C L I M AT E M A S T E R W AT E R - S O U R C E H E AT P U M P S
C o n s o l e s
R e v. : 5 N o v. , 2 0 0 9 B
16
C l i m a t e M a s t e r W a t e r- S o u r c e H e a t i n g a n d C o o l i n g S y s t e m s
Water-Loop Heat Pump Applications
Commercial Water Loop Applications
Commercial systems typically include a number of
units connected to a common piping system. Any unit
plumbing maintenance work can introduce air into the
piping system; therefore air elimination equipment is
a major portion of the mechanical room plumbing. In
piping systems expected to utilize water temperatures
below 50°F [10°C], 1/2” (13mm) closed cell insulation is
required on all piping surfaces to eliminate condensation
(extended range units required). Metal to plastic
threaded joints should never be used due to their
tendency to leak over time.
Te
fl
on tape thread sealant is recommended to minimize
internal fouling of the heat exchanger. Do not over
tighten connections and route piping so as not to
interfere with service or maintenance access. Hose
kits are available from ClimateMaster in different
con
fi
gurations for connection between the unit and the
piping system. Depending upon selection, hose kits
may include shut off valves, P/T plugs for performance
measurement, high pressure stainless steel braided
hose, “Y” type strainer with blow down valve, and/or “J”
type swivel connection. Balancing valves and an external
low pressure drop solenoid valve for use in variable
speed pumping systems may also be included in the
hose kit.
The piping system should be
fl
ushed to remove dirt,
piping chips, and other foreign material prior to operation
(see “Piping System Cleaning and Flushing Procedures”
in this manual). The
fl
ow rate is usually set between 2.25
and 3.5 gpm per ton [2.9 and 4.5 l/m per kW] of cooling
capacity. ClimateMaster recommends 3 gpm per ton
[3.9 l/m per kW] for most applications of water loop heat
pumps. To insure proper maintenance and servicing,
P/T ports are imperative for temperature and
fl
ow
veri
fi
cation, as well as performance checks.
Water loop heat pump (cooling tower/boiler) systems
typically utilize a common loop, maintained between 60 -
90°F [16 - 32°C]. The use of a closed circuit evaporative
cooling tower with a secondary heat exchanger between
the tower and the water loop is recommended. If an
open type cooling tower is used continuously, chemical
treatment and
fi
ltering will be necessary.
Table 3. Antifreeze Percentages by Volume
Type
Minimum Temperature for Freeze Protection
10°F [-12.2
°C]
15°F
[-9.4
°C]
20°F
[-6.7
°C]
25°F
[-3.9
°C]
Methanol
25%
21%
16%
10%
100% USP food grade Propylene Glycol
38%
30%
22%
15%
Table 2: Antifreeze Percentages by Volume
Low Water Temperature Cutout Setting
CXM or DXM Control
When antifreeze is selected, the FP1 jumper (JW3) should
be clipped to select the low temperature (antifreeze 13°F
[-10.6°C]) set point and avoid nuisance faults (see “Low
Water Temperature Cutout Selection” in this manual). NOTE:
Low water temperature operation requires extended range
