Daikin VRVII Problem

[fridgeyman]

hey i have a

REYQ12M8W1B master unit
REYQ12M8W1B slave unit

operating 14 indoors, when in heating mode the master unit runs with both compressors running full tilt and coil frosting nicely and majority of the indoors get nice and warm but some lack heat?? then i cannot get the slave unit to run at all?? and sometimes it will try and run and then flash up L5 fault on the remote, plus it has alot of defrosts when i wouldnt say the spider was over frosted?? not to clued up on daikin really!! just wondered if anyone had come across this or could shine any light
cheers!!

[VRVIII]

hey i have a

REYQ12M8W1B master unit
REYQ12M8W1B slave unit

operating 14 indoors, when in heating mode the master unit runs with both compressors running full tilt and coil frosting nicely and majority of the indoors get nice and warm but some lack heat?? then i cannot get the slave unit to run at all?? and sometimes it will try and run and then flash up L5 fault on the remote, plus it has alot of defrosts when i wouldnt say the spider was over frosted?? not to clued up on daikin really!! just wondered if anyone had come across this or could shine any light
cheers!!

Hi,

An L5 error is due to an over current of inverter compressor at start up.

Probably due to,
1/ Compressor mechanically seized
2/ Compressor down to earth / open circuit
3/ Inverter pcb faulty

[cool#9]

Hi,

An L5 error is due to an over current of inverter compressor at start up.

Probably due to,
1/ Compressor mechanically seized
2/ Compressor down to earth / open circuit
3/ Inverter pcb faulty
Well, am i in the wrong way ?
As far as i know L9 appears due to over current at startup...! ( usually over 15 amps per phase )
I've already seen L5 while there's no current at startup, like an open coil inside the compressor...
I sometimes get L8 due to an open phase while the compressor is running (that was a poor connection between the PCB terminal trip and the compressor's wire).
Or maybe in France we have a special edition of VRVs !!!
rgds
cool#9

[VRVIII]

Hi Cool#9,

I’m not sure what you are getting at or trying to say here



cool#9;174569]Well, am i in the wrong way ?
As far as i know L9 appears due to over current at startup...! ( usually over 15 amps per phase )

L9 error trip condition for VRVII is: Inverter compressor current >16.5 for 5 sec results in inverter standby (retry) if this occurs 3 times in 30 minutes unit will tip on L9



I've already seen L5 while there's no current at startup, like an open coil inside the compressor...

L5 error trip condition for VRVII is: 1/ Instantaneous over current, I think this is about 30amp. 2/ If there is no feed back signal (digitally controlled) to inverter pcb. Obviously if the compressor is disconnected or O/C it will trip on L5!



I sometimes get L8 due to an open phase while the compressor is running (that was a poor connection between the PCB terminal trip and the compressor's wire).

L8 error trip condition for VRVII is: Inverter compressor current >16.5 for 5 sec results in inverter standby (retry) if this occurs 3 times in 60 minutes unit will tip on L8



Or maybe in France we have a special edition of VRVs !!!
rgds
cool#9

No I think it's the special edition engineers in France :rolleyes: :D

[ktm]

Hey u sure system not short of gas? Slave won't ramp up if it can't keep the back pressure up. But yea defo sounds like u have either an inverter comp or board gone down or both.

[martinw58]

sounds like the system is short of gas if you run in cooling do all the units give good cooling

[dakesojo]

try switching off half the indoor units and see how it preforms in heating,if good heating suggest SOG,weight out charge if SOG more than likely caused compresser to fail

[sahersaher644]

how i can calculate duct extenal static pressure

[Crash Pilot]

I would also recommend checking your Inv Compressor and power transistor module on the Inv PCB.

[weidit]

Hey u sure system not short of gas? Slave won't ramp up if it can't keep the back pressure up. But yea defo sounds like u have either an inverter comp or board gone down or both.

Don't think it works of Back pressure. Work when suction pressure is within range.

Check all the thermistors are Reading correct I have had this problem previous.

Al

[Crash Pilot]

Capacity control is done by the pressure tranducers. If thermistors are out of there operation ranges then they can force the system into safety prevention mode to reduce capacity to try and overcome the problem.

The problem we shouldnt exclude is the previous faults that you have had with the inv compressor and PCB.

Good idea is to check these out because if you keep the system runing and the compressor has already burnt out and taken out the inv pcb or if it is on its way out you can end up spreading the contaminates throughout the whole system and other compressor. Huge clean up job.
Also unit have an emergency mode that when the system faults the customer can switch off via the controller and the outdoor will run for 8 hours with the faulty module locked out in emergency.

Better to be safe.

[Crash Pilot]

The above emergency mode is better described as Automatic Backup
Codes that will allow automatic backup.

E3 E4 E5 E7 F3 H7 H9 J2 J3 J5 J6 J7 J9 JA JC L3 L4 L5 L8 L9 LC U2 UJ

If customer has stopped and started the unit before you get out there then the reason why the unit may not be working could be because it is in automatic backup mode.

Not good for the system long term due to oil equalisation.

I would check inv comp

[Mentallist]

You can check if "Automatic Back Up" operation is active by pressing the mode button once on the outdoor PCB on the master unit. Display will change to H1P flashing, press return button x1 and if you then have H1P flashing and H5P on, then the "Automatic Back Up" operation is active. This can be reset by stopping the system and resetting power to the outdoor units.

[Reffnut]

You could try to force the slave to run by programing out the master condenser.

its hold mode till it goes solid
press set 38 times
return once
set once.
then return

set that in it will program out master condenser then slave will have to run.

if it is the slave going into L5 which is an inverter compresser fault, then you can program out inverter compresser on slave and try again.

Also it does sound like you could be short of gas.

[VRVIII]

Guys,

Fridgeymam posted his question 6 months ago, I think he'll have it sorted by now!

[Reffnut]

I did notice that after id posted....

[Crash Pilot]

How funny is that.
Hope he has it sorted or that would be one p$ssed off customer.
Was interesting post while it lasted