Comfort-Aire HKV300A - Manual (Page 13)

Installation, Operation & Maintenance HKV SERIES Heat Controller, LLC
12
Water-Loop Heat Pump Applications
Commercial systems typically include a number of units
plumbed to a common piping system. Any unit plumbing mainte-
nance 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 insula-
tion is required on all piping surfaces to eliminate condensation.
Metal to plastic threaded joints should never be employed due
to their tendency to leak over time. All non-distributor class units
include a low temperature-soldered bracket-supported FPT
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to minimize internal fouling of the heat exchanger. Do not
overtighten connections and route piping so as not to interfere
with service or maintenance access. Hose kits are available
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in Figure 5 for connection between the HKV Series and the pip-
ing system. The hose kits include shut off valves, P/T plugs for
performance measurement, high pressure stainless steel braid
hose, "Y" type strainer with blowdown valve, and "J" type swivel
connection. Balancing valves to facilitate the balancing of the
system, and an external low pressure drop solenoid valve for
use in variable speed pumping systems, may also be included
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dirt, piping chips, and other foreign material prior to operation. See Piping System Cleaning and Flushing Procedures. The
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l/m and 4.5 l/m per kW] of cooling capacity. Heat Controller,
Inc., recommends 2.5 gpm per ton [3.2 l/m per kW] for most ap-
plications of water loop heat pumps. To insure proper mainte-
nance and servicing, P/T ports are imperative for temperature
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Cooling Tower/Boiler Systems typically utilize a common loop
maintained 60-90°F [16-32°C]. The use of a closed circuit
evaporative cooling tower with a secondary heat exchanger be-
tween the tower and the water loop is recommended. If an open
type cooling tower is used continuously, chemical treatment and
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Low Water Temperature Cutout Setting CXM Control:
When an antifreeze is selected, the FP1 jumper (JW3) should
be clipped to select the low temperature (Antifreeze 13°F
[-10.6°C]) setpoint to avoid nuisance faults. See Low Water
Temperature Cutout Selection. NOTE THAT THE EXTENDED
RANGE OPTION SHOULD BE SELECTED WHEN LOOP
CONDITIONS ARE EXPECTED TO DROP BELOW 60°F
[16°C].
Figure 5: Typical Water Loop Application
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