Carel pCO2 Series Application Program

Standard air-conditioning units
Carel Cod. +030221421 – Rel. 1.2 – April, 11, 2003
26
9.2 OTHER TEMPERATURE FUNCTIONS
The high and low temperature alarms cause alarm screen signalling and have modifiable delay time.
The dehumidification stop differential establishes the minimum temperature below which dehumidification is interrupted. Dehumidification can
start again if temperature returns above the value established by the humidification start offset; differential and offset are modifiable.
9.3 CLOSE CONTROL UNITS WITH TWO WATER COILS
These close control units are equipped with a warm water coil and a cold water coil. In addition, heating can also be executed by heaters. The
following diagram shows the cooling devices action, whereas the heating devices action is dealt with in the paragraph describing the direct
expansion units.
9.4 CLOSE CONTROL UNITS WITH SINGLE WATER COIL
In these close control units, the coil provides for both heating and cooling, depending on the type of water circulating inside it. In practice, the
unit works as it was equipped with two different coils. The coil operation depends from a Summer / Winter digital contact that “reports”
whether the circulating water is warm or cold to the board; if the “type of water” circulating inside the coil complies with the ambient request,
the valve is modulated to regulate temperature.
In addition, heating can also be executed by heaters or a warm coil. For any information about coil and heaters operation, refer to the previous
paragraphs.
Ambient
tem
p
.
(
°C
)
COOLING
HEATING
0%
100%
100%
0%
Cold proportional band
Warm proportional band
Temperature set
19.5 22.5 23.0 23.5 26.5
23.0 23.5 26.5
0-10Volt COLD WATER VALVE
100%
0%
100%
0%
THREE-POSITION COLD WATER
Three-
p
osition valve runnin
g
time
3°C 0.5°C 0.5°C 3°C
Opening start point (0%)
Opening end point
(100%)
23.0 23.5 26.5
Ambient
tem
p
.
(
°C
)
Ambient
tem
p
.
(
°C
)
13.0 18.0 20.0 22.0 23.0 26.0 33.0
Ambient
tem
p
.
(
°C
)
COOL.
HEA
Temperature set
Warm band Cold band
Low tem
p
erature alarm Hi
g
h tem
p
erature alarm
3°C 3°C
Dehumid. stop different.
5
°
C
4
°
C
Dehumid. start offset
10°C 10°C
ON OFF
Dehumidification stop

Carel pCO2 Series Specifications

General

Brand	Carel
Model	pCO2 Series
Category	Controller
Language	English