Mammoth 1/2 to 6 Tons: High Efficiency Single Circuit Horizontal and Vertical (A-Vintage) - Manual (Page 20)

20
MAMM-WSHP-IOM-1MA
Troubleshooting
R-410A
The In’s and Out’s of R-410A
R-410A is a non-ozone depleting blend of two
Refrigerants — HFC-125 and HFC-32 in a fifty percent
mixture. Refrigerant 410A exhibits higher operating
pressure and refrigeration capacity than R-22.
Although R-410A is non-flammable at ambient tem-
perature and atmosphere pressure, it can become
combustible under pressure when mixed with air.
(NOTE: R-410A should not be mixed with air under
pressure for leak testing. Pressure mixtures of dry nitro-
gen and R-410A can be used for leak testing.)
Lubrication
R410A should be used only with polyolester (POE) oil.
The HFC refrigerant components in R-410A will not be
compatible with mineral oil or alkylbenzene lubricants.
R-410A systems will be charged with the OEM recom-
mended lubricant, ready for use with R-410A.
Charging
Due to the zeotropic nature of R-410A, it should be
charged as a liquid. In situations where vapor is nor-
mally charged into a system, a valve should be in-
stalled in the charging line to flash the liquid to vapor
while charging.
All Mammoth A-Vintage units are designed
for commercial use. Units are designed for the
cooling mode of operation and fail safe to heating.
Symptom
Head
Pressure
Suction
Pressure
Compressor
Amp Draw
Super
Heat
Subcooling
Air
Temp
Differential
Water
(Loops)
Temp
Differential
Safety
Lock
Out
Charge
Undercharge
System
(Possible Leak)
Low Low Low High Low Low Low Low Pressure
Overcharge Sys-
tem
Pressure
High High High Normal Low
Normal
Normal High Pressure
Low Air Flow
Heating
High High High
High
Low High Low High Pressure
Low Air Flow
Cooling
Low Low Low
Low
Low Low Low Low Temp
Low Water Flow
Heating Low Low
Low Low High Low High Low Temp
Low Water Flow
Cooling
High High High High Low Low High High Pressure
High Air Flow
Heating
Low Low Low Low High Low Low Low Temp
High Air Flow
Cooling
Low High Normal High Low Low Normal High Pressure
High Water Flow
Heating
Normal Low Low Low Normal Normal Low High Pressure
High Water Flow
Cooling
Low Low Low Low HIgh Normal Low Low Temp
Troubleshooting Refrigeration Circuit
Low
Normal
Normal
Normal Normal
TXV Restricted High Low
Normal
High High Low Low Low
WARNING!
It is very important to make certain that the recycle or
recovery equipment used is designed for R-410A. The
pressure of R-410A refrigerant is approximately 60
percent greater than that of R-22. Pressure gauges
require a range up to 800 PSIG high side and 250
PSIG low side. Recovery cylinders require a 400 PSIG
rating.