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3.6 - Supply and return piping installation
IMPORTANT:
Right-hand units - entering water is upper pipe.
Left -hand units - entering water is lower pipe.
CAUTION: To ensure proper functioning of unit and system,
be sure to connect entering water to upper pipe on right-hand
units. On left-hand units, connect entering water to lower
pipe.
3.6.1 - Supply and return hoses
Optional pressure-rated hose assemblies are available for use
with units. Use the following guidelines when installing supply
and return hose assemblies.
1.
Install supply and return hoses fitted with swivel-joint
fittings at one end to prevent the hose from twisting.
2.
Use male adapters to secure the hose assembly to the unit
and the riser.
3.
Do not allow the hose to twist during installation. Twisting
may damage the hose wall or the rubber compound.
4.
Use pipe joint compound sparingly on the fitting adapters’
male pipe threads.
5.
Prevent sealant from reaching the joint’s flared surfaces.
6.
Do not use pipe joint compound when Teflon thread tape
is pre-applied to hose assemblies or when flared-end
connections are used.
7.
Maximum torque that may be applied to brass fittings is
40.8 Nm. When a torque wrench is not used, tighten brass
fittings finger-tight plus one quarter turn.
8.
Tighten steel fittings as necessary.
9.
Shut-off/balancing valves, flow indicators, and drain tees
in the supply runout and return at each floor aid in loop
balancing and servicing.
3.6.2 - Supply and return piping
System piping MUST comply with all applicable codes.
1.
Install a drain valve at the base of each supply and return
riser to enable system flushing at start-up and during
routine servicing.
2.
Install shut-off/balancing valves and unions at each unit to
allow unit removal for servicing.
NOTE: If flex hoses are used, unions are not necessary.
3.
Install strainers at the inlet of each system circulating pump.
NOTE: Since loop temperatures are normally between 15 and
32
°
C, pipe sweating and heat loss do not occur at normal
ambient temperature conditions. Insulation must be installed on
loop water piping on those sections that run through unheated
areas or are located outside the building. If loop temperatures
are expected below the ambient dew point, the optional internal
insulation (extended range) package must be ordered.
CAUTION: DO NOT bend or kink supply lines or hoses.
Damage to unit may result.
4.
Before making the final water connections, flush the system
as described in the Pre-Start-Up section of this manual.
After flushing the system, connect piping and hoses to the
proper supply, return and condensate connections of the unit.
NOTE: When necessary, use adapters to connect hoses.
5.
Install any other system components, as required, following
manufacturer’s instructions.
6.
Reinstall the front cabinet by carefully lowering the front
cabinet over the chassis onto the backplate.
3.7 - Condensate piping installation
Connect the unit condensate drain to the building condensate
drain with a flexible, nonpressure-rated 5/8-in. ID plastic hose.
Avoid kinks in this hose to ensure an unobstructed flow of con-
densate from the unit to the drain.
The horizontal run of the condensate hose is usually too short
to pose any drainage problems, however, the horizontal run of
condensate line should be pitched at least 100 mm for every
500 mm of run (in the direction of flow). Avoid low points and
unpitched piping since dirt collects in these areas and may cause
stoppage and overflow.
Field installation of a trap or vent is not required unless specified
by local codes. The 50KQE units are designed in a blow-through
configuration. The condensate drain pan is located on the outlet
side of the blower so that the pressure in the drain pan is higher
than the atmospheric pressure.
