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McQuay IM 672-3

29

Service and Maintenance

Removing Stacked Coils

Note –

Top and bottom stacked coils are held together with steel 
plate and screws on one side and drain trough and 
screws on the other side. Remove the plate and trough 
before removing the coils. The coils cannot be removed 
attached together.

1

Disconnect all piping and remove the brass plugs for the 
vents and drains located in the connections. 

2

Remove all screws and remove the access panel.

3

Remove the bolts holding the coil in place and then lift and 
pull out the coil from the side.

4

Remove the steel plate and the drain trough that hold the 
coils together.

5

Remove the bolts on both ends of the top coil holding it in 
place and then lift and slide the coil out.

6

Remove the bolts on both ends of the bottom coil holding it 
in place and then lift and slide the coil out.

Installing Stacked Coils

1

Slide the bottom coil through the opening in the coil section 
onto the bottom coil rests. 

2

Place the coil up against the coil bulkheads to prevent any 
air bypass around the coil. 

3

Once the coil is in place, bolt the coil to the section.

4

Caulk the mounting surface of the steel plate and install the 
plate on the coils.

5

Caulk the mounting surface of the drain trough and install 
the drain trough on the coils.

6

Caulk the seams between the coil casings and blockoffs

.

7

Connect all piping and install the brass plugs for the vents 
and drains located in the connections. 

8

Install the access panel.

Removing and Installing Staggered Coils

Staggered coils have two banks of coils positioned a few 
inches apart in the direction of airflow. Both coils are secured 
to the unit on the connection and opposite connection end of 
the unit.

1

Disconnect all piping and remove the brass plugs for the 
vents and drains located in the connections.

2

To access bolts holding the coils in place, remove the 
panels on both the connection and opposite connection end 
of the coil section. 

3

Each coil is held in place with bolts located in the corners 
of the coil side plates. Remove the bolts and then lift and 
pull the coil out the side.

4

The bottom coil is fastened to the air block off plate. 
Remove the screws attaching this plate to the coil. 

5

Once the fasteners holding the coil in place are removed, 
pull out the coil from either side of the unit.

6

Install the coils in reverse order of removal.

Summary of Contents for Vision CA Series

Page 1: ...McQuay IM 782 1 1 Installation and Maintenance Manual IM 672 3 Group Applied Air Part Number IM 672 Date June 2005 2005 McQuay International Vision Air Handler Sizes 003 090...

Page 2: ...ctions 10 Multizone Damper Adjustment 10 Multizone Mixing Box and Economizer Damper Torque Requirements 11 Mounting Actuators 11 Face Bypass Damper Torque Requirements 11 Piping and Coils 11 Water Coo...

Page 3: ...of the multi zone units with special care Zone dampers are set and inspected before leaving the factory but should be checked on arrival to the job to verify the bell arm and connecting rod set screws...

Page 4: ...can be removed If necessary the unit can be disassembled Maintain at least 54 of clearance in front of electrical power devices starters VFDs disconnect switches and combination devices Electrical po...

Page 5: ...mbled or as separate shipping sections Rig units that require field assembly of shipping sections into position first Shipping sections are provided with a connection splice joint attached on the leav...

Page 6: ...6 18 1 bolt Once the bolt is in place secure the bracket to the adjoining section with a 1 4 1 drill screw Repeat the same procedure on both corners of the unit See Figure 8 Figure 8 Vertical inverted...

Page 7: ...The optional base rail provided by the factory has 5 8 diameter holes in each corner to run hanger rods through To properly support the unit and maintain unit integrity support each shipping section...

Page 8: ...moving parts or electrical wiring See Figure 15 1 Remove padlock if one is present 2 Insert 1 2 socket into cup and rotate 1 4 turn clockwise as shown in Figure 15 If the cup and handle are on the le...

Page 9: ...ation for securing heavier components self tapping screws are not acceptable Ensure that the location permits the full operation of all access doors and panels and does not interfere with other vital...

Page 10: ...t be done after the unit is assembled Also if the bypass duct is over 90 long the duct does not ship in one piece and must be field assembled The field assembly of the bypass duct to the unit requires...

Page 11: ...of the vertical bypass section 3 After the components in the multizone are fitted together fasten the joining plates to the corners in the unit exterior 4 If a damper was ordered assemble it to the se...

Page 12: ...ld deck closes when the bell arms are 45 from the vertical center The hot deck closes when the bell arms are 45 clockwise from the vertical center b Three deck zone dampers The cold deck closes when t...

