icing up problem

[cool zab]

We have four fujitsu AUY25UNAKL out door units all are which are icing up. Not defrosting thay are all on a corner of a building on the floor.

There are another 10 of these units on the same site . Which do not have this problem.

We have check the refrigerant charges. replaced the condensor probes.

These units are connected to cassettes AUY25UUAR

This problem is present while the outside ambient is low. Which affects the indoor temps.

Please could anyone help

Thanks Cool zab

[S_Line]

This depends on many other factors.
THe area the units are expected to heat, the temp setting you are trying to achieve in the area.
The Insulation of the area. We recieve many calls over this problem, its normally with buildings that have poor insulation, and with customers who only wanted the units for cooling and now expect them to heat like a tropical island resort lol !

You need to look at defrost times as well, some makes defrost quicker than others, some dont defrost at all !( cheap junk)

[DC5-T]

check the temp settings