Pulling a vacuum....PROPERLY...

[I_bend_metal]

This is a little thread to show MY way of pulling a proper vacuum on a system and just how quickly it can be done.

This was an evap coil change out I did today. Lineset was disconnected in the basement for about an hour while I did sheet metal. The lineset was 30 feet long and I pumped this system down, so when the vacuum was pulled it was pulled on the lineset and evap coil only...

The total job took 2 1/2 hours.....here's the pics....

(sorry about some of the quality...my camera is not the best)



Pic. 1 - My pump set up....no manifolds needed...why would you want to pull a vacuum on them anyway??



Pic. 2 - The pump hooked to the unit....I use core removal tools to get the cores out of the way and also have a place ON THE UNIT to hook up my micron gauge. Why would you want to measure the vacuum anywhere else??

[IMG]http://i514.photobucket.com/albums/t...8124/Pump1.jpg[/IMG]

Pic.3 - Just before turning the pump on for the first pull....notice the time 2:09 pm and the gauge starts at 25,000 microns.

[IMG]http://i514.photobucket.com/albums/t...8124/Start.jpg[/IMG]

Pic 4. - 7 minutes and my gauge is at 200 microns.

[IMG]http://i514.photobucket.com/albums/t...24/200at10.jpg[/IMG]

Now I break this vacuum with about 2 psi of nitrogen and start the process all over again....

Pic. 5 - This is the second pull with the vacuum and I am now at 160 microns and have been at it for just 11 minutes...

[IMG]http://i514.photobucket.com/albums/t...24/1stPull.jpg[/IMG]

Pic 6 - Before the last pull, I break with nitorgen and put the cores back into the system with it under a possitive pressure so not to draw moisture into the system...I only need one hose to pull and my micron gauge at this point. Here is the set up....


[IMG]http://i514.photobucket.com/albums/t.../FinalPump.jpg[/IMG]

Pic. 7 - After ONLY 30 minutes I have pulled 3 vacuums on this system and after being off the pump now for 5 minutes.....here is my final reading....holding steady with no rise what so ever...

[IMG]http://i514.photobucket.com/albums/t...4/Finished.jpg[/IMG]

This thread is not to brag or to boast....I am not an engineer nor do I claim to be the best tech in the world...but proper procedures and proper tools will make all the difference in the world!!

[beachtech]

proper procedures and proper tools will make all the difference in the world!!

AMEN to that!!!

i still use two hoses on the last pull well i overkill everything anyways lol

[I_bend_metal]

AMEN to that!!!

i still use two hoses on the last pull well i overkill everything anyways lol

So if you are using 2 hoses on the final pull...where are you hooking the micron gauge?? I was doing the final pull with my core remover still hooked up but got paranoid about allowing in air and moisture while trying to put in that last core under a vacuum??

[beachtech]

lol it's a trane washed world around here, on the HP's i use the discharge port

i rarely pump a system down too.

worried about letting air in when disconnecting your micrin gauge, you put refer in while it is still atached to the system i sure don't

[y7turbo]

So if you are using 2 hoses on the final pull...where are you hooking the micron gauge?? I was doing the final pull with my core remover still hooked up but got paranoid about allowing in air and moisture while trying to put in that last core under a vacuum??

yeah your not supposed to put cores in under a vacuum.

Why even pull the cores on such a small system?

[HVAC/Stud]

Why can't you put the core back in while in a vacuum?

I do it on each vacuum, I use the field service valve tool.

STUD

[I_bend_metal]

Why can't you put the core back in while in a vacuum?

I do it on each vacuum, I use the field service valve tool.

STUD

Because under a vacuum you are going to allow outside air into the system...connect your micron gauge to the core remover and watch it when you put the core back in....it's just a little bit but your microns will rise dramatically...

[I_bend_metal]

yeah your not supposed to put cores in under a vacuum.

Why even pull the cores on such a small system?

Small?? That's an average size system for this area....I do resi only....and pulling cores makes things go that much faster....IMHO

[HVAC Tech]

Nicely Done

[Random Guy]

This is a little thread to show MY way of pulling a proper vacuum on a system and just how quickly it can be done.

This was an evap coil change out I did today. Lineset was disconnected in the basement for about an hour while I did sheet metal. The lineset was 30 feet long and I pumped this system down, so when the vacuum was pulled it was pulled on the lineset and evap coil only...

The total job took 2 1/2 hours.....here's the pics....

(sorry about some of the quality...my camera is not the best)



Pic. 1 - My pump set up....no manifolds needed...why would you want to pull a vacuum on them anyway??



Pic. 2 - The pump hooked to the unit....I use core removal tools to get the cores out of the way and also have a place ON THE UNIT to hook up my micron gauge. Why would you want to measure the vacuum anywhere else??



Pic.3 - Just before turning the pump on for the first pull....notice the time 2:09 pm and the gauge starts at 25,000 microns.



Pic 4. - 7 minutes and my gauge is at 200 microns.



Now I break this vacuum with about 2 psi of nitrogen and start the process all over again....

Pic. 5 - This is the second pull with the vacuum and I am now at 160 microns and have been at it for just 11 minutes...



Pic 6 - Before the last pull, I break with nitorgen and put the cores back into the system with it under a possitive pressure so not to draw moisture into the system...I only need one hose to pull and my micron gauge at this point. Here is the set up....




Pic. 7 - After ONLY 30 minutes I have pulled 3 vacuums on this system and after being off the pump now for 5 minutes.....here is my final reading....holding steady with no rise what so ever...



This thread is not to brag or to boast....I am not an engineer nor do I claim to be the best tech in the world...but proper procedures and proper tools will make all the difference in the world!!

Fixed the images.

[bustawrench1]

This is a little thread to show MY way of pulling a proper vacuum on a system and just how quickly it can be done.

!!

From what I learned in here recently, it's impossible to pull a proper vacuum unless you are an engineer.

[I_bend_metal]

From what I learned in here recently, it's impossible to pull a proper vacuum unless you are an engineer.

I don't think he has seen this thread yet....I linked the other one to this one...LOL

[tarheel_tech]

By the way,good set-up/procedure.But you are not doing it right regardless because your not an know-it-all engineer.