Multistack MS010XC, MS015XC, MS020XC, MS050XC, MS040XC Maintance Manual

...

Download

Page 1

Modular Water-Cooled

Chillers

Installation, Operation,

Maintenance

MS010XC, MS015XC, MS020XC, MS030XC, MS040XC, MS050XC, MS070XC, MS085XC

Standard and Total Access™ Modules

Page 2

This manual provides information on the proper installation, operation and maintenance requirements for Multistack watercooled modular chillers. Follow these instructions to help ensure that the chiller performs properly. Failure to follow these instructions can signicantly aect the chiller’s performance and reliability and may adversely aect the equipment warranty.

Contents

Safety Information.....................................................................................................................................................................................3

Nameplate and Model Number Nomenclature..............................................................................................................................4

Chiller Arrangement and Components, Standard and Total Access™ Modules...............................................................5-7

General Data................................................................................................................................................................................................8

Shipping Information..........................................................................................................................................................................9-10

Clearances and Dimensions............................................................................................................................................................11-16

Piping, Flow Protection...........................................................................................................................................................................17

Pressure Relief Piping, Water Treatment Specications, Pipe Flushing.................................................................................18

Module Assembly, Standard Modules........................................................................................................................................19-21

Module Assembly, Total Access™ Modules......................................................................................................................................22

Multiush Assembly, Leak Testing......................................................................................................................................................23

Electrical Installation, Wiring, Electrical Data............................................................................................................................24-28

Frame and Enclosure Panel Installation............................................................................................................................................29

Installation Checklist................................................................................................................................................................................30

Start-Up Data Log...............................................................................................................................................................................31-32

Operation...............................................................................................................................................................................................33-34

Maintenance.........................................................................................................................................................................................34-36

Troubleshooting....................................................................................................................................................................................... 37

Daily Log................................................................................................................................................................................................38-39

This Multistack installation and operation manual will assist in the proper installation and operation of Multistack modular chillers. Review this manual carefully.

• The information and illustrations contained in this manual are generalized. Consult with a Multistack representative to address specic installation and operating details not covered in this manual.

• Good electrical and piping practices in accordance with all National and local codes must be followed.

• This equipment must not be installed near an open ame per local codes and ASHRAE specications.

• Personnel servicing Multistack modular chillers must have, at minimum, a Class II EPA certication.

• Questions regarding the content of this manual and Multistack products should be directed to an authorized Multistack representative or to the Multistack Service Department at: (608) 366-2400 or via e-mail to info@multistack.com

Planning Ahead

To ensure all warranties and a successful installation, a Factory Authorized Technician is required to perform start-up of the Multistack Chiller. If start-up is to be performed directly by Multistack, a minimum of two weeks notice is required. Please call the Multistack Service Department at (608) 366-2400 to schedule.

Multistack has a policy of continual improvement and reserves the right to change product design, literature and specications without notice.

Page 3

Safety Information

This manual includes warnings, cautions and notes.

DANGER conveys serious hazards for injury or death. WARNING indicates risk of injury or death. CAUTION warns of possible injury or damage. NOTE calls out work practices that can result in optimal operations.

Warnings, cautions and notes include:

DANGER: To avoid the risk of electrical shock, personal injury or death, disconnect all electrical power to the unit before performing any maintenance

or service. The unit may have more than one electrical power supply. Assume all electrical wires are live, energized wires. Use lockout/tag outs.

DANGER: Use extreme caution when working around electrical components, wiring and connections to avoid injury or death by electric shock. DANGER: Never remove a lockout from equipment unless you placed it there. Each person shall place his/her own lock/tag when required to isolate

an energy source. Do not start any adjustment, service or repair without verifying that the tag/lock out switch or control cannot be by-passed or overridden. Verify that the locked-out switch or control cannot be overridden. Test the equipment to be certain that the locked-out switch is de-energized and not simply malfunctioning. Press all start buttons to conrm that the equipment WILL NOT start. Conrm that the system being serviced or repaired is the system that has been locked out. Before restarting equipment, verify all tools and other items have been removed, all machine guards are in place, all electric systems are reconnected, and personnel are clear of equipment.

DANGER: During installation, testing, servicing and troubleshooting this product, it may be necessary to work with live electrical components. Only

qualied licensed electricians or other properly trained persons may perform these tasks. Failure to follow all electrical safety precautions can result in death or serious injury. All HVAC equipment must be installed per the National Electric Code (NEC) and/or all applicable state/local codes.

DANGER: Incorrect handling of HVAC equipment can result in explosions, electrical shock or re, causing property damage, injury and/or fatality. DANGER: HVAC liquids and chemicals can be dangerous if used incorrectly or if spills or accidents occur. Handle detergents and solvents with care to

avoid spills and burns.

DANGER: Danger of explosion. Refrigerant cylinders can explode causing serious injury and/or death if not handled and stored properly.

WARNING: Only qualied, licensed electricians with proper personal protection equipment should wire Multistack chillers. Injury or death my result

if not properly wired due to electric shock hazard

WARNING: Danger of electrical shock. Many types of HVAC equipment have switches and regulators with electrical current on even when other parts

of the equipment appear to be turned o. Main circuit breakers must be turned o before servicing equipment to avoid injury, fatality.

WARNING: Be sure to use lifting slings with lifting capacity to safely handle unit weight. Consult the unit’s as-built submittal drawings for unit

weight data.

WARNING: If welding on chiller water connections, use proper electrical grounding to avoid damaging the compressors or chiller controls. Never

weld directly on the heat exchanger shells. Only an authorized ASME-certied repair agency may weld directly on ASME-certied shells. After welding, an “R” stamp is required.

CAUTION: Working with HVAC equipment can be hazardous due to electricity, moving parts, chemicals, combustion and other hazards. Use safe work

habits including proper tools and personal protective equipment. Understand and heed all safety information, installation guidelines and operation and maintenance procedures.

CAUTION: Pressurized application of cleaning substances or refrigerants must be done with the correct procedures to ensure the safety of technicians

and others, and avoid property damage.

NOTE: Use correct tools for HVAC equipment installation, maintenance and adjustment. Use the correct tools to make tight connections without strip-

ping threads or breaking screws and bolts. Use accurate refrigerant and electrical meters to properly maintain and diagnose HVAC equipment.

Page 4

Multistack Water-Cooled Modular Chillers

Multistack invented the modular chiller. Multistack modular chillers are available in a wide range of capacities, and with two independent scroll compressors. Modules can be mix-matched and combined to create up to 15-module arrays and 1,275 tons of cooling capacity using environmentally friendly R-410A. Multistack modular chillers can help owners qualify for USGBC LEED points and signicant utility rebates. Multistack’s innovative modular design makes adding more capacity as easy as purchasing and installing more modules.

Unit Nameplate

The chiller nameplate is located on the front of the control panel. Use the unit model number nomenclature to identify specic features and options of an Multistack chiller module.

Total Access™ Modular Chillers

With Total Access, heat exchangers are located on the outer edges of the chiller frame to provide easy serviceability with a small equipment room footprint. Total Access options include 10- through 85-ton modular chillers.

