Here's the link to the installation instructions and submittals for that branch joint. The system will need to be addressed and the indoor units will need to have a separate 208/230V circuit. Transmission cable is 16/2 shielded cable from the outdoor daisy chained to the indoor units.

 

If you're a few months out before you get the equipment I'd also suggest looking into some training if you've never installed a City Multi unit before. If the unit is commissioned by someone who's taken the proper training your customer will get a 10 year part and compressor warranty. Without proper commissioning the warranty is 1 year parts and 7 year compressor.

 

Very good advice above.

If this is an engineered job, you may also be required to do a 24 hour 600 psi standing pressure test, as well as a 24 hour 500 micron standing test.

 

Go to http://mylinkdrive.com and find your model number, which is a PUHY not a PUYH, and look at the install instructions for piping page 10.
Be sure and flow nitrogen when you're installing the refrigerant lines. There are no filter driers on these systems and the internal screens can get stopped up without following proper installation practices. There is comm. cable from the outdoor to the indoor units and possibly to the stats if they are smart stats or a central wall controller depending on what was sold/designed. The smart stats and the AHUs and the outdoor will all have addresses you set through the dip switches.
And as 71CHOPS said a 600 PSI test and a triple evacuation that will have to be documented if you're having a factory start up.

 

In all of the vrf installs we do. We have to work very closely with the engineers (either directly or via their very specific plans). Mitsubishi should have all of this stuff speced out for you. Line sizes, lengths to Ys, lengths to units etc.

 

THANK YOU! That’s what I was thinking, but god knows that doesn’t mean anything lol.

 

Thank you. Excellent idea. I didn’t think of that. I’ll ask my salesman if training available. Ya the pumps won’t be in till Jan/Feb so I got some time. Great idea. It’s so new to me and this isn’t a regular residential system. I was thinking about having Mitsubishi tech come out and do startup for me. $900 per day. Thanks for the heads up on the warranty and class suggestion

 

I’ll do being a 24 hour pressure test period ����

 

Got it. Thanks. ���� Will do

 

Thanks everyone.All the posts were extremely helpful. Glad I posted. Thanks for the links everyone

 

when it comes to those systems, you want to do as much as possible to keep the best support. so if that's paying for classes, or paying for the startup, in the long term, that investment will be recovered.

when you jump through all the hoops for mitsubishi, they stand behind the product.

we had a site with multiple multicity units. one set of condensers experienced a check valve explosion. The units were obsolete and out of warranty, but they found some new old stock and sold it to us at cost, covered shipping etc., They didn't have to do anything for us, but I feel they went above and beyond.

 

Question? Started install yesterday. Supplier sent me condensate pumps for each indoor unit. Do I need them? I can gravity drain the units. They also sent me (4) thermostats. Does each air handler need its own or can I use (1) thermostat and daisy chain to (2) air handlers? I want each 16 ton system to have its own thermostat. They also sent me a branch kit for the indoor units and branch kits for the outdoor units as well. I’m not combining the outdoor units. Each 16 ton connects to (2) 8 ton air handlers. I’m thinking my supplier just sent me everything under the sun, just so it would cover everything, cause they don’t know lol. The commercial Mitsubishi guy designed it for me, so he knew what we wanted. Assuming my salesman dud the offer I guess. They didn’t help me out yesterday I was confused for a minute. Appreciate ALL your replies and the help BIG time everyone. I hopped online to read the branch kits instructions you sent ����

 

Good to know. Yes I’m going to follow the warranty advice fer sure now