Daikin unit behaving oddly.

[CraigF]

Evening all,

A couple of my engineers are on a site with a Daikin RZQ71B9V3B1 mated with a FCQ71DAV3B cassette on R410a.

The unit pulls down to 7 bar low side then cuts the compressor but no fault codes?? Im gonna head to site tomorrow myself and have a look. They have reclaimed, vacced and regassed to no avail.....Anyone had anything similar?? Cheers in advance!

Craig

[bigspee]

Hi I have had a fair few of these calls, and the last one I went too I had a break through! It sounds the same as the fault i had ( cant remember model numbers ) but it turned out that the system is cycling on the freeze protection sensor on the evap coil. If the coil reaches below a certain temp (about -5) for a certain amount of time the compressor stops running until the coil gets back upto temp! The unit I was working on was short of gas by about 150 grams. Check the coil temps from the BRC controller.
Is it in a comms room as well?

[The Viking]

Hmm, what else is happening in this system?

All the sensors reading correct temperatures?
Humidity level above 30% in the room?
Any drop in suction line temperature between the service valve and the compressor?

[CraigF]

As for what else is happening, I do not know... Seems strange to have no fault code.

Its not in a comms room situ, its in a Petrol Filling Station Shop (starts with tes, and ends in co ). I'm sure once i've had a good recce tomorrow ill have some more info...

Thanks tho!!!

[frank]

With lots of the error codes flagged up on Daikin systems, they only occur after numerous attempts by the system to restart and try again. If the fault continues, say for 6 times in a certain time period, only then does the error code appear.

Patience and an understanding of the control logic always helps in these situations

[bigspee]

its in a Petrol Filling Station Shop (starts with tes, and ends in co ).
Thanks tho!!!

No problem - every little helps! ;-)

[bigspee]

How did you get on? Get to the bottom of it?