solving problems using variable refrigerant flo€¦ · · 2011-08-26chiller as high as 57 db(a)...

1

Solving Problems using Variable Refrigerant Flow

Today’s Agenda

• New Construction Challenges

• Renovation Challenges

• Other Discussion points

Your friendly tour guide John Brantley, PELEED AP®, CEM®

Mitsubishi Electric HVAC Commercial Area Manager

•Engineering Support

•Contractor Support

•Owner Support

•Primary lines: Mitsubishi, Carrier, Bard, Data Aire, FHP, Munters

•Works with utilities, financing, ESCO’s, ETS, others

•Largest HVAC Distributor in the Southeast

•Over 30 locations in 5 states

•Premier Commercial Distributor in southern United States

What is VRF Technology?

Variable

Refrigerant

Flow

Primary System AttributesZoning Energy Efficiency

Simultaneous Heating and CoolingMultiple Indoor Units

Integral Control System

Variable Capacity Indoor Units

7

VRF Heat Recovery Technology

Simultaneous cooling and heating

2 pipes

8

VRF Heat Pump Technology

COOLING

HEATING

New Facility Construction Challenges

• Reducing Energy Consumption• Providing Desired Comfort Levels• Reducing Maintenance Costs• Sound Level Constraints• Installed Costs

How much electricity has How much electricity has Mitsubishi Mitsubishi Electric savedElectric saved in U.S. homes over the in U.S. homes over the

last last 10 years?10 years?

21,000 HomesOff the Grid

189,000 MWH(189 Million KWH)

Saved $18.9 Millionfor Homeowners

Superb System Efficiencies• Variable Refrigerant Flow can provide energy savings

around 25 to 30% over other system types

• Using heat pump technology with COP’s greater than 2.0 at 17 deg yields tremendous heating savings

• Variable Refrigerant Flow is a proven energy saving technology as evidenced by thousands of installations

14

Optimal Comfort System

Simultaneous cooling and heating

2 pipes

Indoor Comfort Flexibility

Floor standing unitWall-mounted unit Ceiling-suspended unit


Vertical ducted unitMedium static ducted unit

High static ducted unit Low-profile ducted unit

Product Review

4-way large cassette


4-way small cassette

1-way cassette

Recommended Maintenance Schedule

Clean indoor unit air filtersRecommended every 30 days

Clean indoor and outdoor unit coilsRecommended annually

No Longer Required Maintenance

• Water Quality• Testing and Balancing• Belt Changes

• PTAC Replacement!!

How LOUD is a traditional HVAC unit?

What Does QUIET Sound Like?What Does QUIET Sound Like?

33 dB(A)Library

50 dB(A)Refrigerator

60 dB(A)Conversation

78 dB(A)Vacuum

25 dB(A)Recording

Studio

65-75 dB(A)

Residential3-ton

HVAC Unit

How QUIET are VRF Systems?

50-60 dB(A)

PTACUnit

90 dB(A)Motorcycle

As low as19 dB(A)

Indoor Unit

As low as23 dB(A)

Ducted Unit CommercialOutdoor Unit

As low as61 dB(A)

100 dB(A)Hand Drill

70 dB(A)Busy Traffic

40 dB(A)Quiet Home

75-85 dB(A)

Air-cooledChiller

As high as57 dB(A)

Single PhaseOutdoor Unit

As low as46 dB(A)

VRF Installed Cost• Proper analysis of VRF Installed Cost must

evaluate changes in all areas of construction (electrical, architectural, etc…)

• Air Cooled VRF should be comparable in first cost with WSHP

• Air Cooled VRF should be cheaper installed than four pipe systems

Renovation Project Challenges

• Limited/Insufficient Electric Service• Adequate space to install systems

Electrical Comparison• 100 ton cooling load system using 50 (2) ton

zones• In heating fan coils are providing approx 100

deg supply air temp with 70 deg RA using 2 KW/ton resistance heat and 50% airflow

• All systems are provided neutral outside air year round by a separate system

2 Pipe VRF Design• (5) 20 ton systems with (10) 2 ton ducted air

handlers per systemSystem MCA/Unit #

UnitsTotal MCA Volt/phase

Condensing Unit 49 10 490 208/3

BC Controllers 1.08 5 5.4 208/1

Indoor Unit 2.25 50 112.5 208/1

Thru Wall Unit Design• (50) 2 ton wall mounted heat pump units with

4 KW electric backup heatSystem MCA/Unit #


Thru the Wall 44 50 2200 208/1

Thru the Wall 35 50 1750 208/3

VAV Design• (4) 25 ton package rooftop units with VAV

boxes with 4 kw electric reheatSystem MCA/Unit #


25 ton Package Rooftop Unit

149.2 4 596.8 208/3

VAV Box with 4 KW electric reheat

19.2 50 960 208/1

Chilled Water Design• 100 ton air cooled chiller with (50) 2 ton, 2

pipe fan coils with 4 kw electric heatSystem MCA/Unit #


Chiller w/pumping package

489.7 1 489.7 208/3

Fan Coils 19.66 50 983 208/1

Electrical Savings SummarySystem Total MCA- 3 Ph Total MCA- 1 Ph

VRF 490 117.9

Thru the Wall (1 or 3 ph.) 1750 2200

Rooftop VAV 597 960

Chilled water FCU’s 490 983

Renovation Project Challenges

• Limited/Insufficient Electric Service• Adequate space to install systems

Space Saving InstallationSpace Required to deliver 20 tons of CoolingSpace Required to deliver 20 tons of Cooling

Ducted 20 tons40″ x 20″ Supply Duct

Ducted 20 tons30″ Round Supply Duct

11/8″ Liquid11/8″ Gas

3″ CHW supply3″ CHW return

VRF 20 tons

Chilled Water20 tons

Rooftop Equipment Layout

CMWSHP 4-PIPE

VAV

RTU & S/S

80 ton Systems80 ton Systems

Rooftop Equipment Layout

Mechanical Room Not RequiredMechanical Room Not Required

Primary System AttributesZoning Energy Efficiency

Other Application Opportunities• Ductless Systems• Projects requiring fast installation• Projects considering using geothermal equipment • Projects involving phasing/tenant buildout• Chilled water/4 pipe designs (operation flexibility )

Other Discussion Points• Outside Air Introduction

• Dehumidification Control

40

Thank you for your time!

Questions?

www.mehvac.com

solving problems using variable refrigerant flo€¦ · · 2011-08-26chiller as high as 57 db(a)...

Documents