IM UV-3-202D / Page 3
HOSE ASSEMBLY WITH
PIPING THROUGH FLOOR
All hose fittings are brass or zinc plated steel. Assemblies are
suitable for 250 PSIG working pressure, 40°F to 120°F water
temperature, with a minimum burst pressure of 1000 PSIG.
Careful attention must be paid to each individual unit piping
design. Water source heat pump systems require careful bal-
ancing to insure optimum performance. Check all balancing
valves against system head pressure and flows to insure cor-
rect sizing. Refer to AR product bulletin for limitations on sys-
tem water temperatures and recommended water flow.
Parts Supplied By AAF-HermanNelson
(2) 3⁄4˝ Hose Assembly
(2) Adapter Flare
HOSE ASSEMBLY
In order to avoid damage and premature hose failure, it is
very important to comply with the following instructions.
Hose must be installed per Table 1 with gentle radius bends
to prevent kinks. Do not twist hose, observing that printing
on hose (Lay-Line) is not twisted. Be sure all hose bends meet
minimum inside bend radius. See Table 1. Do not overtighten
hose. See Table 1.
WATER SYSTEM CLEANING
The system water piping must be thoroughly cleaned and
flushed in order to remove dirt, chips or other foreign matter
before connecting to the heat pumps or starting the system.
Since the initial condition of the system water may be such
that dirt or other foreign matter may clog or otherwise dam-
age balancing and shutoff valves, it is recommended that
these valves be omitted during the cleaning of the water sys-
tem as outlined in the following procedure.
The entire system should be filled with clean, fresh water
and properly vented. Piping leaks should be repaired as early
in this procedure as they are discovered. With valves posi-
tioned to bypass the heat pumps, heat rejector and the
supplementary water heater, the pump should be started to
circulate water through the system. Check strainers frequently
and clean as often as needed. If the water is extremely dirty
or murky, it is sometimes helpful to continuously flush, using
the system pump, until the water being flushed out of the
pipe loop has become clear. To flush in this manner requires
care to be certain that make-up water is being added fast
enough to replace what is being flushed out. This can be
accomplished by opening the make-up water bypass valve
around the automatic pressure reducer valve, adjusting the
manual valve so that the pump suction pressure gauge con-
tinues to indicate the same positive pressure that existed
before the manual drain and make-up valves were opened.
Continue for at least two (2) hours.
To complete the cleaning, fill the system with fresh water,
adding a cleaning agent such as trisodium phosphate (TSP).
Bypass valves at the heat rejector and supplementary water
heater should be adjusted for normal operation. Disconnect
all power to the heat rejector and heat pump so that they will
not operate while the system is being cleaned. The cleaning
solution should then be circulated throughout the system,
with water heater controls temporarily adjusted to raise the
solution temperature to about 105°F to 110°F. DO NOT allow
the temperature to rise above 110°F, especially in systems
using plastic pipe. Alternate operation of the primary and
standby pumps, and circulate the warm solution for several
hours. Then turn off the water heater and pump, completely
drain the system and refill with fresh water. Repeat the clean-
ing process only if there is indication of foreign matter still in
the system, or if a test of the water indicates that it is even
slightly acid.
The water should be slightly alkaline, with a pH no higher
than 8.0 and no lower than 7.0, which is neutral. Traces of
TSP or similar cleaning agent will tend to leave the water in a
slightly alkaline condition provided all acid forming substances
such as pipe coatings or flux have been properly cleaned
out. A tight system requiring little or no make-up water, with
neutral or slightly alkalline water, will remain in proper oper-
ating condition indefinitely. The addition of chromates or other
corrosion inhibitors is NOT recommended, except when eth-
ylene glycol is added for freeze protection. IN ALL CASES, A
WATER QUALITY EXPERT SHOULD BE RETAINED TO
MAKE A WATER ANALYSIS.
Figure 5. Hose Assembly With Piping Through Floor
Table 1.
HOSE MIN. AFTER HAND TORQUE
I.D. INSIDE ENGAGEMENT, ENGAGEMENT
BEND TIGHTEN NO (FEMALE)
RADIUS MORETHAN STEEL
3⁄4˝6˝ 3
1⁄2˝ 945 In-Lbs.
21" LONG
SYSTEM
WATER INLET
SWIVEL FLARE
FITTING ON HOSE (TYP.)
ADAPTER FLARE
TO M.P.T. (TYP.)
SYSTEM
WATER OUTLET
BALANCING/SHUTOFF
VALVES
(BY OTHERS)
1˝ MAX.
1˝ MAX.