Model Number Nomenclature

MS 050 X C or N 2 H 1 W 0 A A -410A

Refrigerant

Condenser

Evaporator

AHRI Version - if applicable

Application

Module Number ( 1 - single, 2 - multiple)

Voltage

Conguration2

AHRI Certied (C - certied, N - Not certied)

Compressor Type

Module Nominal Capacity (10 - 160 tons)

Series

B: Bristol, C: Trane Cornerstone, R: Bitzer Screw, S: Trane Scroll, T: Danfoss Turbocor, Z: Copeland scroll (old elec), X: Copeland Scroll (ZP), A: Copeland Scroll (ZR)

1- Standard, 2- Total Access, 3 - Evap extended headers, 4 - Cond extended headers, 5 - Both extended headers, V - others

A - 208/3/60, L - 230/3/60, H - 460/3/60, C - 575/3/60, D - 200/3/50, E - 400/3/50, F - 380/3/60, S - 220/230/1/60, V - other

A - Air Cooled split, C - Single module temp controller, D - Cond unit, F - Fluid cooler (high temp),H - Heat recovery, R - Heat pump, W - Water cooled

A - Brazed SS, B - Brazed SMO, C- S&T copper, D - S&T cu-Ni, V - Other

A - Brazed SS, B - Brazed SMO, C- S&T copper, D - S&T cu-Ni, E - Double wall brazed, V - Other

Page 5

Standard Modular Chiller Arrangement

High Voltage

High Pressure

Transducer

Panel

Scroll Compressors

Low Voltage

Panel

Unit

Nameplate

Isolation/Disconnect

Switch

Buss Bar

Duct

Leaving

Condenser

Water

Header

Entering

Condenser

Water

Entering Chilled

Water Header

Evaporator

Low Pressure

Transducer

Liquid Line Sight Glass

Header

Leaving Chilled

Filter/Strainers

Water Header

Total Access™ Modular Chiller Arrangement

Multistack’s Total Access option makes maintenance and serviceability even easier by placing heat exchangers at the outside of the module frame. Manual i

Access units only) between the heat exchangers and water supply mains for heat exchanger isolation and removal without the need to remove a module or shut down the entire chiller while allowing access to all serviceable components.

Low Voltage

Panel

High Pressure

Transducer

Condenser

solation valves are factoryinstalled (Total

High Voltage

Panel

Isolation/Disconnect

Switch

Buss Bar

Duct

Evaporator

Condenser

Expansion

Valve

Scroll Compressors

Low Pressure

Transducer

Isolation

Valve

Expansion

Valve

Filter/Strainers

Condenser

Page 6

Chiller Components

Master Control Panel

Each chiller has a master control panel that can be mounted on top of any of the module panels using provided knockouts. Sensors, cables and wiring connect through the bottom of the master control. The master control box includes built-in terminal strip inputs for ow switches, start/stop signal, alarm output, and power phase monitor. As shipped, the Master Control also contains the pLAN communication wire to be eld installed by the start-up technician. Four temperature sensors and sensor wells are supplied by Multistack: entering chilled water, leaving chilled water, entering condenser water, and leaving condenser water. The sensors are to be installed in customer’s piping system.

Module Control Boards and Low Voltage Panel

The module control boards communicate individual module temperatures and pressures to the master control. Each module has a switch labeled Auto/ O/ Manual. Normal operation is in the Auto mode. If there is a problem with the master control, the selector switch can be changed to Manual to provide individual module leaving chilled water temperature control that was pre-set at the master control.

Module High Voltage Panel

The high voltage panel contains each compressor’s contactor, circuit breaker, control relay and transformer. External to the panel is the single-module isolation switch to isolate the that module from high voltage supply power.

Master Controller

Module Slave

Controller

AUTO/OFF/MANUAL

Switch

Compressors, Sensors, Switches

• Standard modules use two scroll compressors with separate refrigeration circuits.

• Each refrigerant circuit has a high pressure (HP) and low pressure (LP) transducer that sends pressure signals to the module slave controller board. Each compressor also includes an HP switch with a manual reset button.

• Transducers are a 0-5V ratiometric type.

• Compressors include oil level sight glasses. Oil level should be at ⁄ - ¼ full during operation.

• Each circuit has its own leaving chilled water temperature sensor and refrigerant suction temperature sensor.

• Compressor crankcase heaters are not standard on Multistack MS chiller modules.

Chilled and Condenser Water Connections

• Water connections to the chilled and condenser side are standard 6-inch grooved pipes on MS010X through 070X, and 8-inch on MS085X units.

• The upper header on the chilled water side is entering water to the module.

• The bottom header is chilled water leaving the module.

• Water entering the condenser is on the bottom.

• Water leaving the condenser is on top.

• The entering header on both the evaporator and condenser contains a 30mesh lter strainer to prevent debris from entering the brazed plate heat exchangers. This strainer should only be used as a nal lter stage.

• Proper ltration before the module should be installed for easy access to cleaning, such as a ‘Y’ or a basket type of strainer.

Low Voltage

Terminal Strips

Low Voltage Panel

A Compressor Isolation Switch

A Compressor

Contactor

High Voltage Panel

Control Relay

Low Voltage

Circuit Breaker

High Voltage Circuit Breaker

Transformer

Single Circuit

Breaker

Control Relay

B Compressor

Isolation

Switch

B Compressor

Contactor

Page 7

Expansion Valve, Subcooling, Liquid Line Sight Glass

• Each circuit on a module has a thermal expansion valve located between the water header pipes on the condenser side. During factory run testing the valves are adjusted to maintain 10-12 degrees superheat. Check the superheat periodically to maintain this range. Subcooling should normally be in a 10-15 degree range. No external subcooler is used.

• The liquid line sight glass shows green on the indicator bulb if no moisture is present in the refrigerant circuit. Yellow indicates potential moisture.

• Sight glasses should show full during normal operation.

• Flashing in the sight glass indicates possible under-charge of the circuit.

• Refer to the unit nameplate for refrigerant charge information.

Variable Flow and Power Actuated Buttery Valves

For variable ow on the chilled or condenser water side, chiller modules must be ordered with power actuated buttery valves.

Note: The footprint of an array of standard modules will increase as

the valves add length. Total Access™ module footprint will not change.

1. Multistack recommends controlling the chiller pumps to maintain pressure dierential across the chiller, not the system. Control based on system pressure will provide erratic results.

2. Chiller minimum ow bypass for the system can be programmed in the master controller.

Expansion

Valves

Sight

Glasses

Expansion Valves and Liquid Line Sight Glasses (Standard unit.)

Power Actuated Buttery Valve

Optional Manual Isolation Valves

Standard modules are not supplied with isolation valves. Manual or electrically actuated valves may be ordered as an option from

Multistack. Total Access modules are supplied with manual isolation valves from the factory and may be upgraded to electrically actuated valves as an option. Multistack recommends exercising the isolation valves as part of annual maintenance.

Optional Hot Gas Bypass

As an option, hot gas bypass valves (Sporlan HGBE-8) can be provided for each circuit. The valve is adjustable from 75 to 150 psi with a standard setting of 120 psig. A screw on the pilot valve handles the adjustment. Turning clockwise increases the valve setting; counterclockwise rotation decreases the valve setting.

Buttery Valve Actuator for Variable Flow shown on standard module with extended headers.

