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Ultra Efficient & Comfortable HVAC - Mitsubishi VRF System Tour

The Mitsubishi VRF System is an extremely efficient and high-performance HVAC solution. In this video, Matt Reisinger, master builder, and Kristof Irwin of Positive Energy take a tour of the Mitsubishi VRF that just went into this new home. Kristof's specialty is high-performance HVAC and as such, he helped design the unit that went into the new construction. Kristof introduces the variable refrigerant flow (VRF) system that varies the capacity coming out of the machine. Normally, we see American Standard 2-stage equipment and a 3-ton unit will have 36,000 BTUs and you can get down to 67% of that. The Mitsubishi, in comparison, gives full-capacity and this is a 4-ton condenser, and it will scale all the way down to 15% capacity and everywhere in between continuously. When designing an HVAC system in Texas, it's important to understand the capacity needed established and how VRF systems meet the demand of a high-performance house better than a 2-speed outside compressor. The Manual J is a peak load calculation representative of the peak heating and cooling loads in this climate. On an ongoing basis, it won't see loads that high. The VRF equipment has the ability to vary the capacity to meet the part load conditions efficiently. When designing a standard HVAC system, it is designed for the worst day possible. However, the air conditioner does not need to constantly run at 36,000 BTUs. It will seldom need full capacity. It likely needs full capacity for 1% of the hours of the year, or 87.6 hours a year. VRF systems help in two areas. A normal outdoor condenser will draw something around 100 amps scaling down to 40s for running load amps. The VRF will have a soft start all of the time. It will kick on around 2 to 4 amps then ramp up as needed, with an upper limit of approximately 24-26 amps. That's a huge difference. The VRF is pretty silent, maybe a few decibels. As far as comfort goes, the VRF has the ability to control delivered capacity and can meet indoor heating and cooling needs very precisely, keeping the indoor temperature steady. Standard machines will come on at full capacity and exceed the setpoint temperature and then shutoff to wait for the setpoint to be low then come back on again, overshooting. A lot of the need for dehumidifiers in Texas is based on the design of AC systems for the worst day of the year.The systems are sometimes referred to as mini splits and some don't like those systems on the wall. There are many types of ducted equipment that can be used on the machines. It's possible to have one system for the whole house tied to a compressor on the outside, however, it still has a variable capacity ECM motor on the inside and the VRF on the outside. It can reside in a mechanical closet, just as a standard unit would. Energy savings with the VRF system are between 20 to 40%. Look into a VRF system, it's top of the line in comfort, versatility, and cost savings.