background image

10

Refrigerant Piping Connections

 IMPORTANT

The compressor in the unit this air handler is matched 

with  contains  PVE  oil  (Polyvinyl  ether).  PVE  oil  is 

formulated  for  hydrofluorocarbon  (HFC)  refrigerants, 

such as R410A, which this system contains. While it may 

have some miscibility properties with mineral-based oil 

and POE oil (Polyolester), it is not recommended to mix 

PVE oil with any other type of refrigerant oil.

Refrigerant leaks are unlikely; however, if a refrigerant 

leak  occurs,  open  a  door  or  windows  to  dilute  the 

refrigerant in the room. Turn off the unit and all other 

appliances that may cause a spark. Call a licensed 

professional HVAC technician (or equivalent) to repair 

the leak. 

Use only R410A refrigerant to charge this system. Use 

of  other refrigerant or gas will damage the equipment.

Do not allow air or other contaminants to enter system 

during installation of refrigerant piping. Contaminants 

will result in lower system capacity and abnormally high 

operating pressures and may result in system  failure or 

explosion.

Insulate all refrigerant piping.

Refrigerant pipes may be very hot during unit operation. 

Do not allow contact between wiring and bare copper 

pipes. 

After refrigerant piping connections have been 

completed,  check  the  system  for  leaks  per  

commissioning instructions.

 WARNING

 IMPORTANT

Support  ALL  piping  within  12  in.  (305  mm)  of  any 

mechanical fitting such as a flared connection.

 WARNING

Danger  of  fire.  Bleeding  the  refrigerant 

charge from only the high side may result 

in pressurization of the low side shell and 

suction tubing. Application of a brazing torch 

to a pressurized system may result in ignition 

of the refrigerant and oil mixture. Check the 

high and low pressures before applying heat.

 CAUTION

Brazing  alloys  and  flux  contain  materials  which  are 

hazardous to your health.
Avoid breathing vapors or fumes from brazing operations. 

Perform operations only in well-ventilated areas.
Wear gloves and protective goggles or face shield to 

protect against burns.
Wash hands with soap and water after handling brazing 

alloys and flux.

 IMPORTANT

Refrigerant  lines  must  be  clean,  dry,  refrigerant-grade 

copper lines. Air handler coils should be installed 

only  with  specified  line  sizes  for  approved  system 

combinations.

Handle  refrigerant  lines  gently  during  the  installation 

process. Sharp bends or kinks in teh lines will cause 

restrictions.

 IMPORTANT

Only use brazing rods/sticks which are suitable/

recommended for air conditioning pipework installations 

- Do Not Use Soft Solder.

 CAUTION

Purge low pressure nitrogen [1 to 2 psig (6.0 to 12.8 

kPA)] through the refrigerant piping during brazing. This 

will help to prevent oxidation and the introduction of 

moisture into a system.

To prevent the build-up of high levels of nitrogen when 

purging be sure it is done in a well ventilated area.

Summary of Contents for VRF VMDB Series

Page 1: ...sed professional HVAC installer service agency or the gas supplier Failure to follow safety warnings and these instruc tions exactly could result in property damage dan gerous operation serious injury...

Page 2: ...ce a fuse with a fuse of a different rating Do not use a jumper wire to replace a fuse Do not insert your hands tools or any other item into the air intake or air outlet at either the indoor or outdoo...

Page 3: ...UNIT REAR OF UNIT SECTION A A SECTION D D SECTION B B SECTION C C SECTION B B SECTION C C SECTION A A SECTION D D TOP OF UNIT NOTE Unit orientation reversed to show alternative filter location and re...

Page 4: ...2 13 1 25 1 3 4 44 1 7 8 48 CONDENSATE LIFT PUMP Size A B C D E F G H J in mm in mm in mm in mm in mm in mm in mm in mm in mm 012 36 1 4 921 10 5 8 270 25 3 8 645 22 1 2 572 39 3 4 1010 2 5 8 67 28 71...

Page 5: ...in any form Minimum clearances must be observed at all times NOTE Horizontal installation only 20 508 mm Minimum Service Clearance 24 610 mm Air Flow 24 610 mm Minimum Service Clearance TOP VIEW DUCT...

