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right so as you know im doing some playing with phase change atm but for my next project i would like to make a Refrigerant Recovery Unit so that i can reuse the gas and clean it in the process (it would also pass for a vac pump to lol)
i know the basic layout but where it all goes i dont know
you guys know a solution :up:
carl.
If your going to recover from a static unit, your going to need a compressor, oil separator, condenser, a good flare connecting filter, some access valves, and probably some hand valves or solenoids.
Diagram like this should work. The idea is your going to need to separate out the oil from the refrigerant.
http://www.thewiltedrose.net/adam/Ph...8/Recovery.JPG
got it back wards nol. Oil sep befor condencer and good idea to have an oil sep on suction side too.
With the size of the floated oil seps we got, I'd imagine with oil sep before you'd lose some refrigerant to the oil. This way you just have to have a good oil sep to separate refrigerant from oil right? Maybe your right.
Suction prob too, but at a bare minimum you don't necesarily need it. More need a bunch of access ports, hand valves, and filters so you can vac the recovery unit first to an acceptable micronity ;) Maybe put a micron gauge on the low side at the access even.
thats why you make a recovery unit for one refrigerant only when making them your self, they never get empty all ways leave some gas above atmosphere in the unit.
Need the oil sep BEFOR condensor for it to do any thing usefull, that is the fact of the matter.
Ah okay! Revise that then :) Mines the other way, maybe I'll flip it.
evocarlos- if your going to vacuum with it too try to use a powerful rotary, two is a lot better then 1 for vacuuming.
xeon- oil sep on suction side, brings the oil back to where? the system being evacuated or...? im real tired atm so please forgive but if you use a decent oil sep, why should you only use it with 1 refrigerant? if you use a rotary, but use a oil sep, will it be OK for evacuations of HFC's?
ive been wanting to build a similar thing evocarlos (but minus the vacuum pump :p: ) for reclamation but also for "cleaning" the refrigerant a bit (taking oil out). mainly because i have a couple blissfields, rechi's, and 2 cheapo floated oil seps :p:
much of this was covered if you use the search function.......The main consideration is if you are using a hermetic compressor(then the compressor oil must match the system oil being recovered) or a much better solution is buying a modern oiless compressor/recovery unit. Then it can be used on any rerigerant.(within technical specs.)
EDIT: Understood your question now. :PQuote:
Originally Posted by teyber
Are you going to put a solenoid or hand valve on that oil return?
An oil sep is never 100% effective.
On the suction side the oil is disposed of, it stops the oil from the unit being recovered from mixing and or flooding the recovery unit.Quote:
Originally Posted by teyber
I never seen a early recovery unit with a oil, separators. The hermetic compressors just used sight glasses and drains to remove the excess oil they recovered from a system.
in small systems ,especially cap tube ,the refrigerant is removed mostly in vapor form and little oil is removed from the original system.
Only when removing condensed (liquid)refrigerant like from receivers or holding tanks in larger systems is oil a real issue.
Righto eh? Sorry but oil foaming during rapid recovery kinda ensures oil gets taken up. Frankly the older designs sucked so I upgraded it! I've improved recovery time and quality with my design, all so helps prevent the machine from geting to warm during heavy use and not to mention less oil carry over :)Quote:
Originally Posted by wdrzal
Such a simplistic addition yet so much good things come from it, just becuase made that way doesn't mean it can't be made better! After 10 to 15 fridges/freezers I can fill a small bucket with all the oil the suction sep catches!
So for a new commer the suction sep will afford them lee way as they learn and not to mention further improves on an old design!
Perhaps in most application it is not "needed" How ever it does greatly improve the design making it far more solid and harder to kill a unit when some one with no experiance plays with it! So I will say it is some thing that should be put on any DIY unit!
