EVCO EPK4BHQ1AH Installer manual - Manual (Page 92)

EVCO S.p.A. c-pro 3 NODE kilo AHU | Application manual ver. 1.0
page 92 of 114
6.19 Unit with single heating-cooling coil (seasonal)
In this type of unit (PG01=1) there is only one dedicated valve for heating and cooling and, if enabled, there is a
single circulation pump; the operating mode (parameter MOdE) determines which behaviour to utilize.
In the same way all the controls (fans, free-cooling/free-heating, controls of set-point, alarms, etc..) are distinguished
based on the operating mode. The heating function is guaranteed when the parameter MOdE=1; meanwhile the
cooling function is guaranteed when MOdE=0.
The correct software configuration is obtained considering all the resources (parameters and operating states)
normally utilized for heating the machine when using more than one coil, which, in these particular centres, are
considered mixed resources commanded univocally based on operating mode (summer/winter). The “mixed”
hardware parameters to consider for the unit at single coil with circulation pump are the following:
PG01=1 (single coil)
PG10: enable circulation pump (heating)
For units using a single coil it is not possible to manage dehumidification and post-heating. The resources
normally managed for cooling and post-heating are not piloted; it is therefore recommended to reset all the
configuration parameters in order to avoid malfunctions.
6.19.1 Right coil steps status
In the right coil steps status it is possible to control the relative configuration.
6.19.2 Primary control
For these types of units it makes sense to also set the primary control parameter PG04; using the appropriate
configuration parameter, PG04, it is possible to choose the organ on which the primary control will be made from the
central unit: fans or valves.
- If PG04 = 0, the primary control is made on the fans which, at the appropriate time, will be controlled in
different ways (parameter PF01). This type of configuration excludes utilization of the valve and therefore the
controller does not provide any commands on the analogue/digital outputs for controlling the single
heating/cooling valve.
- If PG04=1, the primary control is made on the valve. The intake of hot/cold air is modulated by the
heating/cooling coil; meanwhile the fans are working to recirculate the air of the central unit. Fan control
can be set with the appropriate parameter PF01.
In units with more than one coil the parameter PG04 does not condition any control.