Page 6: ...te support for the weight of the duct system Duct system must not be supported by the indoor unit It is recommended that you use flexible joints canvas at the point where the duct connects to the unit...

Page 7: ...d then a nut onto each rod below each suspension bracket Use the leveling nut beneath suspension bracket to adjust the unit to the correct height Remove the electrical tape holding the upper washers a...

Page 8: ...es the filter retaining bracket and slide the bracket away from the unit 3 Grasp the filter removal tab and slide the filter out Figure 7 Loosen Filter Retaining Bracket Filter removal tab Figure 8 Sl...

Page 9: ...pplied foam insulating tape to the return air opening on the bottom of the unit See Figure 11 Figure 11 Apply Foam Insulating Tape Field supplied foam insulating tape 5 Use the existing screws to re i...

Page 10: ...PORTANT Support ALL piping within 12 in 305 mm of any mechanical fitting such as a flared connection WARNING Danger of fire Bleeding the refrigerant charge from only the high side may result in pressu...

Page 11: ...on conditions 4 All refrigerant piping shall be free of defects debris and oil 5 Connect the liquid and gas lines to the evaporator coil 6 Always use an appropriate heat absorption compound to protect...

Page 12: ...rnal drain pump Suspension Rods Drain line Structural Ceiling 3 ft 1 m Support straps NOTE Drain line should be sloped 1 4 inch per foot 18 mm per m AWAY from unit and should be supported as needed to...

Page 13: ...system in the cooling mode If the internal pump is being used ensure that the pump is operating and the water in the pan is draining freely If the internal pump is not being used pour the water into t...

Page 14: ...ions Clamp cables securely and make sure that connections are tight to avoid strain on wiring Insecure wiring connections may result in equipment failure and risk of fire Wiring must be installed so t...

Page 15: ...gure 21 Typical Power Wiring Diagram VRF Heat Recovery System Shown L2 L3 L1 L2 L1 208 230V 3Ph 60Hz or 460V 3Ph 60Hz Power supply 208 230V 1Ph 60Hz Power supply Mode Selection Box Indoor unit Indoor...

Page 16: ...PQ PQ H1 H2 H1 H2 H1 H2 Outdoor Unit Communication Terminal Block P Q H1 H2 X Y O A K1 K2 MS Box Communication Terminal Block P Q Indoor Unit Communication Terminal Block HA HB 12V COM P Q Ground drai...

Page 17: ...ler Signal transmission wire X2M 0 58 0 72 Terminal base of power supply X1M 0 87 1 06 Grounding terminal M4 1 06 1 43 PQ PQ Outdoor unit mainunit Outdoor unit sub1unit Outdoor unit sub2 unit Install...

Page 18: ...E F8 No address Outdoor unit fault Water level alarm Emergency stop Remote OFF E6 DC fan motor error E7 EEPROM failure error 5V GND 12V ONLY USED FOR TESTING CN30 RED BLACK HA HB 12V COM Q P Magnet Ri...

Page 19: ...6 Locate the return air thermistor to the conditioned area of which the indoor unit serves Figure 29 Sensor Thermistor Relocate the unit return air sensing from inside the unit to a location within th...

Page 20: ...K WHITE RED XS4 XS3 XS2 XS1 XS6 XP7 XS7 CN12 NOTE 1 Refer to manual for communication wiring 2 Please use the 2 conductor shielded twisted cable for communication NOTE Component in dash line is option...

Page 21: ...l indoor temperature T1 6 The middle coil temperature T2 7 The coil inlet temperature T2A 8 The coil outlet temperature T2B 9 The actual superheat temperature 10 The actual subcool temperature 11 Erro...

Page 22: ...it Fault EE High Water Alarm A0 Emergency stop D8 Remote off U4 MS self inspection error F8 MS error Table 8 Fault Code Display on Controller Error Code Description F0 Communication Address error betw...

Page 23: ...23...

Page 24: ...m Reference and adhere to the latest revision of the installation instructions Installation instructions can be downloaded from www lennoxvrf com www lennoxcommercial com www lennoxpros com and the Le...

Reviews: