Specifications

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Troubleshooting
The in and outs of R-410A
R-410A is a non-ozone depleting blend of two refrigerants
-HFC-125andHFC-32inaftypercentmixture.R-410A
exhibits higher operating pressure and refrigeration capacity
than R-22. R-410A is intended for use in new air conditioning
applications that have traditionally been used HCFC-22 (R-
22). Due to higher capacity and pressure of R-410A, it must
not be used in existing R-22 systems.
AlthoughR-410Aisnon-ammableatambienttemperature
and atmospheric 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 nitrogen and
R-410A can be used for leak testing.
Lubrication
R-410A should be used only with polyester (POE) oil. The
HFC refrigerant components in R-410A will not be compat-
ible with mineral oil or alkylbenzene lubricants. R-410A sys-
tems will be charged with the OEM recommended 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 normally charged into
a system, a valve should be installed in the charging line to
ashtheliquidtovaporwhilecharging.
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
– do not put R-410A in a 300 PSIG rated cylinder.
Recycle/recovery equipment must be designated for R-410A.
R-410A pressure is greater than R-22. Improper equipment can
cause severe injury or death.
WARNING
Note: Because a water source heat pump operates under a
wide range of water and air temperatures, the values
printed below are to be taken as suggested pressure
and temperatures.) All Daikin McQuay water source
heat pumps are designed for commercial use. The
units are designed for the cooling mode of operation
and fail safe to cooling. The reversing valve is
energized for the heating mode of operation.
Superheat Head Pressure Water Delta T
8 to 14 degrees 335-355 PSIG 10° to 14°
Note: All information above is based on ISO standard
13256-1 and tested at these conditions.
General Maintenance
1. Normal maintenance on all units is generally limited
tolterchanges.Unitsareprovidedwithpermanently
lubricated motors and require no oiling even though oil
caps may be provided.
2. Filter changes are required at regular intervals. The time
period between changes will depend upon the project
requirements. Some applications such as motels produce
a lot of lint from carpeting and linen changes, and will
requiremorefrequentlterchanges.Checkltersat60-
dayintervalsfortherstyearuntilexperienceisacquired.
Iflightcannotbeseenthroughthelterwhenheldupto
sunlight or a bright light, it should be changed. A more
critical standard may be desirable.
3. The condensate drain pan should be checked annually and
cleanedandushedasrequired.
4. Record performance measurements of volts, amps, and
water temperature differences (both heating and cooling).
A comparison of logged data with start-up and other
annual data is useful as an indicator of general equipment
condition.
5. Periodic lockouts almost always are caused by air or
water problems. The lockout (shutdown) of the unit is
a normal protective result. Check for dirt in the water
system,waterowrates,watertemperatures,airowrates
(maybeadirtylter),andairtemperatures.Ifthelockout
occurs in the morning following a return from night
setback, entering air below machine limits may be the
cause.