Zoning with Variable Speed Mini-Split Systems Fujitsu Service Training
Welcome - Thank you for attending Did you know? In 1940 only 42% of homes in the US had central heating In 1970 20% of homes had central Air conditioning Today, more than 70% of homes in the US have central A/C
Standard Efficiency High Efficiency The HVAC industry and consumers have always been a little slow to adopt to new technology. Consumers have invested in what s fun and not in saving $ However, the way we heat and cool our homes is changing. Why? COST fuel and delivery costs are skyrocketing Value vs. Payback Environmental conscience
HVAC Technicians Have been conditioned to accept things the way they are even if they ideas are outdated Furnaces and boilers are what we use to heat. Home Air-conditioning is made up of: A box outside tied with refrigerant pipes to a box inside. It needs to be bigger than the space really needs (just in case) Oversizing will reduce the efficiency and comfort of an HVAC system.
HVAC Technicians If a teacher tells you: it needs to be sized correctly by measuring and calculating It needs to be a matched combination with correct refrigerant pipes The ductwork has to be sized and insulated properly for its length and the cfm required for the room(s) It needs to be installed based on the installation instructions With a shrug of your shoulders, you may say: It Is What It Is
What else is often heard 13/14 SEER is still high efficiency Really? Or is it just It IS What It IS? Fujitsu General America, Inc. Copyright 2010
It IS What It IS? Really? SEER Energy Saving by the percentages - - - - - - - - - - - Potential Losses - - - - - - - - - -32% +48% - - - - - - - - - - - Potential Savings - - - - - - - - -
It IS What It IS? Really? HSPF Energy Savings by the percentage - - - - - - - - - - - Potential Losses - - - - - - - - - -38% +30% - - - - - - - - - - - Potential Savings - - - - - - - - -
www.eia.gov Government heatcalc.xls Fuel Type Fuel Unit Fuel Price Per Unit (dollars) Fuel Heat Content Per Unit (Btu) Fuel Price Per Million Btu (dollars) Heating Appliance Type Type of Efficiency Rating 4 Effiency Rating or Estimate 5 Approx. Efficiency (%) Fuel Cost Per Million Btu (dollars) Fuel Oil (#2) Gallon 3.84 138,690 $27.66 Furnace or Boiler AFUE 78.0 78% $35.46 Electricity KiloWatt-hour 0.12 3,412 $35.17 Furnace or Boiler Estimate 96.0 96% $36.64 Air-Source Heat Pump 6 HSPF 6 12.5 366% $9.60 Geothermal Heat Pump COP 3.3 330% $10.66 Baseboard/Room Heater Estimate 100.0 100% $35.17 Natural Gas 1 Therm 2 $1.12 100,000 $11.25 Furnace or Boiler AFUE 95.0 95% $11.84 Room Heater (Vented) AFUE 65.0 65% $17.30 Room Heater (Unvented) Estimate 100.0 100% $11.25 Propane Gallon $2.81 91,333 $30.79 Furnace or Boiler AFUE 78.0 78% $39.47 Room Heater (Vented) AFUE 65.0 65% $47.37 Wood 3 Cord $200.00 22,000,000 $9.09 Room Heater (Vented) Estimate 55.0 55% $16.53 Pellets Ton $250.00 16,500,000 $15.15 Room Heater (Vented) Estimate 68.0 68% $22.28 Corn (kernels) 3 Ton $200.00 14,000,000 $14.29 Room Heater (Vented) Estimate 68.0 68% $21.01 Kerosene Gallon $4.17 135,000 $30.91 Room Heater (Vented) Estimate 80.0 80% $38.64 Coal (Anthracite) Ton $200.00 25,000,000 $8.00 Furnace/Boiler/Stove Estimate 75.0 75% $10.67 http://www.eia.gov/
Zoning
Have you seen this? Can homeowners save money on utilities by using an electric heater? YES BUT They have to turn OFF their central heat and ONLY heat the room they are IN! An Inverter Mini-split heat pump can be 3-4 times* more efficient than an electric heater * Based on Heat pump COP or HSPF calculations and region.
It IS What It IS? Really? So Zone The Ductwork Right? - Added material cost $$$ - Added labor $$$ Will ducted zoning save money on the utilities? Not like you want it to: - Added duct loss $$$ - Bypass losses $$$ - Equipment cycling $$$ In fact California is currently expected to eliminate Zoning Bypass as an option
Duct loss is minimal Really? Or is it just It Is What It Is?