Page 13: ...e Face and bypass dampers have a torque requirement of 10 in lbs per square foot of damper face area Piping and Coils When designing and installing piping Follow applicable piping design sizing and in...

Page 14: ...h the coil Do not attempt to lift condensate when using modulating or on off control Traps Size traps in accordance with the manufacturers recommendations Make sure that the required pressure differen...

Page 15: ...ker 1 2 check valve Steam main Return main 12 min Vacuum breaker 1 2 check valve Steam main Return main 12 min Full size of return conn Check Valve Strainer Gate Valve Control valve modulating two pos...

Page 16: ...the opposite drive side of the unit are difficult to access from the drive side of the unit Either remove them before the unit is assembled or remove the panel on the opposite drive side to gain acces...

Page 17: ...s are provided by others When the unit is factory provided with a disconnect switch starter or a variable frequency drive VFD the components are mounted on the outside of the unit cabinet Factory wiri...

Page 18: ...cendie et d lectrocution pouvant causer des dommages mat riels des blessures et m me la mort L alimentation lectrique du moteur du ventilateur de m me que la mise la terre du ch ssis du moteur doivent...

Page 19: ...lationship forward curved type fan wheels Notes 1 To obtain rated air performance dimensional relationship must be held 2 Adjust dimension C by loosening wheel hub setscrews shifting wheel s axially a...

Page 20: ...r in ft lbs kg m 1 4 5 5 76 1 16 10 5 1 45 3 8 19 0 2 63 7 16 29 0 4 01 1 2 42 0 5 81 5 8 92 0 12 72 Overlap Table 7 Unit sizes 003 to 035 Fan operating limits Forward curved housed Dia 9 4 9 7 9 9 10...

Page 21: ...00 AF40 25 AF27 00 AF24 50 AF22 25 AF20 00 AF38 50 AF33 00 AF30 00 500 600 700 800 2000 1000 1500 1500 2000 3000 2500 Torque in lb Table 9 Operating limits plenum fans Fan operating limits Plenum fans...

Page 22: ...t or debris on wheel blades b Loose set screws in wheel hub or bearing to shaft c Wheel distorted from overspeed 2 Bent shaft 3 Drive faulty a Variable pitch sheaves Axial and radial runout of flanges...

Page 23: ...y sized fixed sheave A matching fixed sheave provides longer belt and bearing life and minimizes vibration Initially it is best to have a variable pitched motor sheave for the purpose of air balancing...

Page 24: ...xternal key E and securely tighten setscrews B over key and setscrews C into keyway in fixed half of the sheave 4 Put on belts and adjust belt tension Do not force belts over grooves See Fan Drive Bel...

Page 25: ...e Belt Adjustment on page 25 10 Before starting the drive ensure that all keys are in place and all setscrews and all capscrews are tight Check and retighten all screws and retension belts after appro...

Page 26: ...not open C sheaves more than 9 1 2 turns Do not open 5V sheaves more than 6 turns Do not open 8V sheaves more than 8 turns 6 Tighten BOTH locking screws A in the outer locking ring before operating th...

Page 27: ...o N o t R e m o v e I n n e r L o c k i n g R i n g O u t e r L o c k i n g R i n g S p l i t T a p e r B u s h i n g 3 H o l e s f o r S p a n n e r W r e n c h o r D r i f t Belt span Deflection Bel...

Page 28: ...Filter gauge Table 15 Belt deflection force per Browning specifications Cross section Sheave diameter in Deflection force lbs Smallest sheave diameter range rpm range Cross section A B 5V Cross secti...

Page 29: ...l To remove a side or top panel 1 Remove the flat head fasteners located along the sides of the panel 2 Once all fasteners are removed lift off the panel Removing a Frame Channel Frame channels that r...

Page 30: ...nd configuration of the coil affects how the coil can be removed Single banks of coil are fastened only on the connection side of the unit Stacked and staggered coils are fastened on both ends of the...

Page 31: ...e bolt the coil to the section 4 Caulk the mounting surface of the steel plate and install the plate on the coils 5 Caulk the mounting surface of the drain trough and install the drain trough on the c...

Page 32: ...ges must be prepaid The return of the part does not constitute an order for replacement Therefore a purchase order must be entered through the nearest McQuay representative The order should include pa...

Page 33: ...McQuay IM 672 3 31...

Page 34: ...32 McQuay IM 672 3...

Page 35: ......

Page 36: ...ment its care should be a high priority For training information on all McQuay HVAC products please visit us at www mcquay com and click on Training or call 540 248 0711 and ask for the Training Depar...

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