t have a number listed when you cross reference them am I to assume that there’s no changes needed in length
Hi Ron very informative video ,But one question no one has ever use a electronic lead solder to weld the tubes . Do not know why ,, but is it ok if i use it for my own DIY fridge repair ,,, Your advice please
Save yourself some trouble and use a stick of silver solder. I tried a roll of lead solder once when I didn’t have any silver. It lasted a little while, but eventually it began leaking.
Excellent video Ron. I am wanting to build a cloud chamber from a window air conditioner unit and need a cool plate of around -30C. Would it be too much to ask for a few hints through LinkedIn or something?
This is a very good explanation. I was wondering if it would be possible to have the same chart as you used in your video? If you can, could you send me the link? Thank you
hi, i was at a fridge tonight that was a cap tube system. it was low on charge refrigerant was 134a im just wondering how i would correctly charge the system if the charge is now known?? all i did was charge it to my suction pressure being a med temp application.
Hi happy new year.. i find some free on line programm on internet to resize tube.. i cant fint the original 1.88mm .1.3m so i put 2.00mm and the result is 1.73m length!! your video is very good but i am not so good to mathimatics ... its easy for you to check if is the Right size???? Thanks ... i am new on cooling system
+Ron Walker None hopefully. Temperature and pressure are related. If your temps are different then the pressures are different, indicating a restriction
Hello Ron, I ran into 5 units with the same problem. They all have capillary tubes, but the suction drops to 0 psig on start, discharge pressure were all about100 psig.during running. When unit is off, pressure equal at 100 psig. Thank you for any input.
That is a sign of moisture in the system, liquid ref. will expand in the strainer-filter causing ice and plug up the cap tube stopping the refrigerant flow, the strainer-filter will warm up and the cycle will repeat. evac. system and recharge.
The basic principle is explained by Bernoulli. The higher the velocity the lower the pressure. It has nothing to with length. It has something to do with velocity.
@1:50 This is inaccurate. The friction in the hose/tube slows the FLOW RATE, not lowers the pressure. The slower flow rate of the capillary tube means that inside the evaporative core of the system there is a shortage of refrigerant, resulting in a partial vacuum, which causes evaporation. In other words, the pump is pulling the freon out of the evaporator core faster than it can be replaced through the capilary tube. This results in a pressure drop *in the evap core* and then follows evaporation and the cooling effect.
I use to do 100s of cap tube systems a year, stores ice boxes. How to charge a cap tube system is pretty easy. Charge system until the suction line starts to frost, remove any liquid line connections as long as pressures are normal because you need to release a very small about of refrigerant at a time. Release refrigerant from suction line till the frost line starts to come back to the evaporator, done you are now using all the evaporator and not the suction line. Oh ya, I see a lot of guys using FILTERS on cap tubes NO the filter-can acts like an accumulator, I use strainers the ones that have a high side Schrader tap valve the small bullet looking filters.
Never worked on a Refrigerator before but decided to tackle changing the Compressor on my Kenmore Elite...Stopped Cooling. Welded in the New Compressor and Filter/Dryer...pretty proud of myself at this point! Vacuumed out the system and let it set for 24 hours... held a Vacuum... even prouder still!! Put some R134A Refrigerant in but the system refused to get even a little bit cold!!!! System would only come out of Negative to 10!?!? What did I do wrong?
Oh the hell with this all you need to do is get Horse power, type of application and type of gas to determine how long and wether you need a #1 #2 #3 or a #4 captube.
Bernoulli's principle (Pitot Tube) clearly explains how cap tubes reduce pressure. The relationship is between velocity and pressure. The faster the velocity the lower the pressure. This is best explained by a sprayer that sucks liquid since it create lower pressure due to high velocity created by the blowing of air. The same principle applies to why plane flies aided by its wings since lower pressure is created at the upper portion of the wing. The higher the velocity the lower the pressure until it reaches saturation point.
