daiken splits difference between f3 alarm and e4

[craigmouring]

Hi guys I am new to this forum so please dont be too harsh my background has been mostly chillers so pretty new to air con I was at a site today 4 splits 3 showing code f3 and 1 showing e4 further inspection the e4 unit short of gas but the others high discharge temp could this be down to shortage of gas or possibly one of the fans is not rejecting latent heat

Thanks

[AbsoluteWDJ]

Hi guys I am new to this forum so please dont be too harsh my background has been mostly chillers so pretty new to air con I was at a site today 4 splits 3 showing code f3 and 1 showing e4 further inspection the e4 unit short of gas but the others high discharge temp could this be down to shortage of gas or possibly one of the fans is not rejecting latent heat

Thanks

Operate each system with gauges on. Sounds to me like a shortage of gas on all of them!

[install monkey]

check indoor filters and outlets havent been blanked off

[Darrenp]

F3 ... that the discharge pipe temperature has increased greatly above normal operation levels.
This can be caused by a fault with the compressor if the oil return to it is poor it could start to run to hot or possibly even a shortage of refrigerant not cooling the compressor effectively.

This could be either R3T, R3-1T, R3-2T, or R3-3T depending on the VRV model installed.
Could also be a dodgy comp , had that before on an f3 fault , Also thermistors

[Darrenp]

E4 This is stating that there has been a low pressure error on the system.
This could have been caused by a blockage in the pipe work or a possible shortage of refrigerant. It could also be due to a fault with the low pressure sensor/switch

[Brian_UK]

Also with the E4 fault, if it is an old system with long pipe lengths you can sometimes have a slow suction pressure build up and the PCB times out the LP bypass before the pressure has risen.

Could also be a faulty pressure switch.

I have problems with some old kit in these slightly cooler mornings when the LP trips due, I think, to the PCB getting worn, old and bloody minded. The condenser fans are still on full chat during the start-up phase which keeps the pressures low and the LP times out, hence an E4.

With the F3 check the pipe temperature with the unit running.

[VRVIII]

Do you know the unit model numbers?

Where the units operating in heating or cooling mode when the errors occured?