Building My First SS Unit.

[fatguy1992]

Hi, i'v decided to build my own SS unit, not because i'm un-happy with my current unit, but because I got some AC units + will be getting tools cheap. I won't be starting most of the building until around November due to lack of time and money However I'v started painting the case and a few other things. Plus I have some questions.

Spec:

Compressor: 12000BTU
Condenser: That big one in the pictures below
Gas: R290/Propane
Evap/Linset: From Kayl
I'll also put some wheels on the bottom of the unit.

I'm only using R290 because its my first unit and I don't want to pay more money to get R507 in case I do something wrong and waste it, plus I'd have a hard time getting R507.

I'v done lots of reading and research into SS's lately, however I still have a few questions, they might be really dumb but I don't know.

1. Why is the capillary tube and other pipes wrapped around itself in a circle multiple times? (In the picture below).

2. Is that filter/direr in the below picture good enough or do I need another one? I think its too small, just want to check though.



Also I know the case needs a better clean out too. I don't have the pictures of it painted yet since its got to dark here now to take decent pictures. Trust me it looks way better




Thanks for any assistance.

[Postal Dude]

Hey mate.. some answers for you

1.) Cap tube is wrapped round like that for nothing other than to save space, look tidy, have it confined to one space and act as a vibration damper. You dont have to do this with your cap tube, normally the discharge line from the comp is coiled as a damper/De-super heater.

2.)In the pictures you have taken i cant actually see a filter/drier. Its normally placed directly after the condenser exit, if what i can see in the picture is in fact a filter/drier, then yeah you might wanna get a new one. Theyre cheap and definately worth it.

Final point to note. That condenser is MASSIVE!!! Way more than you will need for a single stage i think. EvoCarlos has one exactly the same as a first stage condenser in his triple stage cascade. It will work fine for sure, but its a bit overkill. It will require more gas to charge the unit more than it will aid performance IMO.

Regards

[fatguy1992]

Originally Posted by Postal Dude

Hey mate.. some answers for you

1.) Cap tube is wrapped round like that for nothing other than to save space, look tidy, have it confined to one space and act as a vibration damper. You dont have to do this with your cap tube, normally the discharge line from the comp is coiled as a damper/De-super heater.

2.)In the pictures you have taken i cant actually see a filter/drier. Its normally placed directly after the condenser exit, if what i can see in the picture is in fact a filter/drier, then yeah you might wanna get a new one. Theyre cheap and definately worth it.

Final point to note. That condenser is MASSIVE!!! Way more than you will need for a single stage i think. EvoCarlos has one exactly the same as a first stage condenser in his triple stage cascade. It will work fine for sure, but its a bit overkill. It will require more gas to charge the unit more than it will aid performance IMO.

Regards

Thank you, yes there is a filter/drier right next to the condenser exit and yes it is very small, so yeah i'll grab a new one.

Also I know that the condenser is massive, however the only reason i'm using it is because it came with the AC unit. Also I don't care if it needs more gas, cause R290 is cheap.

Thank you.

EDIT:

I'm also trying to decide if I want to make it a direct die or water chiller unit. As I need some sub zero cooling for my GPUs soon.

[fatguy1992]

Here is two pictures of the front part of my SS case, I ran out of paint so the other side isn't ready yet

[eligray]

Postal dude, I believe that people generally wrap cap tube b/c of the subcooling.

However, I believe that it also increases the suction pressures... but I believe that it is generally considered to be worth it.

Would you guys agree with my theory that the cap tube is best to wrap (for subcooling purposes) towards the end of the suction line that is near the compressor, since it means that the majority of the volume of the suction line is still at the lowest temp possible, therefore keeping suction pressures relatively low? Basically I'm thinking that it will get you as much subcooling as a standard wrap, but not raise suction pressures as much since only a small amount of the gas is actually warmed (near the compressor), instead of warming the entire suction line.

[[XC] gomeler]

I'd prefer to wrap the entire suction line at the cost of warming it up slightly. The wrapped capillary stiffens the line and makes people a little more careful so maybe it helps prevent noobs from snapping the lines? Regardless of where you wrap the suction line you are going to be dumping a minor amount of heat into the return gas, might as well spread it out and make the most of it.

