VRF System Overview

[@tokenlectronix5223]

Sounds like a engineer's wet dream and a technicians worst nightmare.

[@Fernando-bq3cv]

bruh i kid u not im barely a month in to commercial hvac with almost no experience and i had a service call for this exact vrf i was so overwhelmed lmfao

[@Justaguy0420]

I work with LG and Mitsubishi VrF HR and the “Free energy” or moving BTUs from one area to the next doesn’t actually work in the field. I had service call after service call from a vertical system design in a 650 apartment unit mid rise building. When we had a diversified system neither heating or cooling were doing any actual work. I personally logged hundreds of hours of data showing the delta across each IDU proving no change of state. This became such a problem we flew LG engineers out from Korea and in short they acknowledged a design flaw with the BC box in heat recovery. This issue became a lawsuit and insurance claim as we were the installing mechanical contractor. LGMV Multiv4 was the equipment installed. I have similar stories with Mitsubishi equipment although Mitsubishi design is by far better than LG. Water hammer noise with the BC box shutting down its solenoid was also a huge complaint with LG.

[@TECTubefilms]

We are not very familiar with LG or Mitubishi at our office, but we have not experienced those issues with brands we have used over the past 12 years, which include Carrier, TOSHIBA-Carrier, Bryant, SANYO, and Panasonic.

[@david10p]

Thank you for this video - really valuable information in here, and very well presented!

[@rodgraff1782]

I thought there were limitations on how much and what type of refrigerants that could be circulated thru a building in case of fire. Seems like a nice system, until you have a running burnout, that would require a complicated clean up. Has anyone experienced a bad compressor burn out on a large VRF system, and how did you deal with cleaning it up?

[@TECTubefilms]

Local codes do have limits on how much refrigerant of certain classifications can leak into certain types of spaces. Most of these codes are based on ASHRAE Standard 15. We suggest you watch this other video from 2015 (starting at the 1 hr and 5 minute mark) to better understand how this applies to VRF systems. kzbin.info/www/bejne/nXOyiaqPop6ljpY

[@TECTubefilms]

We have been doing VRF systems at our office since 2008 and none of those installations have experienced a compressor burnout. Burnout is generally causes by high temps in the discharge or motor windings and since most inverter compressors have extra sensors and controls to babysit things like that, it is more likely the system would lock out in those situations instead of continuing to run and damage the compressor. Additionally, since an inverter compressor seldom operates at 100%, there is less waste heat coming of the motor windings in general.

[@shenoyglobal]

Would you suggest a Hybrid VRF system in Florida for a 2+1 REsidential use. If so what make and manufacturer do you suggest.. I have heard good review on Mitsubishi

[@TECTubefilms]

All of the projects we are involved with are in the Midwest so we don't have much expertise in your climate. In general, VRF is not the best fit for residential unless the home is massive. Multi-zone ductless with variable speed inverters is better utilized in residential applications than VRF. Cost and install are lower.

[@TECTubefilms]

In regards to brands, we rep Toshiba and Carrier VRF so we are a little biased toward them

[@shenoyglobal]

@@TECTubefilms is it not the best fit for residential use because of cost and install or are there any other reasons Also residence is 7000 sq ft

[@TECTubefilms]

@@shenoyglobal One of the biggest advantages of VRF in our climate is heat reclaim mode where it sends heat from the interior zones (which need year round cooling) to the perimeter zones which need heat in the winter. A residential home does not need that in any climate. Non-heat reclaim style VRF is also not usually first cost effective for small tonnage applications which a 7,000 ft2 residence would be. Additionally, VRF pipe sizing and layout is more complicated that ductless mini-split or other systems. You need a more sophisticated contractor who has done multiple VRF installs and you are not their first customer. As with all system choices, it all comes down to what you are comparing it to. If the home already has duct systems, then replace the old A/C units with residential inverter driven variable speed A/C units that tie to variable speed fan coils and existing ductwork. If there is no ductwork, then consider inverter driven variable speed mini-splits units that allow multiple indoor units just like VRF. What advantage do you believe that VRF would have over those two types of systems in a residence?

[@claudiagonzalez8686]

Thanks for your videos

[@youcefcherraba5905]

thanks for the knowledge you dropped, and i'd appreciate any printables you might have to help me with my graduation paper

[@TorPid9]

Is there any continuity plan with this system, supposedly if the machine breaks down that mean all indoor machines go down with it unlike independent units... My question is, can we have an standby unit along with main unit?

[@TECTubefilms]

You can have multiple outdoor units connected together on the same refrigeration network. So if one outdoor unit had a failed inverter or damaged circuit board, for example, the other unit could still be operating. Not sure if that was your question or not.

