Oil sep and Expansion tank

[boardy]

Seems like an odd question but I've been wondering for a while.

I have seen and heard of people making their own Oil seps and Expansion tanks. I have 2 simple questions for the people that know -

1) How do I make an oil sep?
2) How do I make an expansion tank?

These are pretty much the only 2 things stopping me from building the first stage of my cascade. I have some condensors coming from Drewmeister, 25uF run caps for my rotaries from jeebay and a CPEV for the 1st stage which should be here soon.

The HX, oil sep, and expansion tank I want to make as they cost buckets to buy here in UK :(

Cheers for any help guys
Boardy

[n00b 0f l337]

HX get soem tube.
Oil sep, use a spare MAPP Bottle. Expansion tank, just some 1" tube.

[hatemi]

Oilsep: http://teampuss.com/forums/viewtopic.php?t=225

Expansion tank: Its just an empty tank that you connect with short piece of captube to the suctionside of your second stage. Refrigerant recievers are one easily aceesable part that you can use as an expansion tank.

[n00b 0f l337]

Hatemi why captube? Wouldnt that really increase the balance time? I'd use 1/4" or bigger. Also it can be on a high stage I beleive if you really want to lower pressures.

[runmc]

Oilsep: http://teampuss.com/forums/viewtopic.php?t=225

Expansion tank: Its just an empty tank that you connect with short piece of captube to the suctionside of your second stage. Refrigerant recievers are one easily aceesable part that you can use as an expansion tank.

captube :woot:

[gclg2000]

:2cents:

Expansion tanks aren't needed. It should help pull down times though i suppose.

[runmc]

:2cents:

Expansion tanks aren't needed. It should help pull down times though i suppose.

I agree - they aren't needed unless you want to use one.:2cents:

[kayl]

:2cents:

Expansion tanks aren't needed. It should help pull down times though i suppose.


some systems do some dont. really depend on how much 1150 or second stage refrigerant you put in there and what ya happy with at static charge.


anything over 250psig static is scary personally.
heres how i did my oil sep
http://www.xtremesystems.org/forums/showthread.php?t=72584&page=4&pp=25


you want the gas to enter closer to the bottom of the oil separator. flow through copper scrubs and the out at the top of the oil sep.
oil return is at the bottom of the oil sep, need a hand tap and few feet of capillary line back to the suction line close to the compressor.
open it say once an hour.

with the expansion tank once the gas has been sucked from the chamber its at a low pressure and wont effect the system what so ever, its basically none existent.
When the system shuts down the gas slowly bleeds back into the expansion chamber and system pressure equalizes. On start up the gas slowly comes out reducing the high side pressure on pull down and wont hit the first stage as hard keeping the hx temps cold still.
a length of 2" copper pipe should be ok for a 2 stage cascade.
In my current cascade I don’t have a expansion chamber but it would hurt to have one in there.
i found the shorter the capillary line the more high stage refrigerant you can have in the system. Sometimes when ya got a lot of gas in the second stage if first stage isn’t rock solid the hx cant handle pull down.

[boardy]

Cheers for the replies guys.

HX I'm going to use 1/2" outer and 1/4" inner leading out to 2 1/4" outlets. Sound good?

That link was really helpfull and I think I'll get onto that this week if I can get hold of some wool. Which is best, copper or steel? I read that copper is best but just wondering what your opinions are.

As for the expansion tank, I just wanted to get the unit as safe as possible really. It's gonna have R23 as 2nd stage gas so will be pretty high pressure. Just don't want the thing having stupidly high static pressure. I'm not fussed about pull down times, I just want the thing as safe as possible.

What is the best thing to make the expansion tank out of? An old empty Mapp bottle with the valve cut off and a plate braised onto the bottom, or leave the valve there and drill a hole for some 1/4" going to cap?

Cheers for the help guys, appreciate it :)
Boardy

[Xeon th MG Pony]

I'm desining a Oil scrub bassed of the comercile helical units using Brass mesh and plate to form the helix. Untill I have the money to build it and test it I'm not going to say much more, and if it works Good I'll give ya all the details

[boardy]

Sounds interesting mate. Lemme know if it works ;)

Boardy