Taylor Taylormate 150, Руководство по обслуживанию

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15
Models 150, 152, 162, 168
Controls and Systems
Separate Hopper Refrigeration (SHR)
Function
Maintains mix storage temperature below 41
°
F
(5.0
°
C).
Operation
The compressor circulates refrigerant around the coil
wrapped mix hopper(s). An EPR valve (Evaporator
Pressure Regulator) regulates the refrigerant
pressure in the hopper coil, thereby determining the
refrigerant temperature. A sensing probe monitors the
gas temperature and the system cycles according to
the temperature control setting.
Running Specifications
Refrigerant R12 134A
EPR setting 24-26 PSI 20-21 PSI
Suction pressure at
compressor 12-20 PSI 1-15 PSI
Compressor running
amps approx. .8 amps .8 amps
Compressor lock rotor
amps approx. 2.2 amps 6.5 amps
Overcharge System
A refrigerant overcharge results in inadequate run
times and, consequently, high hopper temperatures
and exaggerated bacteria growth.
When first starting an overcharge compressor system,
operation may seem normal. However, suction
pressures will be higher than necessary, causing
higher amp draw and additional operating heat. The
dome of the compressor will be hotter than normal.
After sufficient running time, the compressor will cycle
off on the temperature control. On subsequent cycles
before the compressor cycles off on the temperature
control, it may terminate by use of the compressor
overload. At this time the short cycles begin. From this
point, each time the compressor is called upon to
operate, the accumulated heat combined with the
additional amp draw from the higher suction pressure
causes the overload to stop operation prematurely. At
this time, the temperature will never be satisfied. This
means the compressor operation will operate by use
of the overload. Under normal conditions, total amp
draw of the compressor and fan is approximately 0.8
amp. Under lock rotor, the amperage will raise.
During an overload condition, there are two
circumstances which may exist. During the “OFF”
mode, pressures may equalize and the overload
switch closes. The system may start, but terminate
shortly when the overload re-opens. The overload may
cool and re-close, but pressures may not have
equalized. The system then will not start, and may
eventually re-open the overload. The only way to
correct the compressor operation would be to switch
off the power and allow the system to cool sufficiently
before re-establishing power.
Another area to consider is the operating voltage and
how it effects overload operation. During a lock rotor
condition, it requires up to 20 minutes to trip the
overload with 208 operating volts. With 240 operating
volts, this time requirement may be as little as 5
minutes.
The following method best describes how to adjust the
refrigerant charge to achieve proper operation from
the system. Fill the hopper(s) half full of mix to achieve
a 40
°
F (4.4
°
C) established hopper temperature. Start
the refrigeration with the EPR valve set to 24
PSI/164.5 kPa (R12) or 20 PSI/138 kPa (134A).
Refrigerant charge should now be adjusted to
establish a 20 PSI/138 kPa (R12) or 15 PSI/103 kPa
(134A), or slightly below. Never adjust refrigerant
charges or EPR pressure with a hopper medium above
40
°
F (4.4
°
C). With a hopper of 40
°
F (4.4
°
C) or below,
suction pressures should never read above 20
PSI/138 kPa (R12) or 15 PSI/103 kPa (134A). As
hopper temperatures lower, the suction pressure will
drop but should never drop below 12 PSI/83 kPa (R12)
or 1 PSI/7 kPa (134A). Remember, if hopper medium
exceeds 40
°
F (4.4
°
C), suction pressure will also rise.
When operating correctly, the compressor dome will
measure room temperature and the suction line will be
cool, but not frosted.
Note: The dryer must be installed vertically, with the
capillary tube at the bottom.