Installed VRF to replace traditional furnaces & ACs?

FStephenMasek

Have you installed VRF systems to replace traditional furnaces and ACs? I first saw a VRF at a friend's new home - one unit outdoors, one line-set, and multiple zones in the three story structure. The whole system in my primary residence is 25 years old, so I know I should be planning. I've replaced one contactor, and the draft inducer assemblies, but it has otherwise been reliable. The place faces west, so the two rooms in the front upstairs are the hottest, so the ducts were re-done to put those front two bedrooms, the laundry room, and a bathroom on one system, and the master bedroom and downstairs on the other. Perhaps replacing the central systems two zones upstairs, and two or three zones downstairs would be a good idea. Running new line sets would be difficult, so have you had much luck re-using line-sets?

ratio

It was almost certainly a multi split, not a VRF. Similar, but not the same.

Pros & cons to them for sure. When they work good they're great—but when they don't, they're horrid. And expensive. And hard to work on.

mattmia2

Has the manufacturing problem with copper tubing been solved yet?

Mad Dog_2

Matty? Is it poor quality copper?  Mad Dog 🐕 

FStephenMasek

ratio said:

It was almost certainly a multi split, not a VRF. Similar, but not the same.

Pros & cons to them for sure. When they work good they're great—but when they don't, they're horrid. And expensive. And hard to work on.

Our friend's new home does not have a mini-split, as there is one line-set, not multiple line-sets.

GGross

that is not enough information to identify it as a VRF. Some mini splits use a single lineset from the ODU that connect to a branch distribution box, that each indoor unit attach to. Some use a single lineset from an ODU to a single central air handler. VRF systems are extremely uncommon in residential, the main difference is that it can run heating and cooling simultaneously from a single ODU running multiple IDU.

Generally a VRF will have 3 refrigeration lines.

If you do not want to run heating and cooling simultaneously from a single ODU, I would advise against a VRF.

Many people just refer to large inverter ODU as VRF, but they are not actually VRF

That being said there are some light commercial VRF systems that could be installed residentially if you need to run heating and cooling at the same time

https://lghvac.com/commercial/product-type/?productTypeId=a2x44000003XR0O&iscommercial=true&class=Outdoor Units

Note that LG inverter mini split ODU look almost identical to these light commercial VRF units.

mattmia2

Mad Dog_2 said:

Matty? Is it poor quality copper?  Mad Dog 🐕 

I have a stack of 3 dehumidifiers with evaporator leaks that say it was still a problem around 5 years ago.