54
Marvair Wall Mount Heat Pump I&O Manual
06/2023 Rev.7
E.
Check Incoming Power at Terminal Block and verify Proper Voltage and Balance BEFORE
STARTING UNIT.
❒
208/230V 1 Phase 60 Hz.
❒
208/230V 3 Phase 60 Hz.
❒
460V 3 Phase 60 Hz.
❒
380V 3 Phase 50Hz.
❒
575 3 Phase 60 Hz.
❒
Other____________
Single Phase Units
Measured Line to Line Volts L1&L2 = _______V.
Is incoming voltage between Min and Max voltage listed on unit Data Label? ..............
❒
Yes
❒
No
An incoming voltage that is Not between the Minimum and Maximum listed on the unit Data Label
Must be addressed and corrected before placing the unit into full time operation. Improper voltage
can cause the compressor to overheat and cause premature failure.
Three Phase Units
Measured Line to Line Volts L1&L2 _______V., L1&L3 ________V., L2&L3 ______V.
Is incoming voltage between Min and Max voltage listed on unit Data Label? ..............
❒
Yes
❒
No
An incoming voltage that is Not between the Minimum and Maximum listed on the unit Data Label
Must be addressed and corrected before placing the unit into full time operation. Improper voltage
can cause the compressor to overheat and cause premature failure.
Measured Line to Line Balance
Is incoming voltage properly balanced? (use formula below to calculate balance) .........
❒
Yes
❒
No
Average Voltage =
(L1&L2 + L1&L3 + L2&L3)/3 = _______________V.
Deviation Difference = Average Voltage - Maximum Deviation = ______________V.
Voltage Imbalance = (Deviation Difference x 100)/ Average Voltage = ___________%
A Voltage Imbalance greater than 2% with the unit running must be addressed and corrected. Excess
Line to Line Voltage Imbalance can cause the compressor to overheat and cause premature failure.
Example:
Voltage Imbalance = (Average Voltage – Maximum Deviation) x 100
Average Voltage
Measured Voltages:
L1 & L2 = 241 Volts
L1 & L3 = 243 Volts
L2 & L3 = 235 Volts
719 / 3 = 239.7 Volts (Average Voltage)
239.7 (Average Voltage) – 235 (Maximum Deviation) = 4.7 (Deviation Difference)
(4.7 x 100)/239.7 = 1.95% Voltage Imbalance (
Less than 2% is acceptable
)