[@stephenking7660]

Very well explained

[@tuantang3906]

Thanks for the video

[@aceahmad6795]

Please Post a video for compressor replacement method and how to check defective compressor

[@TECTubefilms]

Other than the inside of the cabinet being fairly space constrained because of all of the extra piping in there, replacing a compressor on a VRF system should really be no different than replacing one on a regular system.

[@aceahmad6795]

@@TECTubefilms thank you so much Sir for your reply but I mean how to flashing the system if compressor 2 is still working but compressor 1 is showing ground

[@TECTubefilms]

@@aceahmad6795 We just asked our trainers and they don't have a video in their library for that. It is, however, the exact same process for a non-VRF system that has multiple compressors on the same refrigeration circuit. Nothing special because it is VRF.

[@aceahmad6795]

@@TECTubefilms okay sir thank you for your kindly support

[@derrickgarcia303]

On the 2 pipe VRF heat recovery. Is one pipe liquid and one suction?

[@brlinf06398]

idiot, one pipe is always liquid but the other one can change between suction and discharge

[@gkairconditioner9858]

Best toshiba carrier vrf unit, I installed 44/ 54 h P unit good quality

[@gkairconditioner9858]

Thanks dear

[@hondoshaver7651]

Wow, that's a sweet technology but seems like it could be a troubleshooting nightmare o.O

[@workingshlub8861]

not really....as long as you have the software ...mitsubishi makes a good system

[@petereyes2002]

You have class information

[@merajahmad8976]

I am vrf technician specialist in toshiba vrf I remember your language in about of vrf

[@jsmitty4675]

I know this video is old but what is the process for pressure testing the unit and evacuation of the system. I'm just started on my first one today

[@sincityhvacr]

do u have any online classes for these vef units

[@TECTubefilms]

April 6 - us02web.zoom.us/webinar/register/WN_YJ9kl-vvRZWzgAS5FNs9nA

[@brijeshgurjar1935]

Please share carrier vrf gas recovry setting

[@abdullah_q8171]

Nice, but very expensive ..

[@TECTubefilms]

Expensive relative to what?

[@abdullah_q8171]

@@TECTubefilms price VRF expensive

[@abdullah_q8171]

Wich gas is butter R22 or 410 package? In my country still selling R22.. What you recommend for me to go with?

[@TECTubefilms]

@@abdullah_q8171 The price of VRF compared to what other type of system? Compared to individual ductless systems? Compared to a chiller and fan coils? Compared to ducted VAV air handlers?

[@TECTubefilms]

@@abdullah_q8171 Our answer may be biased because we have been using R-410a since 1996 and we completely stopped using R-22 equipment in our country back in 2010. In fact, we are getting set to start the phase-out of R-410a and move to R-454B and other refrigerants that are even safer for the environment.

[@FlyEaglesFly19111]

We have used a different brand and if one unit shuts down it takes out the whole VRF. have not yet used Carrier.

[@Justaguy0420]

What manufacturer did you guys use? LG will do this if you lose a head. Mitsubishi won’t. Mitsubishi’s power for its comm line comes from the ODI while if someone turns power off to a head of LG the whole system will go down.

[@TECTubefilms]

It will depend on why it shut down AND how you piped it AND if you by unit you mean indoor or outdoor.

[@FlyEaglesFly19111]

Samsung is the brand. Yes if say 1 indoor unit looses power it stops the whole system. As the Samsung is daisy chained. So each board HAS to be energized to make the system work.

[@Aabidmehraj]

Will good thing is Toshiba system will not stop if any unit losses power.

[@MeltingSkyline07]

One indoor unit kills power and whole thong dies? wtf

[@gilsoncampair5861]

Boa noite! Sou instalador aqui em São Paulo (Brasil ) estou precisando de peças vocês consegue nos fornecer?

[@TECTubefilms]

Não, desculpe. Só podemos distribuir equipamentos e peças em determinadas áreas dos Estados Unidos.

[@hesuschrist9527]

6 ton vrf perfect for 800sq apartment

[@TECTubefilms]

Haha... for most climates 6 tons would perfect to share for an entire apartment building with six 800sqft apartments

[@MeltingSkyline07]

​@@TECTubefilms is 6ton 8 hp

[@TECTubefilms]

@@MeltingSkyline07 what do you mean?

[@MeltingSkyline07]

@@TECTubefilms I wanna know if 6ton and 8hp are the same

[@TECTubefilms]

@@MeltingSkyline07 We suppose you could convert tonnage to horsepower, but no one ever speaks of cooling capacity in terms of horsepower (at least no in the US). We just converted it (actually converted tonnage to kW and then kW to hp) and 6 tons of cooling is 28.3 hp. Why do you need to know it in terms of hoursepower? What are you trying to figure out?