Hot Gas Bypass Valve

Heat Exchanger Isolation Valves on Total

Access™ Modular Chiller

Page 8

General Data Table

MS010X MS015X MS020X MS030X MS040X MS050X MS070X MS085X

Compressor Type Scroll

Dry Weight (lbs. each) 89 135 135 146 280 293 390 419

Normal Capacity (tons each) 5 7.5 10 15 20 25 30 40

Compressor Quantity/Module 2 2 2 2 2 2 2 2

Oil Charge (pints per compressor) 3.5 6.9 6.9 6.9 9.5 9.5 13.3 13.3

Evaporator (Brazed Plate) Brazed Plate

Weight (lbs.) 50 70 70 90 180 180 220 300

Water Storage (gal.) 1.0 1.6 1.6 2.2 5.5 5.5 7.3 10.1

Circuit Configuration Dual Dual Dual Dual Dual Dual Dual Dual

Quantity 1 1 1 1 1 1 1 1

Header System (gal.) 7 7 7 7 7 7 7 14

Condenser Brazed Plate

Weight (lbs. each) 50 80 80 100 200 200 290 340

Water Storage (gal.) 1.1 2.2 2.2 2.9 6.6 6.6 10.1 12.3

Circuit Configuration Dual Dual Dual Dual Dual Dual Dual Dual

Quantity 1 1 1 1 1 1 1 1

Header System (gal.) 7 7 7 7 7 7 7 14

Refrigerant Type R410A

Charge (lbs./circuit) 6.5 6.5 6.5 10 18 20 23 28

Number of Circuits 2 2 2 2 2 2 2 2

Total Water Volume - gal./module 16.1 17.8 17.8 19.1 26.1 26.1 31.4 50.3

Operating Weight (lbs.) 1,490 (1,620) 1,500 (1,630) 1,510 (1,640) 1,610 (1,740) 1,790 (1,920) 1,970 (2,100) 2,060 ( 2,210 ) 2,350 (2,680)

Shipping Weight (lbs.) 1,330 (1,470) 1,340 (1,480) 1,350 (1,490) 1,450 (1,590) 1,630 (1,770) 1,950 (1,990) 1,890 ( 2,060) 2,380 (2,630)

NOTES: Figures in parentheses ( ) apply to Total Access™ conguration chillers. Add 75 lbs. per module if equipped with enclosure panels.

Multistack has a policy of continual improvement and reserves the right to change product design, literature and specications without notice.

Page 9

Module Shipment Package

NOTE: Before accepting delivery of the Multistack chiller, check

the overall condition of the equipment for damage such as broken copper lines, oil leaks, damaged controls and/or electrical component housing, or any major component torn loose from its mounting. If the Multistack modular chiller is damaged during shipping by the transportation company or its agent, the installing contractor MUST promptly le a claim with the transportation company and advise Multistack. Any discrepancy or damage must be noted on the bill of lading.

Pallet #1 — Typical Cabinetry Package (Optional)

1. Top Front Panel

2. Bottom Front Panel

3. Rear Panel/End Panel

4. Side End Panel

5. Master Controller Top Panel

6. Frame Pieces

7. Frame Connectors, Fasteners, Clips & Magnetic Tape

Pallet #2 — Buss Connections

8. Buss bar

9. Buss bar insulation

10. Ground strap

11. Junction Box leg

Multistack has a policy of continual improvement and reserves the right to change product design, literature and specications without notice.

Page 10

Pallet #3 — Typical Piping & Electrical Package

18. Master Controller*

19. Junction Box

20. Junction Box Cover

21. Sensors / Cables

22. Junction Box Connector (Throat)

23. Power Phase Monitor

24. Buss bar Connector

25. Power Phase Monitor Wire

26. Buss bar Insulation Overlap

27. Phase Monitor Wire

28. Buss bar End Caps

29. Drain Valves & Fittings

30. Module Joining Bolts

31. End Cap for Multiush system (upper)

32. End Caps (evap)

33. Couplings

34. Multiush pipe

35. Solenoid for Multiush system

36. Pipe Stubs

37. End Cap Multiush system (lower)

38. Filter Stops

39. Pet Cock Valves

40. Drain Valves & Fittings

41. Sensor Wells

42. 30 Mesh Filter Strainer

* May be shipped separately to sales oce or job site. ** Shipped inside #19 - Junction Box

Multistack has a policy of continual improvement and reserves the right to change product design, literature and specications without notice.

Moving Chiller Modules

Caution: Modules Are Top Heavy

Module on Fork Lift Module on Pallet Jack

Multistack chiller modules MS010 through MS085 may be moved using a fork lift truck, pallet jack or similar equipment. Optional spreader bars for lifting and factory-installed wheels are available from Multistack. Contact your Multistack representative. For unit weights see the table on Page 8 and the jobspecic as-built submittal drawings.

Page 11

Clearances

Diagram shows typical dimensions and the recommended clearances around the modular chiller. There must be a minimum of six inches clearance over the top of the chiller, including the top of master controller if installed on top of the module.

For specic unit dimensions, refer to as-built submittal drawings.

Page 12

Width (A) Depth (B) Height (C)

Module Dimensions (No Panels)

Standard 28” 47 ⁄” 64”

Total Access (MS010--050) 32” 56” 67”

Total Access (MS070) 34” 56” 67”

Extended Headers 28” 62 ⁄” 64”

Extended Headers 28” 76 ⁄” 64”

*Standardized drawing of sample customer installation

** Enclosure panels are optional

Standard Modules (Constant Flow Design)

Page 13

Width (A) Depth (B) Height (C)

Standard 28” 47 ⁄” 64”

Extended Headers 28” 62 ⁄” 64”

Total Access (MS070) 34” 56” 67”

Module Dimensions (No Panels)

*Standardized drawing of sample customer installation

**Enclosure panels are optional

Evaporators and Condensers

Standard Modules with Extended Headers on

Variable Flow Design for Chilled and Hot Water

Total Access (MS010--050) 32” 56” 67”

Extended Headers 28” 76 ⁄” 64”

Page 14

Width (A) Depth (B) Height (C)

Standard 28” 47 ⁄” 64”

Extended Headers 28” 62 ⁄” 64”

Total Access (MS070) 34” 56” 67”

Module Dimensions (No Panels)

*Standardized drawing of sample customer installation

** Enclosure panels are optional

Total Access (MS010--050) 32” 56” 67”

Extended Headers 28” 76 ⁄” 64”

Standard Modules with Extended Headers on Condensers

Variable Flow Design for Hot Water, Constant Flow for Chilled Water

Page 15

Width (A) Depth (B) Height (C)

Module Dimensions (No Panels)

Standard 28” 47 ⁄” 64”

Total Access (MS010--050) 32” 56” 67”

Total Access (MS070) 34” 56” 67”

Extended Headers 28” 62 ⁄” 64”

Extended Headers 28” 76 ⁄” 64”

*Standardized drawing of sample customer installation

** Enclosure panels are optional

Standard Modules with Extended Headers on Evaporators

Variable Flow Design for Chilled Water, Constant Flow for Condenser Water

Page 16

Width (A) Depth (B) Height (C)

Module Dimensions (No Panels)

Standard 28” 47 ⁄” 64”

Total Access (MS010--050) 32” 56” 67”

Total Access (MS070) 34” 56” 67”

Extended Headers 28” 62 ⁄” 64”

Extended Headers 28” 76 ⁄” 64”

*Standardized drawing of sample customer installation

** Enclosure panels are optional

Total Access Modules With or Without Variable Flow

Page 17

CONDENSER SIDE EVAPORATOR SIDE

Sensor Pockets, Sensors

Supplied by Multistack,

installed by others.

Pressure

Taps

Pressure

Taps

Isolation

Valves

Strainer

Flow/DP

Switch

Chilled Water

Pump

CHW In

CHW Out

To Cooling Tower or Fluid Cooler

CW Out

CW In

3-Way

Bypass Valve

Flow/DP

Condenser

Pump

Switch

Isolation

Valves

Strainer

Sensor Pockets, Sensors Supplied by Multistack,

installed by others.

Pressure

Taps

Items in This Area Included

with Chiller

Recommended Piping

All piping must be properly and adequately supported at coupling connections and suitable intervals along the piping runs. Hanger design must provide for the weight of uids in the piping system when the chiller is in operation.

Multistack modules are equipped with brazed plate heat exchangers made of 316 stainless steel. Multistack recommends use of a 30-mesh system strainer, Y-type basket or equal, in each condenser and evaporator inlet header.

It is the installing contractor’s responsibility to make sure the water systems have been ushed and the strainers are clean and clear of debris before starting the chiller. Do not ush piping so as to push debris into or through the through the chiller heat exchangers.

