Publication date: copy write January 2017 written material by Myles Opheim

DAIKIN Hydraulics

Word through the grapevine is that specific Daikin models are factory supported for 6-8 years. The "6" and "7" series hydraulic chillers broke this corporate rule-of-thumb because they were development programs for the "8" series and use of R-410A. As of this writing (2017) Daikin hydraulics is manufacturing the "9" series.

1. A breakdown of Daikin's changes on the predominant models follow:

The "series" designation was introduced into the North American market in the 1980s with generation "3" and Daikin hydraulics has progressed up through (examples) AKS-103 / AKS-104 / AKS-105 which were all on-off-on constant speed compressor models using R-22. Note: AKSJ, AKM, AKD and other model designations exist. The next introduction among model changes arrived with the variable speed compressor designs.

An example is AKZ-106 which was an invertor duty (variable speed) AC compressor with R-22 refrigerant. AKZ-327 was an invertor duty (variable speed) DC compressor design using R-407C.

2. kilowatt Cooling Capacity versus Compressor Motor Horsepower model number designations:

The AKZ-328 family became their first variable speed DC compressor using R-410A. The AKZ-327 was invertor duty AC but the first designation of kw/hour cooling capacity in the model number. The current (2017) model production (2017) became available in the than the AKZ-329 with DC variable compressor and R-410A available

approximate 2010/2011 time frame

Reference: JIS Z8601 two digit cooling capacity (2 digit x 10)

AKZ-148 (14 x 10 = 140 kilo watt/hour)

AKZ-328 (32 x 10 = 320 kilo watt/hour)

AKZ-438 (48 x 10 = 480 kilo watt/hour)

AKZ-568 (56 x 10 = 560 kilo watt/hour)

AKZ-908 (90 x 10 = 900 kilo watt/hour)

3. Compressor Motor Horsepower Model Numbers (.33, .54, 1.0, 2.0, 3.0)

Chillers Described By Series "1,2,3,4,5,"

3a. PAST: AK~~3 is no longer built or factory supported as of this entry (2017). The series utilized R-22, had constant speed one (1) phase hermetic compressors, a capillary tube expansion device, and a three (3) phase circulating pump motor. If the condenser fan motor was separate from the circulating pump motor, then this fan motor was also single (1) phase. This series is one of the easiest to maintain from off-the-shelf, aftermarket parts.

3a. Design Flaw: "Close coupled" keyway shafting connection on circulating motor and pump. This made things OEM.

3b. PAST: AK~~4 is no longer built or factory supported (2017). Because it is so similar to the series "5" one can almost exclusively substitute "5" parts unless circuit board components vary. The "4" series utilized R-22, had a constant speed three (3) phase hermetic compressor, a capillary tube expansion device, and a three (3) phase circulating pump motor. Some of the replacement parts were obtained through aftermarket contacts.

3b. Design Flaw: "Close-coupled" keyway shafting on circulating motor and pump for closed loop applications.

3c. PAST: AK~~5 is no longer factory built or supported (2017). The North American representative's claim was that the factory would do so until 2012.

The "5" series utilized R-22, had a constant speed three (3) phase hermetic compressor, a capillary tube expansion device, and a three (3) phase circulating pump motor on the "closed loop" models.

3c. Design Push: "Close-coupled" keyway shafting on circulating motor and pump were changed out to "common shaft" designs relative to the pump and motor. That means replacement with a complete

assembly. This author is unaware of any "5" series models that may have the condenser fan motor separate from the circulating pump motor.

4. kilowatt cooling capacity Model Numbers ("6,7,8,9" designations)

Chillers Described By Series "7,8,9"

CURRENT: AK~~6 replaced the "5" series in a marketing strategy of Daikin Hydraulics.

The author does not believe that this series is being manufactured but factory support is available. The "6" series utilized R-407c which is a retrofit gas for R-22. A constant speed three (3) phase hermetic compressor, capillary tube expansion device, and a three (3) phase circulating pump motor on the "closed loop" models. Many of the parts can be obtained through aftermarket contacts. This author is unaware of models that may have the condenser fan motor separate from the circulating

pump motor. CURRENT: AK~~7 is replacing the "6" series in a marketing strategy of Daikin's. The author does not have good first-hand knowledge of this series. Factory support is available. The "7" series is believed to have utilized R-407c which is a retrofit refrigerant for R-22. CURRENT: AKS_8 is a

radical departure in marketing strategy on the part of Daikin. The "8" series utilizes R-410a refrigerant which is ozone friendly, and the refrigerant is a high pressure application compared to R-22, R-407c, and R-134a. Variable speed, direct current hermetic compressor design provides for a "throttling

effect". The expansion device is electronically controlled to enhance this " throttling ", and all control circuitry voltages are direct current. It is not known by this author what type of current the circulating pump motor uses on the "closed loop" models, nor is he aware of the models that may have the

condenser fan motor separate from the circulating pump motor. Series "8" chillers are a radical departure from low cost manufacturers who remain with constant speed / on-off operation of their product. This series will keep most customers coming back to Daikin for replacement parts as the unit ages.

Daikin customers have some nice options available in replacement of the Daikin brand.

For example:

Any brand with a constant speed on-off-on compressor operation can be utilized in your machine tool application as long as you include a reservoir (tank). This requirement is no different than air

conditioning your home or any other building. Heat gain is "matched" relative to the reservoir by starting and stopping the compressor to pre-determined temperature bands.

In machine shop applications a 3-phase compressor allows for unlimited start-stop cycles in a 1 hour period so compressor life isn't compromised.

Observations:

1. Daikin Frameless Construction, bulkhead mounting photographs 1 and 2. 2. Kanto Seiki framed component mounting photograph 3. 3. Habor Precise framed component mounting photograph 4.