Compressors system Designing 919825024651

1. Contents
 VRF Technology
 Set-free ODU Product line up
 Set-free IDU Product Range
 Ref. piping Design Concept
 ODU selections

2. What is Set Free?
• Brand name given by Hitachi to its
VRF (Variable Refrigerant Flow)
DX Air-conditioning system.

3. 3
How Variable Refrigerant Flow
Achieved?
Variable Compressor Rotating
Speed using Inverter technology
Electronic Expansion Valve
Opening Control

4. • Each ODU has One inverter compressor is with
Variable speed & other compressor are fixed speed.
• Each IDU has Electronic Expansion valve, which
varies its orifice opening based on the heat load in the
respective room / area & allows only the desired
refrigerant to flow thru the cooling coil.
• ODU microprocessor controller receives continues
command from each IDU controller on the refrigerant
requirement & based on these commands, inverter
compressor increase / reduce its speed to match the
optimized refrigerant flow.
How Variable Refrigerant Flow Achieved?

5. ON
Standby
ON ONStandb
y
20% 20% 20%
20%
40%
60%
80%
100%
Outdoor Unit CapacityOutdoor Unit Capacity
∥∥
60%=20%×3 Indoor Units60%=20%×3 Indoor Units
↓↓
Minimized Energy ConsumptionMinimized Energy Consumption
VRF Concept

6. Cooling Mode

7. Heating Mode

8. 8
• Free & Flexible to IDU Model SelectionFree & Flexible to IDU Model Selection
• Energy Saving (Efficiency)Energy Saving (Efficiency)
• Easy & Flexible Designing/InstallationEasy & Flexible Designing/Installation
• Product ReliabilityProduct Reliability
• Low Noise LevelLow Noise Level
• Various Remote Control SystemsVarious Remote Control Systems
HITACHI SET-FREEHITACHI SET-FREE

10. 10
HITACHI Scroll CompressorHITACHI Scroll Compressor
In 1983, HITACHI Produced 1stIn 1983, HITACHI Produced 1st
Scroll Compressor in the WorldScroll Compressor in the World

12. Features
DC Inverter Compressor
Oil Return
Pipe
Sub-Ball-
Bearing
Structure
Trochoid
oil pump
Discharge
Synchronous
motor
Roller Bearing
Suction
Asymmetric
Scroll
5% COP Ratio
Increase
Discharge
Cool

18. ●Noise Reduction Preference Mode (Optional Function)
In addition to “Night Shift”, “Noise Reduction Preference Mode”(Enforced Noise Reduction) is
adopted.
Control
Function
No.
Setting
Sound
Pressure
Level (dB)
11 Noise Reduction Setting 1 55
12 Noise Reduction Setting 2 50
13 Noise Reduction Setting 3 45
(In case of 10 HP)
■Selectable 3 Stages of Sound Pressure Level
by External Input/Output Setting at O.D.Unit PCB
*1: A range of performance and operation are limited due to enforced decreasing on rotation frequency of compressor
and outdoor fan.
*2: Above table shows approximate values. The value may be temporarily higher than indicated .
Notes for Setting:
■More Standard Function
The sound pressure level for a particular time zone can be set based on the usage environment.*1
Day TimeDay Time
* Electrical wiring work on site is required for setting.
Input Signal*
Day Time Day Time
Night Time
Night Time
Setting Example: Low-Sound Operation Only during
Night Time by using Timer
Compressor
Rotation
Frequency
50dB Equivalent Rotation
O.U Fan
Rotation
Frequency
50dB Equivalent Rotation
2 New FSXN/FSN6Q /FSNA6QSeries Features

20. Check to ensure that the refrigerant amount is adequate before test run.
Excessive or insufficient refrigerant may lead to the short-life of device,
frequent alarm occurrence or insufficient cooling / heating capacity.
7-segment
lndication
Remarks
Sufficient
Refrigerant
The refrigerant amount is sufficient.
Excessive
Refrigerant
The refrigerant amount is excessive.
Calculate additional refrigerant amount
again and collect the refrigerant using the
refrigerant collector.
Insufficient
Refrigerant
The refrigerant amount is insufficient.
Calculate additional refrigerant amount
again and charge the refrigerant.
Procedures for Judgement of Refrigerant Charge Amount.
(1) Judgement starts by pressing the PSW1
after setting DSW5-4 ON. (for prevention of malfunction)
(2) Judgement takes max. 40 minutes.
(3) Cooling operation automatically starts while judgment.
(“TEST RUN” is indicated on the remote control display.)
5.Test Run
(2) Automatic Judgement System for Refrigerant Amount
<Service Manual P1-135>

22. 4.Control Method
This
Tim
e
Last
Time
Activation
Order
Next
Time
②
③
①
①
②
①
②
③
Activatio
n Order
(2) Rotating Operation Function <Technical Catalog P1-137>
During multiple units operation, same rotation frequency of inverter compressor results
in the equivalent loads on each compressor. Therefore, compressor’s lifetime is
improved.
Inverter Compressor Rotation
Frequency Control (Example)
Rotating Operation Function for Outdoor Unit*1
Equalizing operation time of each outdoor unit leads to compressors load reduction.*2
Operated so that the
Rotation Frequency of
the inverter
compressor and① ②
are same.
Rotation
Frequency
of ②
Rotation
Frequency
of ①
②
Operating Load
1 Unit
Operation
HighLow
① ① ①
②
③
InverterCompressor
2 Units
Operation
3 Units
Operation
At the time of
compressor start-up or 2
hours has passed from
operation starting.
*1: At least 2 outdoor units are required for this function.
Notes:
*2: Comparison between with/without rotating operation function
on the same system.
Compressor
Activatio
n Order ③

30.  25 Step ODU DC Fan motor
 85 step of inverter compressor
 Back up operation function (FSNA6Q)
 Equalization of inverter run time
 Discharge Cool Inverter compressor
 Night Mode
 Judgment of Refrigerant Charge
New FSXN/FSN6Q /FSNA6QSeries Features