Airedale Easicool Cabinet

[Daz man]

I have a technical issue regarding an Easicool close control cabinet (DF17X-EZR) serial number - 81806788-001. On refrigerant R410a.

Roughly installed 2009/2010.


The digital controller interface on the front of the cabinet is showing an 'Airflow fail fault'


This flags up after roughly about one minute after first initiation.


I have proved the air pressure switch and the internal fan speed controller to find both fully operational. I know this as there is an identical cabinet on site and I have swapped the two mentioned parts.


The two white wires 502 and I can't remember the second, i think it is 515, that enter the air proving switch I have connected together to prove operation. This does solve the issue with the unit now failing to alarm and in sequence bringing in both cooling and humidification, working as it should.


Both positive and negative tubes (blue & yellow) off the air proving switch have been checked for obstruction, water etc to find clear.


The one thing I did notice when the air proving switch was 'shorted out' which seems odd, was that the internal fan (direct drive, no belts) is motoring but seems very slow! Obviously I wouldn't like to put my hand in there as its not that slow, but normally you can hear the draft under the false floor when the fans are running - this seems half the speed.


The indoor fan motor % run settings have also not been altered in the menu of the controller.
Maximum is @ 100%
Minimum is @ 25%


Is it possible to have a fan motor down? If so Is there a way I can prove this by carrying out checks on the motor, windings etc?


The capacitor also checked out ok.

help/advice required!

[install monkey]

increase minimum fan speed to 70% see if that cures the airflow issues

[Daz man]

Will do, top man cheers for that! Do you reckon that will work? As far as I'm aware the settings haven't been changed and its been ok for the last couple of years?

[install monkey]

if theres a parameter on the software for fan speeds, only reason for this is for once at setpoint fans slow down or for dehumidifing. you mentioned that the fan pressure switch was linked- hence working ok before

[al]

Are the filters clean, if three phase is it running correct direction?

al

[NoNickName]

My 0.02: you've got a loose wire in the terminal box or the differential pressure switch was set/reset to a high trip value.

[Daz man]

Right! Problem solved! It was quite simple - Install Monkey, I thank you.

on the Airedale digital controller which I think is a Carel controller same on the Denco's

find the sub setting MANUFACTURER - then USER - scroll through until you find main fan speed setpoint.

for what ever reason this was set @ 50%!

I changed this to 70% like the other three cabinets on site - unit fixed no further alarms.

there is another setting in the controller which kind of contradicts this as I mentioned in my post - minimum still set at 25% with maximum at 100%

will post in a min which setting this is under!!

[Daz man]

Referring to the above-

press PRG button then under MANUFACTURER (enter password) then PARAMETERS. you will then find a section 'Main fan speed' setpoint limits: on these cabinets I've got Maximum 100% Minimum 20%

thats what was confusing me

[install monkey]

Controlled by the microprocessor the de-humidification feature reduces fan
speeds by 20% (adjustable). The reduction of fan speed increases de-humidification
which means that time the taken to reduce the room humidity to the required level is
drastically decreased, along with the energy required to do so.
DE-HUMIDIFICATION
Sizes 6 - 26
(with Electric Heating and
Humidification only)
The return temperature is monitored during de-humidification to ensure that the
temperature does not fall to a critical level. If the temperature reaches the low limit dehumidification
is cancelled until the return air temperature increases.

[Daz man]

Cheers fella, much appreciated