Important

Be sure to install the supplied sensor wells in the system piping. The wells should be installed a few feet from the chiller in the entering and leaving chilled water and entering and leaving condenser water pipes.

Typical Sensor Wells

Flow Protection

Proof of chilled water and condenser water ow is required by the Master Controller inputs. Paddle-type or Dierential Pressure (DP) switches may be used. Switches can be supplied by Multistack as an option, otherwise they are to be eld supplied and installed. Chillers purchased with chilled or condenser water pump modules have a DP switch installed across the pump to verify operation. Multistack recommends a paddle-type switch be installed in the leaving chilled water piping using a dierential pressure switch. Install it across the inlet and outlet water connections to the chilled and/or condenser water piping connections.

System Water Volume

A properly sized chilled water system must have enough time (at least three minutes) to properly control and respond to changes in load and to prevent short cycling of the chiller. To ensure the system water volume is adequate, a general rule of thumb is:

7-10 gallons of water per ton or Acceptable Chilled Water Volume = Chilled Water Design GPM X 3

If the system heat exchangers, piping and components cannot hold the necessary chilled water volume, a properly sized chilled water storage tank should be added.

Condenser Water Temperature Control

For installations where entering condenser water temperature could be lower than 65°F Multistack recommends installing a three-way tower bypass valve to maintain a minimum of 65°F entering condenser water temperature. This is based on a 10°F Delta-T system.

Page 18

Pressure Relief Piping and Refrigerant Monitoring

Multistack chiller modules use a small refrigerant charge (typically 0.6 lbs. per ton) and are often exempt from many requirements of ASHRAE 15 Standard. Pressure relief valves are not standard on water-cooled modules and must be special ordered if required by local codes.

Water Treatment / Specications

Supply water for both the chilled water and condenser water circuits must be analyzed and treated by a professional water treatment specialist familiar with the operating conditions and construction materials used in Multistack modular chiller heat exchangers, headers and associated piping. Water quality for modular chillers using 316 stainless steel brazed plate heat exchangers and carbon steel headers must be maintained within the following parameters:

Water Specications Specications with 25 Percent Glycol ph >7 and <9 ph >7 and <9 Total Dissolved Solids (TDS) Less than 1000 ppm Total Dissolved Solids 1,000 - 10,000 ppm Hardness as CaCO3 30 to 500 ppm Conductivity 1,000 - 15,000 ppm Alkalinity as CaCO3 30 to 500 ppm Hardness as CaCO Chlorides Less than 200 ppm Alkalinity as CaCO

> 500 ppm

30 - 500 ppm

Sulfates Less than 200 ppm Chlorides < 200 ppm Sulfates < 200 ppm

Pipe System Flushing Procedure

Before connecting the chiller to the condenser and chilled water loop, the piping loops must be ushed with a detergent and hot water (110-130º F) mixture to remove any dirt and organic residue. After removing residue, continue ushing with a dilute phosphoric acid, sulfamic acid or citric acid and water mixture to remove inorganic scale in the pipe. Cleaning chemicals such as Nu-Calgon “Imperial Grade” Scale Remover part number 4360-84 or equivalent suitable for both organic residue and scale removal may be substituted. Otherwise detergents and acids shall not be combined unless approved by the chemical manufacturers. Only chemicals compatible with 316 stainless steel, copper and carbon steel shall be used. (Any concentrations of hydrochloric or sulfuric acid or chloride containing chemicals shall not be allowed to come in contact with copper brazed 316 stainless steel heat exchangers).

Caution: The use of unapproved chemicals in the chilled or condenser water supplies may damage the heat exchangers. These chemicals in-

clude, but are not limited to, hydrochloric acid, sulfuric acid, muriatic acid, and household bleach. Damage caused by the use of these and other unapproved chemicals is not covered by warranty. The only approved chemicals for heat exchanger cleaning are phosphoric or sulfamic acids in concentrations of 10 percent or less by volume. For more information contact your Multistack representative.

While ushing, 30-mesh Y-strainers (or equivalent) must be in place in the system piping and examined periodically as needed to remove collected residue. The ushing process shall take no less than six hours, or until the strainers are clean after ushing. Old pipe systems with heavy encrustation shall be ushed a minimum of 24 hours and may require as much as 48 hours before the lters run clean. Detergent and acid concentrations shall be used in strict accordance with the respective chemical manufacturers instructions. After ushing with the detergent and/or dilute acid concentrations, the system loop shall be purged with clean water for at least an hour to ush out all residual cleaning chemicals.

Page 19

Module Assembly

Multistack chiller modules and multiple module chiller arrays are designed to be mounted on steel rails.

Opposite End

Same End

1. Determine the entering and leaving evaporator and condenser connection arrangement before setting mounting rails and modules modules in place. Connections may be at the same end or opposite ends, depending upon jobsite requirements.

2. Chiller modules are to be mounted on 4- x 4- x 4-inch steel rails or equivalent , 21 inches center-to-center.

4. Lubricate rails with vegetable shortening or other non-petroleum lubricant to facilitate installation.

Vibration Pads

3. Place 4- x 4- x 3/8-inch wae type vibration pads every 22 inches under rails. 50 PSI maximum loading.

Note: Seismic restraint information available from Multistack.

Page 20

Module Assembly

5. Place rst module on the rails.

7. Place subsequent modules onto rails.

6. Slide module into position.

8. Leave sucient space between modules to install coupling gaskets.

9. Lubricate gaskets with solid vegetable shortening or other non-petroleum based lubricant.

11. Install top joining bolts.

10. Slide modules together lining up footing holes. Install bottom joining bolts.

12. Starting with the lower header, install pipe couplings. Position coupling bolts at one and seven o’clock positions as shown for proper frame installation. Note: Assure proper strainer placement.

Page 21

Module Assembly

13. If adjustment is needed when tightening bolts, loosen the center header bolt.

15. Install the header blank ends, starting at bottom, then move to the top blank that includes drain valves (evaporator shown).

14. The grooved heat exchanger couplings may also be loosened if adjustment is required.

16. Install lter stop rings on module closest to piping take-o. The 9-inch long pipe stubs supplied by Multistack are to be installed at the take-o ends of the chiller.

17. The 3/4-inch drain valve (A), should be located on bottom header and petcock valve (B) installed in each contractor pipe stub.

Page 22

Module Assembly - Total Access™ Modules

Multistack Total Access modular chillers are assembled into chiller arrays in the same manner as non-Total Access modules as shown on Pgs. 19-21.

Grooved ange water connections on Total Access chiller modules joined into a chiller array.

Condenser side view of Total Access chiller modules assembled into a chiller array. .

Evaporator side view of Multistack Total Access™ modules. (Optional enclosure panels not shown.)

Page 23

Multiush System Assembly

The following procedure describes installation of the Multiush automatic debris removal system. This system is used periodically to remove dirt and debris from the from the chiller heat exchangers.

1. Attach Multiush pipe to module header pipe. 2. Insert 30-mesh lter into header.

NOTE: See Pallet #3 for Multiush components, Page 10.

3. Install large grooved pipe couplings. Leave loose - do not tighten. 4. Attach Multiush pipe ttings using grooved couplings

5. Install manual or solenoid valve at end of Multiush header.

6. Tighten all ttings.

as shown.

Leak Testing

NOTE: Before leak testing make sure the four sensor wells have been installed.

After all piping connections are complete, make a static leak pressure test and seal any leaks. When the leak test has proved satisfactory, start the chiller system pumps and purge any air from the system. Seal any remaining leaks before proceeding.

