Lg lmu540hv

frozenone · 12-02-14, 03:29 AM

Do you pull vacuum from Gas or Liquid service port on the LMU540hv

jeff5may · 12-02-14, 04:44 PM

In what condition is your system? Brand new, full of charge? Upgrading to a different indoor configuration? Used, just fixed a leak? It really makes a difference.

frozenone · 12-02-14, 06:37 PM

Brand new system I just need to vac it then release refrigerant. Here's the picture which is the service port.

jeff5may · 12-02-14, 07:08 PM

the pic has the service ports facing down. If the system is brand new, you can pull vacuum from either line. If you connect both, you can pull them both at once. Might save some time. In the factory position, both service ports are connected to the lineset side of the valve.

Don't forget to pressure test your indoor unit and lineset before you do a final vacuum. This will test all your connections under high pressure conditions, revealing any looseness that a vacuum test alone might not find.

When pulling a deep vacuum, make sure and have caps tightly connected on everything your gauges aren't connected to. The seals and service valves might not leak at all, but having caps on removes all doubt.

Good luck!

frozenone · 12-03-14, 01:49 AM

thanks for your help jeff! due to the outdoor unit requires a branch distribution box to connect to indoor unit, how do i pressure test each indoor unit separately?

jeff5may · 12-03-14, 10:49 AM

Start out by solidly anchoring your distro box to something strong. Begin by connecting your lineset to the distro box, leaving all caps on the branch connections on the box. Make sure the caps are all tight and won't leak. Pressurize and check lineset for leaks. Repair leaks as needed. Relieve pressure, connect one indoor unit branch to the distro box, leaving extra caps on the box. Pressurize and check first branch for leaks. Relieve pressure, repair as needed, connect second indoor unit. Repeat for remaining indoor units.

Once all the indoor units are connected, let the whole system sit under pressure for an hour or two. Within the first couple of minutes of pressurizing, the circuit will equalize to a certain pressure. Unless the environment changes, the pressure will remain constant if you don't have any leaks. If the pressure drops more than a few PSI, start hunting for leaks with the soapy water. If not, you are ready to pull vacuum.

At this point, I cannot stress enough the need for adequate tools and instruments. Since you are doing the job on your own, you MUST acquire a decent vacuum pump and micron gauge. Also, assembling a collection of specialty tools (tubing benders, gas torch, flare wrenches, pipe cutters, wire cutters, multimeter, etc.) before you start the install will quickly pay themselves back in finish quality and time not spent. All this has been covered in previous threads in the forum.

When in doubt, buy the ridgid or bosch or milwaukee tool over the lenox or harbor freight tool. If you decide not to keep your collection, the lifetime tool will fetch a much higher resale price than the disposable clone. It also helps keep the American industrial machine on its feet.

Since you are running an R410a system, pulling multiple deep vacuums is vital for the longevity of the outdoor unit. Before you let the charge out of your outdoor unit, be certain your installed system is able to hold a deep vacuum and is not contaminated with anything.

frozenone · 12-04-14, 03:47 AM

Thanks for all the info. For the indoor unit wiring , I just have to match it with outdoor right?

hotwirez · 12-04-14, 08:57 AM

Quote:

Originally Posted by frozenone

Thanks for all the info. For the indoor unit wiring , I just have to match it with outdoor right?

FYI, with stranded wire you should use crimp on fork lug connectors.

John

12-02-14, 03:29 AM	#1
frozenone Lurking Renovator Join Date: Dec 2014 Location: california Posts: 6 Thanks: 1 Thanked 0 Times in 0 Posts	Lg lmu540hv Do you pull vacuum from Gas or Liquid service port on the LMU540hv

12-02-14, 06:37 PM	#3
frozenone Lurking Renovator Join Date: Dec 2014 Location: california Posts: 6 Thanks: 1 Thanked 0 Times in 0 Posts	Brand new system I just need to vac it then release refrigerant. Here's the picture which is the service port. Attached Thumbnails Last edited by Daox; 12-04-14 at 08:19 AM..

12-03-14, 01:49 AM	#5
frozenone Lurking Renovator Join Date: Dec 2014 Location: california Posts: 6 Thanks: 1 Thanked 0 Times in 0 Posts	thanks for your help jeff! due to the outdoor unit requires a branch distribution box to connect to indoor unit, how do i pressure test each indoor unit separately? Attached Thumbnails Last edited by Daox; 12-04-14 at 08:19 AM..

12-03-14, 10:49 AM	#6
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,428 Thanks: 431 Thanked 619 Times in 517 Posts	Distribution box install Start out by solidly anchoring your distro box to something strong. Begin by connecting your lineset to the distro box, leaving all caps on the branch connections on the box. Make sure the caps are all tight and won't leak. Pressurize and check lineset for leaks. Repair leaks as needed. Relieve pressure, connect one indoor unit branch to the distro box, leaving extra caps on the box. Pressurize and check first branch for leaks. Relieve pressure, repair as needed, connect second indoor unit. Repeat for remaining indoor units. Once all the indoor units are connected, let the whole system sit under pressure for an hour or two. Within the first couple of minutes of pressurizing, the circuit will equalize to a certain pressure. Unless the environment changes, the pressure will remain constant if you don't have any leaks. If the pressure drops more than a few PSI, start hunting for leaks with the soapy water. If not, you are ready to pull vacuum. At this point, I cannot stress enough the need for adequate tools and instruments. Since you are doing the job on your own, you MUST acquire a decent vacuum pump and micron gauge. Also, assembling a collection of specialty tools (tubing benders, gas torch, flare wrenches, pipe cutters, wire cutters, multimeter, etc.) before you start the install will quickly pay themselves back in finish quality and time not spent. All this has been covered in previous threads in the forum. When in doubt, buy the ridgid or bosch or milwaukee tool over the lenox or harbor freight tool. If you decide not to keep your collection, the lifetime tool will fetch a much higher resale price than the disposable clone. It also helps keep the American industrial machine on its feet. Since you are running an R410a system, pulling multiple deep vacuums is vital for the longevity of the outdoor unit. Before you let the charge out of your outdoor unit, be certain your installed system is able to hold a deep vacuum and is not contaminated with anything. Last edited by jeff5may; 12-03-14 at 10:51 AM..

12-04-14, 03:47 AM	#7
frozenone Lurking Renovator Join Date: Dec 2014 Location: california Posts: 6 Thanks: 1 Thanked 0 Times in 0 Posts	Thanks for all the info. For the indoor unit wiring , I just have to match it with outdoor right? Attached Thumbnails Last edited by Daox; 12-04-14 at 08:19 AM..

12-02-14, 04:44 PM	#2
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,428 Thanks: 431 Thanked 619 Times in 517 Posts	In what condition is your system? Brand new, full of charge? Upgrading to a different indoor configuration? Used, just fixed a leak? It really makes a difference.

12-02-14, 07:08 PM	#4
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,428 Thanks: 431 Thanked 619 Times in 517 Posts	the pic has the service ports facing down. If the system is brand new, you can pull vacuum from either line. If you connect both, you can pull them both at once. Might save some time. In the factory position, both service ports are connected to the lineset side of the valve. Don't forget to pressure test your indoor unit and lineset before you do a final vacuum. This will test all your connections under high pressure conditions, revealing any looseness that a vacuum test alone might not find. When pulling a deep vacuum, make sure and have caps tightly connected on everything your gauges aren't connected to. The seals and service valves might not leak at all, but having caps on removes all doubt. Good luck!