What statistics are available? Central Air DOE says 25-40% duct loss. Worse if ducts are in hot or cold attics SEER doesn t account for duct loss. Delivered Efficiency is what you really pay for. Ductless Under 5% cooling loss in 230 of insulated refrigerant lines SEER includes up to 25 of insulated refrigerant lines in ductless and central systems
What Variable Speed Zoning with Why cool spaces your not using? Heat or Cool up to 8 individual spaces 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Mini-Splits Does for Efficiency Wasted Energy from an On/Off Controlled Central Air System Quality Variable Speed DC Inverter Multi-Zone and Flex-Zone Systems Kitchen Living Bed-1 Bed-2 Dining HFI Condition only those areas being utilized while saving money Save up to 30% or more
What s not in the SEER? Variable speed unloading means True Inverter Minisplit products are more efficient than the SEER label indicates SEER is tested at 100%, 75%, 50% and 25% or 4 parts unloading. A quality Quad Multi Split has unloading in increments down to about 7% of it s total capacity AHRI 210/240 SEER Test 100% 75% 50% 25% Quad-Split Performance 100% 75% 50% 25% 7%
What s not in the SEER? Variable speed unloading means True Inverter Minisplit products are more efficient than the SEER label indicates SEER is tested at 100%, 75%, 50% and 25% or 4 parts unloading. A quality Quad Multi Split has unloading in increments down to about 7% of it s total capacity AHRI 210/240 SEER Test 100% 75% 50% 25% Quad-Split Performance 100% 75% 50% 25% 7%
THE WRITING IS ON THE WALL Are You Up to Speed On Variable Speed?
Cooling Solution Provided by the homeowner Split systems to address 2 nd floor (2) Mini-Splits deliver 25 SEER into the space Abandon attic ducting / 2 nd floor zone Tripled to quadruple cooling efficiency
Heating Solution Provided by the homeowner Doubled heating efficiency Offered zoned solution 15RLS on main floor Furnace used as backup heating <20 degrees
NEW systems - higher SEER than ever before! 16.1 EER 27.2 SEER 12.5 HSPF Slim Designs Combined With High Performance
High Performance Heating High Heating Capacities at low outdoor temperatures Many units are designed to operate in heating and cooling down to -5º F
Outdoor Temperature A 12,000 Btu Model Actual Heating Capacity Ratings 17,500 14,000 Btu s at 23-5 F Indoor Target Temperature 70 F TC=Btu
Common Multi Systems (2,3,4 indoor units)
Multi Systems Mix-n-Match Combinations 2,3,or 4 units can connect with refrigerant pipes directly to one outdoor unit Multiple pairs of service valves
Flexi- Multi Systems (up to 8 indoor units)
Flex Systems Mix-n-Match Combinations 2-8 units can connect with refrigerant pipes through Branch Boxes to one outdoor unit
What s New? Classic Multi Indoor unit capacity cannot exceed the rated capacity of the outdoor unit New Flexible Multi 80-130% capacity 39,000 to 62,000 of indoor unit connectable capacity. The unit is rated for 48,000 Btu. The capacity of the combined indoor units can be greater than the systems capacity System planning required careful unit & pipe layout
Flexible Multi Systems Install in limited spaces Compact and light-weight design Easier to bring to job site Easier to position and hide unit Wall Mounts Compact Cassette Slim Duct Units 3-Zone Primary Branch Box 3-Zone Secondary Branch Box Outdoor unit 36 inch 14.5 inch 38 inch Separation Tube Assembly kit
2-3 Zones Primary
4-6 Zones All refrigerant pipes and connections MUST BE INSULATED Separately Secondary Primary
7-8 Zones Secondary 2 Secondary 1 Primary All refrigerant pipes and connections MUST BE INSULATED SEPARATLEY
Electric Motors and Power DC Variable Speed
An A/C Motor Turns Due To Electro- Magnetism A rotating magnetic field is created by energizing sets of wires wound around steel cores. Alternating Current Motor Alternating Current supplied to the windings causes rotation. A standard 115 AC motor operates at 60 cycles (60 Hz) per second. The motor must be wound to run at its: Frequency Voltage Speed / RPM
A DC Motor Turns Due To Magnetism & Electromagnetism Permanent Magnet Rotor DC inverters use special chips to create DC power pulses. A Direct Current Motor A control board controls the frequency or number of times per second that the pulses are sent to the windings. The motor can be wired for a wide range of speeds and DC voltages
How Does It Work In simple terms: Alternating Current (A/C) power provided by the power company must be converted to direct current (D/C) power. Cause rotation of the motor by creating pulses of DC power directly to each winding. The motor speed / RPM is controlled by varying the number of times per second power is sent to the windings
How Does It Work #1 AC Sine Wave depicts AC current Frequency (left to right- 2 boxes = 1/60 th of a second) and voltage (up and down) #2 PWM Pulse Width Modulation is a square wave where the pulses of DC power are "made to happen" at the required voltage and frequency to make a motor spin at a given speed. Very efficient #1 1/60 th of a second 0 Volts #2 0 Volts
How Does It Work #3 Three(3) phase A/C power is a sequence of 3 out of phase equally spaced sets of pulses that create more efficient power to a motor wound with 3 sets of windings. #3
How Does It Work #4 When powering an inverter compressor the controller creates 3 phases of Pulse Amplitude Modulation (PAM) #4 Single phase A/C 208-230 power supply is provided to the equipment Simulated sine wave showing 1 phase PAM
