Ground-Loop Applications; Installation Of Supply And Return Hose - Carrier PTV Installation, Start-Up And Service Instructions Manual

Water Flow
Control Regulator
Valve (field-installed
(field-installed accessory)
accessory)
Pressure
Tank
Water Out
Water In
Pump
Boiler
Drains
(field-installed)
Shut-Off
Valve (field-installed accessory)
Strainer (field-installed accessory)
(16 to 20 mesh recommended for
filter sediment)
Fig. 13 -- Typical Ground-Water Piping Installation
Water Supply and Quantity -- Check water supply. Water
supply should be plentiful and of good quality. See Table 2 for
water quality guidelines.
IMPORTANT: Failure to comply with the above required
water quality and quantity limitations and the closed-
system application design requirements may cause damage
to the tube-in-tube heat exchanger. This damage is not the
responsibility of the manufacturer.
In all applications, the quality of the water circulated
through the heat exchanger must fall within the ranges listed in
the Water Quality Guidelines table. Consult a local water treat-
ment firm, independent testing facility, or local water authority
for specific recolranendations to maintain water quality within
the published lhnits.
GROUND-LOOP APPLICATIONS -- Temperatures between
25 and 110 F and a cooling capacity of 2.25 to 3 gpm of flow
per ton is recolranended. In addition to complying with any
applicable codes, consider the following for system piping:
• Limit piping materials to only polyethylene fusion in the
buried sections of the loop.
• Do not use galvanized or steel fittings at any time due to
corrosion.
• Avoid all plastic to metal threaded fittings due to the poten-
tial to leak. Use a flange fitted substitute.
• Do not overtighten connections.
• Route piping to avoid service access areas to unit.
• Use pressure-temperature (P/T) plugs to measure flow of
pressure drop.
INSTALLATION OF SUPPLY AND RETURN HOSE
KIT -- Follow these piping guidelines.
1. Install a dram valve at the base of each supply and return
riser to facilitate system flushing.
2. Install shutof_balancing valves and unions at each unit to
permit unit removal for servicing.
3. Place strainers at the inlet of each system circulating
pump.
4. Select the proper hose length to allow slack between con-
nection points. Hoses may vary in length by +2% to -4%
under pressure.
5.
Refer to Table 3. Do not exceed the minhnum bend radius
for the hose selected. Exceeding the minhnum bend radi-
us may cause the hose to collapse, which reduces water
flow rate. Install an angle adapter to avoid sharp bends
in the hose when the radius falls below the required
minimum.
NOTE: Piping must comply with all applicable codes.
Insulation is not required on loop water piping except where
the piping runs through unheated areas or outside the building
or when the loop water temperature is below the minimum ex-
pected dew point of the pipe ambient. Insulation is required if
loop water temperature drops below the dew point.
Do not bend or kink supply lines or hoses.
Pipe joint compound is not necessary when Teflon threaded
tape is pre-applied to hose assemblies or when flared-end
connections are used. If pipe joint compound is preferred, use
compound only m small amounts on the male pipe threads of
the fitting adapters. Prevent sealant from reaching the flared
surfaces of the
:joint.
NOTE: When anti-freeze is used m the loop, assure that it is
compatible with Teflon tape or pipe joint compound employed.
Maximum allowable torque for brass fittings is 30 ft-Ib. Ifa
torque wrench is not available, tighten finger-tight plus one
quarter turn. Tighten steel fittings as necessary.
Optional pressure-rated hose assemblies designed specifi-
cally for use with Carrier units are available. Similar hoses can
be obtained from alternate suppliers. Supply and return hoses
are fitted with swivel-joint fittings at one end to prevent kink-
ing during installation.
Backup wrench is required when tightening water connec-
tions to prevent water line damage.
Refer to Fig. 14 for an illustration of a supply/return hose
kit. Male adapters secure hose assemblies to the unit and risers.
Install hose assemblies properly and check them regularly to
avoid system failure and reduced service life.
11