Page 24

Electrical Installation

Field wiring must comply with all federal, state and local regulations. Circuit breakers, fuses, wiring and wire size must be installed per the National Electric Code (NEC). Voltage applied to Multistack chillers must be within plus/minus 10 percent of nameplate voltage. Voltage imbalance between phases may not exceed two percent. According to NEMA Standard MG-1-1998, a two percent voltage imbalance will cause a current imbalance of six to 10 times the voltage imbalance. Voltage imbalance between electrical phases must be kept to a minimum. Most Multistack chillers come with a single point of electrical connection (up to 500 amps) to simplify installation. The main electrical conduit feeding the power junction box may enter from either the top, bottom, or left side of the panel when facing the panel. Chillers requiring more than 500 amps will have multiple electrical connection points (per the 500 amp requirement).

DANGER: To avoid the risk of electrical shock, personal injury or death, disconnect all electrical power to the unit before performing any maintenance or service. The unit may have more than one electrical power supply. Assume all electrical wires are live, energized wires. Use lockout/tagouts.

Optional Single Module Field Connection

For single module installations, the power junction box can be deleted, but a power phase monitor must be installed. The main electrical feed can connect directly to the module circuit breaker.

NOTE: There is a dedicated chiller ground in this panel that must connect to a true earth ground.

Junction Box Support Electrical Junction Box

1. Attach the electrical junction box support. Line up the orange posts to ensure support is not backwards. The threaded plate slides in between frame.

2. The electrical junction box may be installed on either end of the chiller module.

3. Remove cover plate on appropriate end of the junction box, then bolt junction box to the support.

4. Cut the junction box support leg to length and fasten to the bottom of box and then to the oor, if necessary.

5. Three-phase wire and the ground wire, sized according to the nameplate rating, should be run through the junction box.

Junction Box Support Leg

Buss bar Installation

NOTE: Contact the local Multistack representative before installing the buss bar. Depending on the start-up representative’s policy, the attachment of

the buss bar system, and power phase monitor to the electrician’s wire and lugs may be the responsibility of the electrician or the Multistack authorized start-up technician.

1. Remove the buss duct covers. 2. Remove the isolation switch cover

Page 25

3. Install the three buss bar connector wires to the isolation switch at each module. The wires are shipped with each

module.

5. After connecting the Line 3 lugs for all modules, cut the orange insulation to t between the lugs. Install the lug cover and snap the buss bar into the plastic holders.

4. Remove the orange insulation and install the buss bar for Line 3 (back). Connect lug for Line 3 on each module.

6. Single-phase power for the modules should be taken o two lines of the buss bar. Multistack recommends using

7. Follow the procedure in Step 5 to complete installation of Lines 1 and 2.

Lines 1 and 3.

8. Follow the procedure in Step 5 to complete installation of Lines 1 and 2.

9. With all three lines installed, use the provided overlap pieces to cover any open buss bar areas.

DANGER: During installation, testing, servicing and troubleshooting this product, it may be necessary to work with live electrical components. Only qualied licensed electricians or other properly trained persons may perform these tasks. Failure to follow all electrical safety precautions can result in

death or serious injury. All HVAC equipment must be installed per National Electric Code (NEC) and all applicable state/local codes.

Page 26

10. The ground bar must be drilled, then attached to the module ground lug.

11. Reinstall the buss duct and isolation switch covers. Install the main power connectors as shown.

12. Install the power phase monitor as shown. When correctly installed the lettering on the power phase monitor is inverted. Wires are run to the normally open contact of the power phase monitor and connect to the master control.

NOTE: IT IS THE ELECTRICIAN’S RESPONSIBILITY TO CONNECT MAIN POWER TO THIS CONNECTOR.

Single Point Power

On water cooled chillers with single point power, optional wire whips may be ordered and substituted for the standard buss bar. The conduit, wiring and junction box are shipped as part of the loose parts package. The wire and conduit are then connected to the junction box as the modules are installed. Each wire and circuit breaker is marked for correct connection.

Each wire and circuit breaker is marked for correct connection.

Module wiring connections to the power junction box must be completed by a qualied electrician.

NOTE: Be sure to replace all protective covers after completing wiring connections.

Page 27

Typical Interconnecting Wiring. Consult the Specic, As-Built Submittal Wiring Diagrams

Multistack has a policy of continual improvement and reserves the right to change product design, literature and specications without notice.

electrical wires are live, energized wires. Use lockout/tagouts.

Page 28

System Wire & Fuse Sizing Specications

Compressor Rated Load Amps (RLA) and Locked Rotor Amps (LRA) Data

Standard and Total Access™ Modules

RLA/LRA

VOLTAGE 208 230 460 575

MS010X* 13.1/136 11.8/136 5.9/66.1 4.7/55.3

MS015X 24.8/240 22.4/240 11.9/130 9.1/93.7

MS020X 28.1/240 25.4/240 13.9/140 10.7/107.6

MS030X 49.8/340 45.0/340 22.5/173 18.0/132

MS040X 54.0/538 49.0/538 23.5/229 19.5/180

MS050X 67.0/605 60.0/605 30.0/272 24.0/215

MS070X 89.0/599 80.0/599 40.0/310 32.0/239

MS085X 112.8/943 102.0/943 51.0/408 37.6/375

* MS010X units are also available for single-phase power (230/1/60 ) applications and have an RLA of 19.5 amps and LRA of 178 amps.

MCA

3 CONDUCTORS

1 CONDUIT

6 CONDUCTORS

2 CONDUIT

50 8 — 65 6 — 85 4 — 100 3 — 115 2 — 130 1 — 150 1/0 — 175 2/0 — 200 3/0 — 230 4/0 — 255 250 MCM — 285 300 MCM 1/0 300 — 1/0 350 — 2/0 400 — 3/0 460 — 4/0 500 — 250 MCM

(Applicable codes may require dierent wire sizing)

1. Wiring Sizing: Minimum Circuit Ampacity (MCA) MCA = (1.25 x RLA1*) + RLA2 + RLA3

2. Fuse Sizing: Maximum Fuse (MF), Type RK5 Fuse MF= (2.25 x RLA1*) + RLA2 + RLA3 Where MF does not equal a standard size fuse, the next larger size fuse should be used.

NOTES:

A. *RLA1 = RLA of the largest compressor in the system. RLA2 & RLA3 = RLA of the other compres-

sors in the system. B. Total system Minimum Circuit Ampacity (MCA) shall not exceed 500A. C. Wire sizing is based on the National Electrical Code (NEC) rating for 75°C copper wire, with 3

wires per conduit. D. Wiring distance from branch circuit shall not exceed 100 feet.

lockout/tagouts.

Page 29

Frame & Panel Installation

Attachment of the optional enclosure panels is the responsibility of the Multistack authorized start-up technician. Typical installation is shown.

1. Install panel clips and spindle posts on the outside four corners of module frame.

4. Install two long frames over spindle posts vertically in rear (buss bar side). Attach top frames to corner joints (use special frames with seven holes for end modules only). Attach 20-inch horizontal frames, two in front, one in rear.

2. Attach panel supports on outside of end modules.

3. Attach front frame section on module (33-1⁄8 -inch pieces on bottom). Use “T” connectors in front middle. The four corner connectors go on top, front and rear.

5. Once the frame is assembled, attach the black fasteners and magnetic tape (or Velcro™ strips) to front of support panels.

6. With the rst module frame and panels complete, install the additional enclosures.

Page 30

INSTALLATION CHECKLIST & REQUEST FOR AUTHORIZED START-UP ENGINEER

CUSTOMER: _______________________________________

JOB NAME: ________________________________________

JOB LOCATION: _____________________________________

CUSTOMER ORDER NO.: ________________________________

CHILLED WATER Yes No N/A

Piping complete and connected to Multistack Units. Water system lled and vented. Pumps installed (Rotation checked). Recommended strainers installed. Controls (3-way valves & by-pass valves, etc.) operable. Water system operated and ow balanced to meet unit design requirements. Strainers checked for unusual debris. Flow or dierential pressure switch installed.

