Preparing The Unit For Operation - Trane Voyager CV Installation And Maintenance Manual

Table 28. Condenser fan/compressor sequence
Compressor Staging
Sequence
Unit
Size
(Ton) Step 1 Step2 Step 3
CPR 1*
27.5 -
30
CPR 1, 2
CPR 1*
35
CPR 1, 2
CPR 1 **
40 CPR 2***
CPR 1, 2
CPR 1 **
CPR 2,
50
3****
CPR 1, 2,
3
Notes:
1. The Compressor(s) listed under each step are the operating
compressors. On 27.5 to 35 Ton units with Lead/Lag, CPR1 will
alternate but the fan sequence will remain the same. On 40 & 50
Ton units with Lead/Lag, the compressor(s) in step 2 & 3 will
alternate and the fan sequence listed for that step will be in
operation.
2. Conventional thermostat sequence: Y1=CPR1, Y2=CPR2 (40 CPR 2
& 50 CPR 2,3), Y1 + Y2 = CPR1,2 (40 CPR 1,2 & 50 CPR 1,2,3)
3. During active dehumidification all compressors will be staged "On". 
For units equipped with four condenser fans (40 and 50 Ton), the
condenser fan output states will be controlled based on the O/A
temperature. If O/A is above 85°F, all condenser fan outputs will be
energized. If O/A falls below 80°F, Output B will de-energize and will
not re-energize again until the O/A rises above 85°F. 
For units configured with three condenser fans (27.5 to 35 Ton), a
maximum of two condenser fans will energize. Output A will
energize above 85°F and de-energize when the O/A falls below
80°F; Output B will remain de-energized during active
dehumidification. If O/A falls below 80°F, Output A will de-energize
and will not re-energize again until O/A rises above 85°F
* Single circuit, manifolded compressors pair.
** First Stage, Number one refrigeration circuit, Standalone compressor is
"On".
*** First Stage is "Off", Number two refrigeration circuit, standalone compres-
sor is "On"
****First stage is "Off", Number two refrigeration circuit, manifolded com-
pressor pair is "On" operating simultaneously
RT-SVX34F-EN
O/A
Condenser Fan Temp.
Output (°F)
Output Output Fans
A B "Off"
Fan #2
Fan #3
N/A
Fan #2 -10
Fan #3
Fan #2
Fan #3
Fan #2 -20
N/A
Fan #3
Fan #2
Fan #3, 4
Fan #2
Fan #3, 4
Fan #2 -30
Fan #3, 4
Fan #2
Fan #3, 4
Fan #2 -10
Fan #3, 4
Fan #2 -30
Fan #3, 4
Figure 46. Condenser fan location
70
90
60
65
85
55
50

Preparing the Unit for Operation

70
20
Be sure to complete all of the procedures described in this
60 section before starting the unit for the first time.
Use the checklist provided below in conjunction with the
"Installation Checklist" to ensure that the unit is properly
50
installed and ready for operation.
20
60
Hazardous Voltage!
55
Disconnect all electric power, including remote
disconnects before servicing. Follow proper lockout/
50
tagout procedures to ensure the power can not be
inadvertently energized. Failure to disconnect power
before servicing could result in death or serious injury.
• Check all electrical connections for tightness and
"point of termination" accuracy.
• Verify that the condenser airflow will be unobstructed.
• Check the compressor crankcase oil level. Oil should
be visible in the compressor oil sight glass. The oil
level may be above the sight glass prior to the initial
start. Use appropriate lighting (flashlight) to verify the
presence of oil.
• Prior to unit startup allow the crankcase heater to
operate a minimum of 8 hours to remove liquid
refrigerant from the compressor sump.
• Optional Service Valves - Verify that the discharge
service valve, suction service valve, and liquid line
service valve is fully open on each circuit.
• Check the supply fan belts for proper tension and the
fan bearings for sufficient lubrication. If the belts
require adjustment, or if the bearings need lubricating,
refer to the Maintenance section of this manual for
instructions.
• Inspect the interior of the unit for tools and debris and
install all panels in preparation for starting the unit.
Startup
WARNING
53