Input power (W) Efficiency (%) Why DC? - Fan Motor Example Drive circuit PCB Fan Motor 200 160 120 80 40 0 FGL DC (New) DC motor FGL DC AC motor (Old) AC power AC motor 12 14 18 24 Torque Model range
Input power (W) Why DC? - Fan Motor Example Drive circuit PCB Fan Motor 200 160 120 80 40 0 FGL DC (New) FGL AC (Old) AC power 12 14 18 24 Model range
Why is the DC Motor more it efficient? DC Motor AC Motor No extra power required for magnetization (permanent magnet) Higher Efficiency : Rotor slipping does not exist Rotating magnetic field and rotor speed match each other. Higher Efficiency : Easy to tune to proper capacity Motor rpm can be controlled at proper revolution in order to provide the best efficiency and reduce losses. Higher Efficiency : Power required to electromagnet the rotor Lower Efficiency : Due to slipping, high rotation loss Revolving magnetic field occurs when voltage is applied to stator. Induction current flows to rotor & it rotates. Rotation speed lags behind magnetic field. Lower Efficiency : Not possible to adjust to proper capacity Due to fixed speed motor design. Lower Efficiency :
Inverter Technology
DC Variable Speed Inverter An inverter controls the operating speed of a DC motor by controlling the frequency and voltage of the power supplied to the motor. Compared to a standard Hard Start compressor An Inverter Controlled Compressor starts slowly and ramps up to the RPM to provide capacity with low electrical usage When capacity is not needed the compressor RPM is decreased. This means the input power (amp draw ) decreases too, saving utility costs
S1 motor diagram with S2 S3 S4 Inverters S5 typically S6 don t have a U contactor! V V W Compressor Motor Transistor Switching time This is a typical 3 phase a 3 pole contactor. They W U use an: Inverter Controller ON OFF + - P S1 S3 S5 S4 S6 S2 N V U MOTOR Switches SW1 - SW6 are cycled Open & Closed in sequence with a DC voltage present at + and - Power is provided to the windings This provides 3 phase DC power to the compressor At the Frequency (speed the switches open and close ) the system requires to control the compressor speed. W By changing the ON-OFF cycle of the Transistors the Compressor speed is varied to meet the required load.
IPM Compressor Motor Transistor Switching S1 motor diagram with S2 S3 S4 Inverters S5 typically S6 don t have a U contactor! V V W time This is a typical 3 phase a 3 pole contactor. They W U use an: Inverter Controller ON OFF + - P S1 S3 S5 S4 S6 S2 N V U MOTOR Switches SW1 - SW6 are cycled Open & Closed in sequence with a DC voltage present at + and - Power is provided to the windings This provides 3 phase DC power to the compressor At the Frequency (speed the switches open and close ) the system requires to control the compressor speed. W By changing the ON-OFF cycle of the Transistors the Compressor speed is varied to meet the required load.
IPM Compressor Motor Transistor Switching S1 motor diagram with S2 S3 S4 Inverters S5 typically S6 don t have a U contactor! V V W time This is a typical 3 phase a 3 pole contactor. They W U use an: Inverter Controller ON OFF + - S1 S3 S5 S4 S6 S2 Switches SW1 - SW6 are cycled Open & Closed in sequence with a DC voltage present at + and - Power is provided to the windings This provides 3 phase DC power to the compressor At the Frequency (speed the switches open and close ) the system requires to control the compressor speed. V U W By changing the ON-OFF cycle of the Transistors the Compressor speed is varied to meet the required load.
Compressors Scroll DC twin rotary compressor Rotary
DC Twin Rotary Compressor Twin Rotary VS. Scroll Compressor
The Compressor is the highest power consuming component in an air conditioning system. A higher efficiency compressor saves energy. If fan motors, out of date metering devices and old temperature controls are still in use they reduce system performance & efficiency!
Electronic Expansion Valve Size comparison What is an EEV? It s a pulse motor driven needle valve. For Comparison: A TXV is a pressure and spring adjusted needle valve
EEV Function The EEV Controls the refrigerant system pressure differential! A TXV Only maintains the differential. EEV is controlled by indoor and outdoor? Refrigerant pipe temperatures Air temperatures! (Inside and outside) Pressures (on some systems) Not just on the suction pipe! (TXV) Even during low ambient conditions it can keep the pressure differential high.
EEV Function Since the system can control Speed of the compressor Size of the metering device Indoor Fan speed Outdoor Fan Speed It can Maintain Optimum Sub-Cooling And Superheat! And if Each Indoor refrigerant circuit has its own EEV Each Zone has independent capacity control! Zoning with no extra controls or Accessories!
Inverter Mini-Splits Summary Faster installation with less materials Zoning provides amazing energy savings at part load operation Faster return on investment through savings summer and winter Source of heat that costs LESS than fossil fuels much of winter
A Full Range Of Top Quality Mini-split Products 9RLS2 single zone 27.2 SEER 16.1 EER 12.5 HSPF ESP Room sensor 7day Programmable wireless Remote control www.fujitsugeneral.com Take Your Dealership HD Maker of the: Flex-Multi 2-8 Zone