background image

Issue 1324

507120-01

Page 12 of 18

Airflow - Cooling Blower Speed 

The cooling blower speed is factory configured to provide 

correct airflow for an outdoor unit that matches the maximum 

cooling capacity rating of the air handler. 

If the outdoor unit is smaller than the maximum cooling 

capacity rating for the air handler, the cooling blower speed  

may need to be changed.  Refer to blower performance 

chart, Table 2. 

1.  Disconnect all power supplies. 

2.  Remove the air handler access panel. 

3.  Locate pin number 2 on the blower relay.  Two black 

wires are connected to this terminal pin.  One connects 

to pin number 5 on the blower relay, one connects to an 

in-line splice connecting to a red wire. 

4.  Remove the wire going to the 4-pin blower motor 

connector from the splice. 

5.  Connect the blower lead [Red (La), Black (HI)] onto the 

splice from the 4-pin blower motor connector. 

NOTE:

 

 

Reuse the factory-installed plastic cap on whichever 

wire is not used. 

6. 

Replace all panels. 

7.  Reconnect power. 

CHANGE BLOWER SPEED 

NOTE: 

 

Refer to wiring diagram located on the unit access 

panel and blower performance (Table 2). 

 

All air data measured external to unit with 1 inch non-

pleated air filter in place. 

  All factory settings are medium speed except the -48 

which is set to low speed from the factory. 

  All data given while air handler is operating with a dry 

DX coil. 

Blower Performance (3-Speed PSC) -240V (CFM @ ESP. -in. w.c.)

• 

Blower Performance (CFM vs. ESP inches H2O)

• 

Cooling speeds should not be reduced below factory setting.

• 

Units with electric heat approved at 0.5” maximum and medium blower speed minimum.

• 

Downflow units should be set to high speed minimum.

• 

Different speeds can be set for heating mode.

ELECTRIC SHOCK HAZARD!

 

Disconnect all power supplies before 

servicing. 

Replace all parts and panels before 

operating. 

Failure to do so can result in death or 

electrical shock. 

  

WARNING

Summary of Contents for BCE3M 18

Page 1: ...Condensate Drain 7 Duct Systems and Filters 8 Connecting Refrigerant Lines 9 Sealing the Unit 9 Electrical Connections 10 Airflow Cooling Blower Speed 12 Check Out Procedures 13 Operation13 Maintenan...

Page 2: ...9 12 1 4 311 18 7 8 479 5 3 4 146 16 7 8 429 17 3 4 451 17 432 19 7 8 505 20 3 4 527 19 3 8 492 5 1 2 140 43 1092 18 1 2 470 22 559 6 152 16 406 5 1 2 140 13 1 2 343 17 3 4 451 17 432 16 1 2 419 20 3...

Page 3: ...space routing requirements for refrigerant line condensate disposal filters duct system wiring and accessibility for service Refer to the air handler rating plate on the air handler for specific infor...

Page 4: ...s are provided for electrical wiring entrance For ease in installation it is best to make any necessary coil configuration changes before setting air handler in place For all performance testing units...

Page 5: ...ntal configuration is shown in Figure 3 5 If the unit is suspended the entire length of the cabinet must be supported If you use a chain or strap use a piece of angle iron or sheet metal attached to t...

Page 6: ...ugged Remove the plugs from the front drain pan ports 5 Re install modified coil drain pan assembly in air handler in the same orientation as before Figures 6 and 7 Figure 6 Install Main Drain Pan Mou...

Page 7: ...ure 9 On units of this type where the blower draws rather than blows air through the coil traps must be installed in the condensate drain lines primary and auxiliary if used Traps prevent the blower f...

Page 8: ...he drain pan to allow complete drainage of the pan NOTE Horizontal runs must have an anti siphon air vent standpipe installed ahead of the horizontal run See Figure 9 An extremely long horizontal run...

Page 9: ...oid damaging the rubber grommets in the cabinet while brazing slide the rubber grommets over the refrigerant lines until they are away from the heat source 5 Braze using an alloy of silver or copper a...

Page 10: ...t all power supplies 2 Remove the air handler access panel 3 Route the field supply wires to the air handler electrical connection box 4 Use UL listed wire nuts to connect the field supply conductors...

Page 11: ...Page 11 of 18 Issue 1324 507120 01 Figure 12 Low Voltage Connections 3 Speed PSC Motor...

Page 12: ...rom the 4 pin blower motor connector NOTE Reuse the factory installed plastic cap on whichever wire is not used 6 Replace all panels 7 Reconnect power CHANGE BLOWER SPEED NOTE Refer to wiring diagram...

Page 13: ...elay coil and then the indoor blower relay energizes The normally open contacts close causing the indoor blower motor to operate The circuit between R and Y is completed closing the circuit to the con...

Page 14: ...emperature of the cabinet The temperature humidity difference between the inside and outside of the cabinet can cause condensation on the inside or outside of the cabinet which leads to sheet metal co...

Page 15: ...Page 15 of 18 Issue 1324 507120 01 Start Up and Performance Checklist Horizontal Configuration Figure 14...

Page 16: ...Issue 1324 507120 01 Page 16 of 18 Figure 15 Start Up and Performance Checklist Upflow Configuration...

Page 17: ...rnish the following information a complete model and serial number b proof of required periodic maintenance installation date and location and c an accurate description of the problem WARRANTY LIMITAT...

Page 18: ...odification change or alteration of the unit except as expressly directed in writing by Allied Air 4 Improper use accident neglect or unreasonable use or operation of the unit including operation of e...

Reviews: