Thermal Care NQ Series, Руководство по установке и эксплуатации

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Pump LED
The Pump LED is solid green while in normal running
operation. It will flash red if the overload safety trips.
Hot Gas Bypass LED
The Hot Gas Bypass LED will pulse or light solidly
when the chiller is operating at partial load. Under
partial load, the hot gas bypass valve opens in order
for the chiller to maintain a constant To Process
temperature. The hot gas bypass valve opens to a
variable percentage. The LED indicates an
approximate opening percentage by pulsing for
varying amounts of time. If the LED lights for 5
seconds, the valve is open 50%, if it lights for 10
seconds the valve is open 100%. The longer that this
LED stays on, the more unused excess capacity is
available from the chiller. If the Partial Load LED
stays off, the chiller is under full load by the heat
from the process. If the Partial Load LED stays on,
the chiller has a very small load on it from the
process. If this low load condition persists, the To
Process temperature may begin to drop below the
Set Point temperature, eventually cycling off
compressor(s).
Compressor #1 LED
The Compressor #1 LED is solid green while
Compressor #1 is running. It will flash red if a
compressor overload condition exists (only chillers
with the following nominal tonnages: 15, 25, 30, 35,
and 40). Compressor #1 will be enabled whenever
the temperature of water leaving the chiller rises
above the Set Point by an amount equal to the
control parameter PS1 (Compressor #1 Positive
Spread). PS1 is equal to 2 °F by default. The
compressor will be disabled if the temperature of
water leaving the chiller drops below the Set Point
by an amount equal to the control parameter nS1
(Compressor #1 Negative Spread). The parameter
nS1 is set to 4 °F by default. See the Program Menu
section for instructions on how to adjust PS1 and
nS1. To prevent excessive compressor cycling, the
control board has a compressor anti-cycle delay
timer built in. Any time a compressor is prevented
from turning on by the anti-cycle timer, the
Compressor Recycle LED will be lit.
Compressor #2 LED
The Compressor #2 LED is solid green while
Compressor #2 is running. Compressor #2 is only
present on chillers 20 tons and larger. It will flash red
if a compressor overload condition exists (only
chillers with the following nominal tonnages: 15, 25,
30, 35, and 40). Compressor #2 will be enabled
whenever the temperature of water leaving the
chiller rises above the Set Point by an amount equal
to the control parameter PS2 (Compressor #2
Positive Spread). PS2 is equal to 3 °F by default. The
compressor will be disabled if the temperature of
water leaving the chiller drops below the Set Point
by an amount equal to the control parameter nS2
(Compressor #2 Negative Spread). The parameter
nS2 is set to 5 °F by default. See the Program Menu
section for instructions on how to adjust PS2 and
nS2. To prevent excessive compressor cycling, the
control board has a compressor anti-cycle delay
timer built in. Any time a compressor is prevented
from turning on by the anti-cycle timer, the
Compressor Recycle LED will be lit.
Temperature Limit LED
The Temperature Limit LED will flash yellow if a
deviation warning exists. It will flash red if a high or
low critical temperature safety alarm condition exists.
Electrical Phase Error LED
The Electrical Phase Error LED flashes red when a line
voltage problem exists. This error indicates a loss of
phase, phase reversal, or phase imbalance.
Low Flow LED
The No Flow LED will light if the flow through the
chiller is below the preset acceptable level. When the
Start button is depressed, this safety is defeated for
a period of 5 seconds in order for the pump to
establish flow. This safety will shut off the pump and
the compressor. If the chiller is shut down by the No
Flow safety, the Start button must be depressed in
order to restart the pump and reset the time delay.