EVCO c-pro nano CHIL - Manual (Page 100)

C-PRO NANO CHIL AND C-PRO MICRO CHIL – APPLICATION MANUAL
Pag. 100
WARNING – Operating mode change-over can also happen while the machine is ON: in this case,
the machine switches itself OFF – complying with all its timings – then commutates, and thereafter
switches itself back ON automatically.
Note: During commutation, high and low-temperature controls are enabled.
Note: Commutation is disabled during defrosting cycles.
6.4.1 Heat-pump-only mode
If the machine has been configured as chiller + heat pump, by setting parameter PG08 = 1 it is
possible to choose to make it operate as a heat pump only. This configuration forces the MOdE
parameter to the value 1 (hEAt), and can exclude from normal operation the use of outlet
temperature and anti-frost probes, together with their associated alarms:
- To disable the outlet temperature probes, alarm and connected consequences, set parameter
PH22=0.
- To disable anti-frost, alarm and connected consequences, set parameter Pr01=0.
Note: The PG08 parameter can only be modified while the machine is in OFF mode.
6.4.2 Geothermal heat pumps
So-called “geothermal” heat pumps are peculiar water-to-water units, which exchange heat with the
subsoil, via a buried piping system in which a water-glycol solution circulates.
An alternative to the simple winter heat pump is that of exploiting the “low” temperature of the
subsoil for summer chilling, when combined with a system of floor-mounted or other type of
radiating panels: given the vast heat-exchange surface, a thermal jump of only few degrees is
sufficient to produce summer chilling. In this case, it is necessary to provide between the
geothermal circuit and user loads the activation of a by-pass element, which can be a pump or
motor-operated valve.