well i was hoping that as the system im recovering was in a charged state i would not need to go mad with using the reclam unit as a vac but it would help lol if i can get my hands on a roto i will use but the normal hermectric comps is problly what i will get :)Quote:
Originally Posted by teyber
i can see the layout now but wher would all the valves go or shall i do a doodle and you can say yes or no :down::up:Quote:
Originally Posted by n00b 0f l337
is there no way to make the unit self priming like commercial units?Quote:
Originally Posted by Xeon th MG Pony
so that said if im recovering R134a and r404/r507 id be ok with POE oil in the recovery unit buying a unit is out of the qusetion to much cost and i would much preffer to make it as then i can say i made this lolQuote:
Originally Posted by wdrzal
on another note the main reasion for this thread i saw a unit on ebay but missed it i thought that makeing one cant be that hard here are some pics of the unit off ebay i missed
http://i90.photobucket.com/albums/k2...llR/6c30_1.jpghttp://i90.photobucket.com/albums/k2...llR/6f62_1.jpg
lol you've done this before nol havnt you :rofl:
http://img245.imageshack.us/img245/3...eryunitla2.jpg
Maybe something like this:
schräder valve > hand valve > maybe an accumulator here if you suck liquid out > compressor > condenser > filter > sight glas > hand valve > schräder
http://img124.imageshack.us/img124/8...eryunitdy1.jpg
With accumulator:
http://img182.imageshack.us/img182/4...mulatorfk6.jpg
thanks for the posts guys i will try and get hold of a compersser soon and do a build i will be doing lots of images so you can all see also i will be open to further sujestions when i start the build:up: watch this space
also i have some 134a in a bottle that has air mixed in is there any way to remove the air and will the reclam process sort that out?
Purify is a different process. You'd really need a phase separator then, remove the gaseous air from the liquid refrigerant a few times...
throw it in the freezer over night, take it out and put gauges on it. purge it to atmosphere very slowly till the pressure matches the pt chart, if don slowly and care fully you'll lose no refrigerant, only the air will be releasedQuote:
Originally Posted by EvoCarlos
(This is the approved method via Canadian ODP Laws of removing air from a tank)
hows that work then nol?Quote:
Originally Posted by n00b 0f l337
im not quite sure what you mean xeon so what will the frezzing process do to the 134a / o2 ?Quote:
Originally Posted by Xeon th MG Pony
"purge it to atmosphere very slowly till the pressure matches the pt chart" could you provide me with more info :)
freezing it just makes the refrigerant slower to boil off thus as you purge lends to les mixing, remember refrigerant is heavier then air, so all the air is sitting ontop of the R-134a gas. As we bleed off the air the R-134a will expand pushing the air off, as we do this our pressure tempriture relationship will again match saturated 134a.
ahh now i get it so the o2 sits on top of the gas :up:Quote:
Originally Posted by Xeon th MG Pony
so a wid guess is the pressure a set value?
or is it like 0 psig making -15 for r134a?
or other random figure
will the same work for all gas or just 134a
on and thanks for the help
First air is not O2 (oxygen) . Air contains about 20.9% oxygen(@ least @ my elevation around 1400' Above sea level.,78% nitrogen .o3% co2 and the rest is rare earth gases.Quote:
Originally Posted by EvoCarlos
You need to study and understand pressure/temperature charts for each refrigerant/ gas.
If you know the pressure,you know the temperature,if you know the temperature you know the pressure. This applies to tanks or system that have at least 1% liquid present(the number is actualy lower but 1% is very little liquid and a safe rule of thumb.If no liquid is present the p/t chart is invalid.
you also need to understand the critical pressures and temperatures and triple points of each gas. figures are not random.
air has a specific gravity of 1,some refrigeration vapors(or pure gases) are heavier than air or greater than 1 and some are lighter than air ,less than 1. You need to consult physical properties of each specific refrigerant or gas. most MSDS sheets list these but not all list complete info.
yes air is not o2 but you knew exzacllly what i ment i have been up 18hours lol:p:Quote:
Originally Posted by wdrzal
i did look in to the pt for 134a on here --> http://www.engineeringtoolbox.com/re...nts-d_902.html
and from what it tells me the boiling point of 134a is -15 @ 14.7psia which is 0psigg on the gages is it?< am i right do i get a cookie :rofl:
right will this do for an oilsep ?