CONDENSER WATER Yes No N/A

Piping complete and connected to Multistack Units. Cooling tower ushed, lled and vented. Pumps installed (Rotation checked). Recommended strainers installed. Controls (3-way valves and by-pass valves, etc.) operable. Cooling tower fans wired and operable. Condenser water system operated. Condenser & evaporator strainers must be checked, cleaned and free of debris. Flow or dierential pressure switch installed.

ELECTRICAL Yes No N/A

Power wiring complete and in accordance with nameplate rating on Multistack unit and prepared for connection in accordance with installation manual. NOTE: No power is to be applied to unit prior to inspection by Multistack engineer. All interlock wiring complete between control panel and complies with Multistack specications and with applicable codes.

MISCELLANEOUS Yes No N/A

Thermometer wells, thermometer gauges, control, etc. installed. A minimum system load of 50% of total building load is available for testing and

adjusting controls.

q q q q q q q q q q q q q q q q q q q q q q q q

q q q q q q q q q q q q q q q q q q q q q q q q q q q

q q q

q q q q q q

We understand that authorized representatives of the installing electrical and piping contractor must be available during the start-up period and that coordination is our responsibility.

We further understand that the services of Multistack Authorized Start-up Engineer will be furnished for a period of not more than sixteen (16) consecutive normal working hours and we agree that a charge for time and expenses will be made by Multistack if services are required for longer than sixteen (16) consecutive normal working hours or if repeat calls are required through no fault of Multistack.

Signed Title

Company Name, Company Location and Company Telephone

Job Location Telephone

Page 31

START-UP DATA LOG

START-UP DATE: _______________________________ SHIP DATE: _____________________________ JOB NAME: _________________________________JOB NUMBER: _____________________________ ADDRESS:_________________________________________________________________ MULTISTACK REPRESENTATIVE: ____________________________________________________ MODEL NUMBER: ____________________________________________________________

MODULE SERIAL NUMBERS

1. ____________________ 7. _______________________

2. ____________________ 8. _______________________

3. ____________________ 9. _______________________

4. ____________________ 10. _______________________

5. ____________________ 11. _______________________

6. ____________________ 12. _______________________

WATER SIDE AND INSTALLATION CHECKLIST CIRCLE CORRECT RESPONSE

1. Chiller mounted on rails and isolators? YES NO

2. Any visible damage, oil or refrigerant leaks? YES NO

If yes, detail: ________________________________________

3. All pipe work independently supported from chiller? YES NO

4. System sensor wells installed: CHILLED: IN OUT CONDENSER: IN OUT

5. Flow or dierential switches installed: CHILLED: ____ CONDENSER: ____

6. Operation of ow or dierential switches with reduction of 50%. P __________

8. Condenser 3-way by-pass valve? YES NO

If yes, Temperature set point: _____ °F

9. System strainers installed? CONDENSER: YES NO EVAPORATOR : YES NO

10. Install System sensors and apply thermal paste? YES NO

DESIGN PARAMETERS

1. ECHW ____________________

2. LCHW ____________________

3. CHW GPM ____________________

4. CHW P DROP ____________________

5. ECW ____________________

6. LCW ____________________

7. CW GPM ____________________

8. CW P DROP ____________________

ELECTRICAL AND CONTROLS CHECKLIST

1. All electrical connections tight and correct? YES NO

2. Power wiring sucient to carry F.L.A.? YES NO

3. Voltage levels: PHASES: 1 + 2 _______ 2 + 3 ________ 1 + G _______ 2 + G ________ 3 + G ________

4. Set module board addresses, run communication wire, do factory reset on Master Control? YES NO

5. Program system variable to site connections, date and time? YES NO

6. Verify demand for cooling? YES NO

7. Check temperature and pressure sensors through microprocessor display? YES NO

8. Check interlock operation: Stop chilled water pump? YES NO

Stop condenser water pump? YES NO

9. Provide training to contractor or owner? YES NO

9. Leave system in full operation? YES NO

10. Notify contractor of any problems? YES NO

Start-up Service Technician Owner or Contractor Acceptance

Page 32

Start-Up Data Log, Cont’d

Actual Setpoints

1. ECHW (Upset) ____________________

2. LCHW (Loset) ____________________

3. VSP __________________________

4. Control ________________________

5. TDIFF _________________________

6. Flush Dur. ______________________ *PC0 Program Version _________________ (Go to main menu screens then push PRG & UP buttons)

Measured Readings

1. CHW P Drop _____________________

2. CW P Drop ______________________

CURRENT TEMPERATURE

MODULE

A B C Suct LoChw SYS LCHW ECHW

Factory Setup

1. Program Type __________________ C. CHW Bypass _________________

2. Chiller Type ___________________ D. CHW Min Output ______________

3. Refrigerant ___________________ E. CW Output __________________

4. Flow Faults: CHW ________________ F. CW Bypass __________________

CW _________________

G. CW Set point_________________

5. Circuit Type ___________________ H. CW Min Output _______________

6. Variable Flow __________________ I. CW PID ____________________

A. Valve Display ________________

J. CHW PID ___________________

B. CHW Output _________________

HP LP

Page 33

Operation

The Multistack chiller provides chilled water to an external load, based on return water temperature to the Multistack Master Control. When the entering chilled water temperature sensor sends a signal to the master controller that cooling is needed, compressors will start and begin to produce chilled water. A compressor start is determined by the entering chilled water (ECHW) upper set point and the variable set point setting in the Master Control System Variables menu. When the ECHW sensor senses that the chilled water temperature has dropped below the set point, compressors will begin to cycle o.

Chiller modules equipped with modulating buttery valves on the chilled water side are controlled from the leaving chilled water set point (lower set point) in the System Variables menu. The module slave board(s) send a 2-10 VDC output to each actuator to modulate the water valve to maintain lower set point. When a module is not running, valves close to prevent bypassing water at the operating chiller modules.

For variable ow applications one or more valves may remain open at all times to provide minimum ow through the chiller. The valve that stays open will always be the lead compressor for that day, eliminating the need for an external bypass installed at the chiller. If modulating buttery valves are used on the condenser side of each module, the valves will control to a discharge pressure setting selected from the Factory Setup menu. This is also a 2-10 VDC output each module board sends to the valve actuator. If the condenser pump cycles o while no modules are running, minimum ow doesn’t need to be considered. If the condenser pump runs at minimum ow, the condenser bypass should be enabled in the Factory Setup menu.

Sequence of Operation, Leaving Chilled Water Temperature Control

The Multistack chiller is equipped with a microprocessor based supply water temperature controller. The chiller operates in response to leaving chilled water (LCHW) set points.

AUTO (Toggle switch on machine)

In AUTO mode, the compressors operate as needed to maintain the LCHW set point. Cooling temperature control with CONTROL TO: set to LEAVING is based on: LCHW SET POINT

LCHW OFFSET LCHW STAGE OFF

1. The Leaving Chilled Water (LCHW) set point default is 45 degrees F with a 35 to 80 degree ranges. The controller maintains this value within __ +/- of the LCHW Oset.

2. The LCHW Oset default is 2 degrees F with a range of 0.5 to 10 degrees. This is the value above and below the LCHW Set point that compressors are staged on and o.

3. The LCHW Stage O delay is defaulted to 30 seconds with a 5 to 180 second range. This allows for a delay between the shutting o of compressors in Leaving Chilled Water control. If the system leaving temperature drops too far too quickly (2 degrees below where the previous compressor was to shut o) the controls will allow one more compressor to shut o within that 30 seconds. That should be enough to back o the leaving temperature

so the over shoot condition doesn’t continue.

