Danfoss MCX08M User Manual

DKRCC.PS.RI.A1.02 / 520H4358 - Air Handling Seq. user manual - V 2.2
Produced by Danfoss Electronics spa Graphic Department, 10-2009
42
Danfoss Electronics spa
Air Handling seq. - user manual
9| Frost protection
To enable the frost protection function you have rst to dene with FP1 the probe used for controlling the
temperature.
FROST PROTECTION
FRO Frost Min Max Default U.M. Text value
FPP Frost Protection
FP1 Probe selection 1 3 OUt ;NO;OUT;tC2
FP2 Alarm setpoint 5,0 90,0 2,0 °C
FP3 Proportional band 0,1 20,0 1,0 K
Tab 29_ [Frost protection - Frost protection]
When the selected probe temperature is close to the alarm setpoint FP2, the heat actuators are activated
proportionally as described in the following gure.
Fig 34_ [Frost protection - Frost Protection]
When the temperature goes below the alarm setpoint FP2, then the “A07 - Freeze Alarm” is generated and heat
power is set to 100%, cool power to 0%, the external damper goes to its minimum position and the heat recovery
is OFF.
Note
* The “A07 - Freeze Alarm” is
generated also by the thermostat
(digital input) “AAI - Freeze Alarm”.
(See “14.3] Alarms table”).
* If the “A07 - Freeze Alarm” is set
by Congurator to be active even
when the unit is OFF, then all the
actions on the heating actuators
described above are active even
when the unit is OFF
9.1| Frost Prevention in OFF
FROST PREVENTION IN OFF
FRO Frost Min Max Default U.M. Text value
FPR Frost Prevention
FP4 Setpoint OFF 5,0 90,0 2,0 °C
FP5 Proportional band 0,1 20,0 1,0 K
FP6 Integral time 0 9999 0
Tab 30_ [Frost protection - Frost prevention in OFF]
When the unit is OFF, the controllers works to maintain the “tC2 – Antifreeze” probe, if present, to the value set with
the setpoint OFF FP4 with PI logic.
This function acts on both the heat sequences but the heat recovery and the external damper remain closed.

Danfoss MCX08M Specifications

General

Brand	Danfoss
Model	MCX08M
Category	Controller
Language	English