LU-VE F31HC Series, Инструкции по установке, эксплуатации, обслуживанию и техническому обслуживанию

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REFRIGERANT PIPING — CONTINUED
All F31HC and F35HC model series unit coolers are equipped with a venturi-flo refrigerant distributor
which ensures maximum efficiency of the coil under most all operating conditions. There is no orifice
or nozzle plate to select / install in the distributor inlet. For optimum coil performance the TXV should
be mounted within the end compartment of the unit and as short a distance as possible from the dis-
tributor inlet.
Do not install any elbows between the outlet of the TXV and the inlet of the distributor!
A 1/4” O.D. equalizer tube is supplied on all units. Never cap this line - use only externally equalized
valves. See
Figures 4, 5 & 6 (below) for location and mounting of the TXV sensing bulb.
If not supplied with the unit, the expansion valve must be selected according to the design characteris-
tics of the particular system - taking into consideration the following criteria;
Refrigerant type, design
room temperature, system TD or design saturated suction temperature (SST), liquid temperature
(subcooling) and the minimum operating head pressure (SCT) of the system.
LU-VE can provide a
separate valve selection table of suggested expansion valves for the most common refrigerants, oper-
ating temperatures and system TD’s however we strongly recommend that you consult with your sup-
plier or valve manufacturer for selection assistance - especially for any unusual or non-standard appli-
cations.
If a liquid line solenoid valve is to be installed in the system we recommend placing it in the field piping reasonably close to the unit
cooler. Do not select valves based only on the physical connection size - the valve you install may be much to large for the application
which can result in operational problems with the valve and possibly even damage to the connected unit cooler or system piping. Re-
fer to the valve manufacturers capacity charts or selection software or consult with your local valve supplier for assistance. Always be
sure to provide adequate pipe clamps and supports for external piping and components - never allow the unit coil connections to sup-
port the weight or unrestricted movement of any field installed piping components. Any damage to the coil which is determined to be
caused by improper field piping design / installation will void the product warranty coverage.
Do not bend or forcibly move the suction
header connection or liquid distributor
assembly of the coil in order to line up
with the field installed piping. Adjust all
field piping to the unit connections!
NO
YES
NO
YES
Always direct the torch flame
away from all unit and valve
connections when brazing to
avoid overheating and
potentially damaging
components. Use wet rags or
thermal paste when necessary
and always flow low pressure
nitrogen while brazing to
prevent scale / oxidation from
forming inside the system.
NO
YES
Mount the TXV sensing bulb on a straight, horizontal section of the suction line tubing (Figure 4) as close to
the evaporator outlet as possible and before the suction line P-trap (Figure 5). Position the bulb on the
side of the pipe at one of the locations noted (Figure 6). Securely fasten the bulb to the side of the pipe
with the provided straps. Completely wrap the bulb and piping with insulation to complete the installation.
Figure 5
NO
YES
Figure 6 Figure 4
7/8” OD Pipe and Smaller
7/8” OD Pipe and Larger