Modulating valves on the modules will control to the following in AUTO MODE:

The SYSTEM VARIABLE of CONTROL TO: Set to a value of LEAVING.

Evaporator valve will control to the LCHW SET POINT.

Variable Flow Chilled Water and/or Variable Flow Condenser Water

Motorized actuating valves for varying water ow through the evaporators and or condensers are factory installed on each heat exchanger. To accomplish VFD chilled water and/or condenser water ow the system must control the chilled water pump and/or condenser water pump based on pressure drop across the chiller. As a compressor starts a valve is opened and pressure drop decreases. The pump should then speed up to match the desired pressure drop. Control of the pump is external to the chiller. Additionally, the chilled water loop must have a minimum ow bypass at the end of the loop (by others) to maintain minimum ow through the chiller.

The valves on a Multistack chiller are dual purpose. First, a user dened number of valves can be programed to remain open at all times as a minimum ow bypass through the chiller. This is selectable at the master controller or through the BAS with an optional web-portal. Second, the motorized valves modulate to maintain leaving chilled water temperature control out of each heat exchanger. The bypass valve(s) will follow the lead compressor and remain locked in a bypass position and rotate with the lead compressor. Remaining valves will open when corresponding compressors start. The compressor will then modulate for leaving water temperature control. Valves close when corresponding compressors shut o. When there is no demand for cooling all valves are closed with only the pre-selected number of bypass valves remaining open for a minimum ow chiller bypass.

If all evaporators and condensers are equipped with variable ow valves the master controller, in conjunction with each corresponding slave controller, will modulate the valves for simultaneous leaving chilled water and condenser head pressure control from each heat exchanger (with the exception of the heat exchanger(s) programmed as the minimum ow chiller bypass).

Page 34

Factory Setup/Commissioning

Go to the System Variables Menu and select Factory Settings to access the program type and other setup information. Setup is to be done by the Multistack authorized startup technician. Setup parameters are factory set to default values. Jobsite conditions must be congured at startup. To change these settings requires a password that is available to authorized service technicians by calling Multistack at (608-366-2400).

The Standard Program should be used on applications where no glycol is used in the chilled water side. In this mode the chilled water temperature cutout is set at 34°F.

The Low Temperature Program should only be used in applications that have a minimum of 25 percent glycol in the chilled water loop. Cutout on low water temperature in this mode is 20°F and the suction temperature cutout setting (with R-410A refrigerant) is set at 15°F.

Condenser Water Set-Point: If power-actuated buttery valves are used on the condenser side, this value should be set for the desired discharge pressure. Depending on the condenser water inlet temperature this will adjust the valve to maintain the desired pressure.

Variable Flow: Select ENABLE if doing variable ow on the chilled or condenser side. If not, select DISABLE. To do variable ow, water control valves must be installed on each module between the water header pipe and heat exchanger.

Bypass: Select ENABLE to leave the valve on the lead module open for minimum ow bypass. Select CHILLED WATER or CONDENSER WATER bypass. If no valves are installed on the module keep this variable in the DISABLE MODE.

For information on basic control setup of the modules see the Multistack Comput 600 User manual.

Pressure Readings

The operating suction and discharge pressures in the system are directly related to water ow, condenser temperature, chilled water set-point, and system cleanliness. Standard operating conditions with 95°F leaving condenser water and 45°F leaving chilled water temperature are discharge pressure at 325 psig ( 102°F saturated) and suction pressure at 114 psig (38°F saturated).

All water-cooled modules have a high pressure (HP) cutout safety device and a backup HP cutout switch. The HP cutout is 475 psig for a standard watercooled module with R-410A. Each module also includes a low pressure (LP) safety cutout. The LP cutout is set in the module program at 50 psig.

If circuits are experiencing HP faults rst check to see that the cooling tower fan is operating. Next, verify proper water ow to the brazed plate heat exchanger and conrm the strainer and lters are clean and free owing.

A LP fault is an indication of low refrigerant charge in the system. If a circuit trips out on a LP fault check the static pressure of the system while the circuit is in the o mode. If pressures are low, check the circuit for possible leaks. The circuit can be pressurized to 15 psig with refrigerant and topped to 160 psig with dry Nitrogen.

Maintenance

Use proper safety equiment, tools and procedures when operating and servicing this equipment. Be sure to review all safety warnings, cautions and notes found on Pg. 3 of this manual.

Preventive Maintenance

Multistack publication MAINT-002-0416 provides heat exchanger preventative maintenance guidelines. Contact your Multistack representative for more information. Multistack water cooled chillers, especially those with brazed plate heat exchangers, require careful control of the chilled and condensing water circuits to prevent heat exchanger fouling. Refer to Multistack publication MAINT-001-0416 for water sample collection information.

Page 35

Strainer Cleaning, Heat Exchanger Cleaning

All Multistack modules have a 30-mesh lter strainer in the condenser and evaporator inlet headers. The purpose of the strainer is to prevent debris from entering the heat exchanger. An external “Y” or basket type system strainer should also be installed as a pre-lter to the Multistack strainers. There is no pre-determined time for cleaning the strainer cartridges. The frequency of this process is dependant on the water quality in the condenser and/or evaporator loop. Normally, debris in a water loop is takes the path of least resistance and accumulates in the last modules to receive water.

Multistack modules include the Multiush automatic blow down system installed on the condenser side of the last module in the chiller array. The Multiush system is controlled by a timer in the Master Control and opens once a day to remove debris from the loop. Multiush does not eliminate the

need to pull and clean the strainers, but reduces the frequency.

The eect of debris buildup in the condenser water inlet lter cartridge will create nuisance HP (high pressure) faults. By checking the pressure dierential between the inlet and outlet of the condensers, it can be determined if the strainers are contaminated. Refer to the MS 010-085X Product Data Catalog for correct pressure drop of your model. For an MS070X module with a 10° F Delta T, the condenser side pressure drop should be 17’ / 7.4 psi; for chilled water 16’ / 7 psi. To keep HP faults from repeating, the strainers will need to be pulled and cleaned. If HP faults still occur after cleaning the strainer cartridges the condenser pump should be checked for proper ow. If ow is not a problem the heat exchangers may need to be cleaned. Refer to Multistack Heat Exchanger Cleaning Bulletin (MAINT-003-0416). Use this procedure to remove and clean the lter cartridges on the condenser side.

1. Turn o the chiller, shut down the condenser pump, and close the buttery/gate valves to the condenser.

2. Drain the water remaining in the condensers and header pipes by opening the drain valve in the pipe stubs or by removing the end grooved tting cap on the Multiush system.

3. Remove the rst lter in the Multiush and remove all remaining lters in the bottom condenser header pipes.

4. Slowly open the top buttery / gate valve, allowing water to ow through the condensers and onto the oor for approximately 30 seconds. This will push out any debris trapped in the bottom of the heat exchanger as the lters are removed.

5. Clean the lters with a hose, power washer, or wire brush as needed and re-install. Slide lters in until contacting the lter stop ring on the rst module. Keep an extra set of strainers for quick re-installation. These lters are available for purchase through Multistack representatives.

6. Close the system by installing any grooved tting clamps previously removed.

7. Open the ¼-inch petcock bleed valves on the pipe stubs.

8. Fill the system by opening the bottom buttery/gate valve and lling from the bottom up. Close the ¼-inch petcock valves and open the top buttery/gate valve after air has been bled from the system.