[Foamy]

Wow you are going to make one of the biggest single stages i ever saw

[kayl]

Most of the stuff can be cut away as its not needed in our systems.
Have you changed any of the piping yet, just from one of the pics it does look quiet right

With these system we use much smaller and longer capillary tube.
You wrap the capillary line around the cold suction line to help cool the refrigerant and remove heat before it goes to the evap head.

you also normally have a coil before the condenser to reduce strain on copper joins from the compressor vibrates when running.


With that air condition you need to figure out which is the condenser and what is the evaporator. If it’s a reverse cycle air-conditioned there is some tubing and electronics that arnt used. My suggestion would be to cut almost all of the wiring out and start again.
You will find that the fan on the condenser blows more air than needed, and might want to use the thermostat to turn the fan on when the condenser gets too hot, and switch off again when condenser at a good temp. Idelly you would be better using a smaller condenser and a 120mm fan, reduce the charge of flammable gas and also improve your temps at the same time.

Heres a propane pressure charge so you know what temps you get at what pressures.

[Foamy]

Originally Posted by kayl

Most of the stuff can be cut away as its not needed in our systems.
Have you changed any of the piping yet, just from one of the pics it does look quiet right

With these system we use much smaller and longer capillary tube.
You wrap the capillary line around the cold suction line to help cool the refrigerant and remove heat before it goes to the evap head.

you also normally have a coil before the condenser to reduce strain on copper joins from the compressor vibrates when running.


With that air condition you need to figure out which is the condenser and what is the evaporator. If it’s a reverse cycle air-conditioned there is some tubing and electronics that arnt used. My suggestion would be to cut almost all of the wiring out and start again.
You will find that the fan on the condenser blows more air than needed, and might want to use the thermostat to turn the fan on when the condenser gets too hot, and switch off again when condenser at a good temp. Idelly you would be better using a smaller condenser and a 120mm fan, reduce the charge of flammable gas and also improve your temps at the same time.

Heres a propane pressure charge so you know what temps you get at what pressures.

You got other charts as well? From other gasses that is..

[kayl]

Originally Posted by Foamy

You got other charts as well? From other gasses that is..

for other gases you should be able to find them on the web ie r404, 507
r290 you wont

[fatguy1992]

Originally Posted by kayl

Most of the stuff can be cut away as its not needed in our systems.
Have you changed any of the piping yet, just from one of the pics it does look quiet right

With these system we use much smaller and longer capillary tube.
You wrap the capillary line around the cold suction line to help cool the refrigerant and remove heat before it goes to the evap head.

you also normally have a coil before the condenser to reduce strain on copper joins from the compressor vibrates when running.


With that air condition you need to figure out which is the condenser and what is the evaporator. If it’s a reverse cycle air-conditioned there is some tubing and electronics that arnt used. My suggestion would be to cut almost all of the wiring out and start again.
You will find that the fan on the condenser blows more air than needed, and might want to use the thermostat to turn the fan on when the condenser gets too hot, and switch off again when condenser at a good temp. Idelly you would be better using a smaller condenser and a 120mm fan, reduce the charge of flammable gas and also improve your temps at the same time.

Heres a propane pressure charge so you know what temps you get at what pressures.

Thank you for the info and the chart

I haven't change any of the piping yet as I don't have the money to get the tools

This AC unit wasn't reverse cycle, its only cooling and I know that the condenser that I took a picture of is not the evaporator. I have the wall mounted evaporator unit out in the garage. The only reason i'll use that condenser is because it came with the unit

Thanks

Originally Posted by Foamy

Wow you are going to make one of the biggest single stages i ever saw

Thanks, well its cheaper then buying new parts, and AC unit always seem to make big SS's

[Postal Dude]

Wrapping the cap tube round the suction line is for sub-cooling i know. Sorry if my answer was confusing. In the picture posted the cap tube is coiled up by the manufacturer. I thought he was referring to this.