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VRF Commissioner

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#21 ·
ra88wfo said:
Absolutely! I am the Field Engineer for the LG Applied Rep in Wisconsin so I obviously see almost exclusively LG VRF.

It seems in the VRF world, us field employed have to be the blanket layer of knowledge to design, commission and service this equipment. I just want to get a central database that we can share our knowledge.
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So where do I get IOM and Service manuals for LMU187HV ?
 
#22 ·
Rider:
Two hole days to commission a Samsung vrf system. Wow that's neat.
Is the biggest problem the wire is installed upside down, sideways or backwards?
Do they use the wrong color wire? Is pink, purple and orange wire ok? Or is that wrong?
The Lon gateway that's neat! Do you commission the Lon device as well?
 
#23 ·
Two days is a starting point. I usually take what time is needed to make sure all is well. Wire must be 16/2 shielded communication wire with shielding conductors connected at all indoor equipment and grounded only at the outdoor unit.
Yes, we commission the Gateway, be it Lon or BacNet. We sell far more Lon devices then BacNet. We sell far more Gateways then touchscreen controllers.
 
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#24 ·
16/2 schielded wire ok neat. What would happen if you used 18/2 schielded? So the color doesn't matter right? I could use pink wire for the communications between multiple condensing units. And purple wire for the communications between the condensers and branch selectors. Then orange wire for the communications between the branch selectors and fan coils. Then how about yellow wire for the communications between the fan coils and thermostats. Is this how is works and my colors are ok? How about the color for the communications between the condensing unit to the Lon device? Would green be ok? Does the Lon gateway have a neuron I'd number? How does it serve up the points? Have you ever told anyone they have had the wrong wire or it was wired wrong. And the problem was really on your end. like a bad board in a fan coil or something?
 
#25 ·
We do Fujitsu Airstage. System design and pre-install checklists are put together at the distributor and given to the contractor. Biggest issue I've seen is dip/ rotary switch unit addressing. Control wiring is very simple, everything is daisy chained, provided with equipment.

While our TSA visits during the install process, commissioning (need for 10 year warranty, and done by Fujitsu) is done after system has run for 2 weeks.

Sent from my SM-G930V using Tapatalk
 
#26 ·
ace57745 said:
16/2 schielded wire ok neat. What would happen if you used 18/2 schielded? So the color doesn't matter right? I could use pink wire for the communications between multiple condensing units. And purple wire for the communications between the condensers and branch selectors. Then orange wire for the communications between the branch selectors and fan coils. Then how about yellow wire for the communications between the fan coils and thermostats. Is this how is works and my colors are ok? How about the color for the communications between the condensing unit to the Lon device? Would green be ok? Does the Lon gateway have a neuron I'd number? How does it serve up the points? Have you ever told anyone they have had the wrong wire or it was wired wrong. And the problem was really on your end. like a bad board in a fan coil or something?
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Usually the installers just buy a roll of white wire and then I mark it with a label maker. I also usually draw up a schematic of how it was wired and leave a copy on the job. I like home runs but daisy chain works. Any color will do, so long as it doesn't violate code. The install manual says 16/2 only. I can't promise the system will be trouble free if anything else is used. Usually problems come in the form of communication issues.
If the equipment isn't installed according to the manual, I walk until the installer fixes it. I handle warranty after startup and don't want the trouble of a misinstalled system breaking down all the time.
Gateway is addressed via IP, Subnet and mask addresses. Points are pulled conveniently, into the host system.
 
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#27 ·
Did I describe the wiring right? Can you help me with my terminology? So you have never told anyone that it was wired wrong and had them double check everything. Then turned out that the problem was a bad board somewhere? Where you live do you have to be a controls contractor to wire this system?
 
#28 ·
I live in Delaware. No, they are basic to install. Sometimes we aren't even the controls contractor on the project, so you just set up the gateway so the controls guy can pull the points when they're ready.
You can use different colors, there isn't any rules on wire color other then code (like red for fire).
You can usually tell pretty quick if it's a wiring or board issue.
 
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#31 ·
I am a certified comissioner for a few of the brands and work for a self performing company. We will do all of it with duct and line voltage being the exception. There are really no tricks to the comissioning, its all in the service troubleshooting later. There are lights and things going on inside these units that tech support have no clue what they are for but the guys troubleshooting them have figured out on their own. And then want you to share with them. SMH
 
#34 ·
Our company just wrote a full service contract on a building with 4 Daikin VRV3 systems installed by others. Had 2 failed compressors, leaking indoor coil on 1 system, refnet fittings in the wrong place etc. Corrected all but they didn't assign any air net addresses and I can't find the procedure to address the units. Can anyone advise me on this? Appreciate any help.
Regards Coolairman
 
#37 ·
I think my favorite 2 things I find on VRF systems I service is control wires entering the cabinet with the refrigerant lines, then zip tied to the leads for the inverter compressor, and ducted air handlers installed less than a foot above immovable structures...
 
#38 ·
eric1589 said:
Doubtful. These systems are a dream for manufacturers. They will be the only source of propietary parts on sprawling systems where every repair or change out demands you stick with them.
You need a new air handler on a 48 head system? I guess we know what manufacturer the new one is coming from. You need a new motor, heat exchanger, sensor, board, thermostat? Guess where your money is headed. These systems are long line, hooks for future sales. Hundreds of propietary parts replace a handful of potentially universal ones.

I havent worked on any but attended a few training classes from different manufacturers. They sound like a nightmare for places with shared space, especially if tenants are responsible for maintenance and repairs.
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And no matter how much a property owner comes to hate the particular brand they have, they are likely married to it forever, unless they are willing to also replace the piping system.
 
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