9. Start the condenser pump. Bleed any remaining air in the system once the pump has started and start the chiller.

If circuits trip out on Low Suction Temperature, or Low Chilled Water Temperature, check the chilled water inlet lter cartridge. The strainers are located in the top header on the chilled water side. The previous instructions on condenser strainer removal do not need to be exactly followed. If the strainers are clean the fault may be caused by a low ow condition or a low set point in the Master Control. If these possibilities are eliminated the evaporator heat exchangers may need cleaning.

Compressor Oil Level

All compressors on water-cooled modules have an oil level sight glass on each compressor. Each module is run tested and the oil level is set at the factory. R-410A scroll compressors are single stage and oil level is set at ⁄ – ¼ full sight glass. The compressor uses POE oil. Use Copeland type 998-E022 or Nu Calgon 32-3MA. Call Multistack service at (608)366-2400 for factory oil charge for each compressor.

Refrigerant Charge / Evacuation

All water-cooled modules are factory charged to recommended refrigerant volumes. Prior to charging, each circuit is evacuated to 150 microns and held 15 minutes. The proper refrigerant charge for each module can be found on the module data plate. For proper charge on water-cooled modules, the circuit should be charged until the sight glass clears.

Model Refrigerant Lbs. Per Circuit Oil Charge Per Circuit (in Pints)*

MS010X 8 3.5 MS015X 8 6.9 MS020X 8 6.9 MS030X 12 6.9 MS040X 15 9.5 MS050X 18 9.5 MS070X 24 13.3 MS085X 28 13.3 * Based on Copeland compressors

Page 36

Filter Driers

Multistack modules contain very short piping runs to the major components. Only a micro refrigerant charge (0.6 lbs. per ton) is used, and all circuits are evacuated to 150 microns. For this reason a liquid line lter drier is not factory installed in the unit. When changing a major component in the system, a replaceable core suction line lter kit can be added to reduce contamination. The suction lter kit can be purchased from Multistack through your local

representative.

Superheat/Subcooling

Subcooling is necessary in the system to prevent ash gas as the refrigerant enters the expansion valve. Multistack uses a mechanical-type expansion valve on all modules. Clockwise adjustment of the valve increases superheat. On water-cooled modules, superheat is set at 10°-12°F during the factory run test. Multistack condensers are sized so that liquid refrigerant subcooling occurs without a separate subcooler. The general range of subcooling is 10°-20°F.

Daily Log Sheet

Log sheets foud at the back of this manual can be used daily, weekly or as desired to record operation characteristics of the chiller. The information recorded on the log sheet can also help diagnose potential system problems.

Annual Maintenance

Annual maintenance requirements for Multistack Chillers involve proper shut-down of the machine and cleaning of the heat exchangers. The Preventative Maintenance bulletin (MAINT-002-0416) and Heat Exchanger Cleaning bulletin (MAINT-003-0416) describe the recommended procedures for both processes. Multistack makes available the 151A Cleaning Kit to assist with this process. Refer to the 151A Cleaning Kit bulletin for more details.

Also check annually:

• All electrical components (contactors, fuses, relays, etc.) to identify any signs of excessive wear. Check for tight connections.

• Superheat, pressure gauges, oil levels, Master Controller condition, and sensor accuracy should also be checked.

• Exercise all isolation valves, manual or power operated.

Compressors

In the event of a compressor failure, determine the cause. A motor burn due to a fault in the motor insulation is quite rare. Most burnouts are actually caused by a mechanical condition or lubrication problem. In the event of a burnout, proper clean up procedures should be followed.

1. Check all electrical components of the circuit (contactors, fuses, wires, etc.)

2. If necessary do a system clean up. Nu-Calgon RX-11 ush, or Sporlan System Cleaner work well.

3. Install a suction lter drier with burnout core.

4. Evacuate the system to a minimum of 500 microns and hold for 20 minutes.

5. Charge the circuit with virgin refrigerant. Charge with liquid into the discharge side. See proper refrigerant charge on nameplate data of unit.

6. Run the system 2-3 weeks with burnout lter core. Replace with standard core drier

Heat Exchanger Cleaning

Multistack publication MAINT-003-0416 provides procedures for cleaning heat exchangers. Contact your Multistack representative for more information.

Page 37

Troubleshooting

Multistack modular chillers use the Carel PCO3 master control. A user manual for the PCO3 controller is supplied with the submittal package. The user manual details the dierent status screens and explanations of system or module faults. Use the following guide to troubleshoot modules and the PC03 controller.

Fault Solution Fault Solution

• Turn chiller on

• Check sensors

• Check load limit setting in system variables

• Check VSP setting is system variables

• Check entering CHW sensor location

• Look for system problem (low water Volume, low load)

• Check strainers in condenser headers

• Check condenser water ow

• Check refrigerant charge / leaks

• Check expansion valve

• Check suction sensor

• Check set-points in system variables

• Check for ow restriction

• Check settings in system variables

• Check cables at J11 comm ports

• Check dip switch settings

• Check components in control circuit

• Check wire crimps in control circuit

• Check ratio of HP to LP

• Check cables at J11 comm ports

• Check for possible power issues

No Display on Master Module

EX 1,2, Interlock

EX 4 Interlock

Waiting For Chilled Water Flow

Waiting For Condenser Water Flow

Low Chilled Water Temp

No Demand

100% Demand all the time

• Check main disconnect for power

• Check circuit breakers in module

• Check transformer in modules

• Check for 24V at J1 on board

• Check appropriate interlock component

• Check jumpers on TB11 in master control

• Check for proper rotation, phasing

• Check PPM device

• Check CHW pump

• Check ow switch operation

• Check lter strainers

• Check TB11 inputs #3 - #7

• Check CW pump

• Check ow switch operation

• Check lter strainers

• Check TB11 inputs #3 - #8

• Check LCHW sensor

• Check set-points in system variables

• Check for ow restriction

• Check entering CHW sensor

• Check set-points in system variables

• Check sensor location

• Check entering CHW sensor

• Check set-points in system variables

100% Demand, chiller won’t load

Excessive Cycling

High Discharge Pressure (HP)

Low Suction Pressure (LP)

Low Suction Temperature

Communication Error

Circuit Fault

P Lan Error

Page 38

lllMULTISTACK Chiller Daily Log Sheet

Job Name:

Job Number:

Module Serial Numbers:

Date:

Status Suct. Press Head Press Suct. Temp LoChw Temp Fault (if any)

Comp #1

Comp #2

Comp #3

Comp #4

Comp #5

Comp #6

Comp #7

Comp #8

Comp #9

Comp #10

Comp # 11

Comp #12

Ent. Chw Lvg. Chw Ent CW Lvg. CW Demand Capacity

System

Upset Loset VSP Load Limit Tdi Index

System

Comments:

CHW P Drop CW P Drop

Page 39

lllMULTISTACK Chiller Daily Log Sheet

Job Name:

Job Number:

Module Serial Numbers:

Date:

Status Suct. Press Head Press Suct. Temp LoChw Temp Fault (if any)

Comp #1

Comp #2

Comp #3

Comp #4

Comp #5

Comp #6

Comp #7

Comp #8

Comp #9

Comp #10

Comp # 11

Comp #12

Ent. Chw Lvg. Chw Ent CW Lvg. CW Demand Capacity

System

Upset Loset VSP Load Limit Tdi Index

System

Comments:

CHW P Drop CW P Drop

Page 40

1065 Maple Avenue P.O. Box 510 Sparta, WI 54656

Phone 608-366-2400 • info@multistack.com

www.multistack.com

MS-IOM-001 0317

Supersedes MS-IOM-001 0117

FWB

Multistack MS010XC, MS015XC, MS020XC, MS050XC, MS040XC Maintance Manual

Specifications and Main Features

Frequently Asked Questions

User Manual