http://i90.photobucket.com/albums/k2...chiller049.jpg
the red line shows where the pipe goes to
oh and ive got to fill it with scouring pad when i get some
hello peeps
well all i was waiting for was a compressor
i struck it lucky i asked a guy a work just out of the blue if he had a fridge he did not want and he said yes lol
he said the freezer works but the fridge did not so i went me for a look bonus the thing had 2 commpressors but the frige comp was rust'd up bad and had leaked from the hi side steel/copper joint so i went to work on it cut out the comp and got indoors just in time rain oh did it rain lol
http://i90.photobucket.com/albums/k2...chiller068.jpg
home made oil sep :) old argon bottle and copper scouring pads x5 and a strainer leftover from postals build
http://i90.photobucket.com/albums/k2...chiller063.jpg
it took ages to get the pads in :(
http://i90.photobucket.com/albums/k2...chiller065.jpg
bit of paint
http://i90.photobucket.com/albums/k2...chiller066.jpg
i found some MDF i had cut to put my amps on in the car but never used and made a base from it
http://i90.photobucket.com/albums/k2...chiller069.jpg
pipe work
http://i90.photobucket.com/albums/k2...chiller070.jpg
http://i90.photobucket.com/albums/k2...chiller071.jpg
http://i90.photobucket.com/albums/k2...chiller072.jpg
oil drain off i got a gas valve from B&Q for £5 had to dismantle it all to braze it all up
http://i90.photobucket.com/albums/k2...chiller074.jpg
http://i90.photobucket.com/albums/k2...chiller076.jpg
more paint and oil drain pipe to blow in to a cup of sorts
http://i90.photobucket.com/albums/k2...chiller077.jpg
its not finished yet but i'll up date as i go :)
hope you like what i done so far
carl..
nice... :)
you sure do live in a pretty area!
cheers mate yeah its a nice place miles away from every thing lol shame it was raining lolQuote:
Originally Posted by teyber
heres a bit more to the recovery unit b4 i go to bed its going to be good this one :)
i have put a suction line in and a 2nd suction line in (for somthing else later)but i drain'd the MO out and forgot to put the poe in so i had to suck it in with the 2nd sution line which was funny
http://i90.photobucket.com/albums/k2...chiller078.jpg
while it was running i put tape over the open pipes to stop the air getting in to that new oil but its shocking at what this compressor pulls on its own
http://i90.photobucket.com/albums/k2...chiller079.jpg
http://i90.photobucket.com/albums/k2...chiller080.jpg
Dude i gotta tell ya i love all these pics. That home made oil sep looks the business. Lets see how well it works. Have you chose which condenser you are going to use on it? How much cap tube do you need to put on it to ensure you are getting liquid into the recovery tank?
I wonder if this thing will suck the 2Kg of R134a out of my chiller lol.
No cap tube! just dump the condensor streight to the recovery tank.
as xeon said no cap its going to 1/4" straght in to the tank as the gas is liquid after the condencer so no need to use cap :yepp:Quote:
Originally Posted by Postal Dude
so i asume it will be low pressure then? bout 50-60 psig? <guesstamate
? durring recovery it will be a round 100 to 250psi depending on the gas, then it will settle to what ever the saturation pressure is at ambient temp.
it will always be above the pressure in the tank also... if not its not recovering :p:
edit-
carlos i really like the all flat black paint job......
got ya i never use a recovery unit b4 so i had to ask:)Quote:
Originally Posted by Xeon th MG Pony
well i was going to do bule(lowside) and red (hiside) but the paint was £6 a tin so i stuck with the black i had in stock £1 a can lolQuote:
Originally Posted by teyber
a bit more progress today but not much made another oil sep but need to get the bits for inside before i can mount it
i got some shut off valves from the local hardware shot and mooded them to fit
http://i90.photobucket.com/albums/k2...chiller084.jpg
more paint and a big empty space hrrrrm can you guess whats going there :up:
http://i90.photobucket.com/albums/k2...chiller085.jpg
ok so a bit of an update on the recovery unit
new purging device
http://i90.photobucket.com/albums/k2...chiller000.jpg
and 2nd oil sep and condencer fitted need to get some more fittings before i can make any more progress
the unit as of tonight
http://i90.photobucket.com/albums/k2...chiller001.jpg
Would now be a good time to get that fan up to you aswell? :D
Lookin great dude
yes :rolleyes: but that roto would be even nicer big fat SS out of it:DQuote:
Originally Posted by Postal Dude
also to report the unit works great i got a line tap off ebay cheap and well worth it http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=150252113438
i managed to get the gas out of the fridge and put it in a bottle the system is stuck with 6psig in the hi side i try'd every thing to get that last bit out bit its stuck
oh and it works :)