Problem with REYQ12P8Y1B D.T.E. !

[cool#9]

Hi
Well i'm back with a brand new problem.
I made a commissioning in the mid of december '09 with a REYQ12P8Y1B + 15 BSVQ100P + 15 indoor units.
Run test ok, no cross pipe, controled by service checker.. etc..etc..
The system ran well in heating mode 'til this week and now i've got the 2 compressors Down To Earth .
My question is what are the real reasons to get 2 comp in this state after just one month ?
I'll change both comp next week after complete gas recover, i plan to send oil sample in a laboratory to check moisture+acidity and maybe more ( we have "dph climalife in France").

Any advise much apprecied
rgds
cool#9

[Clk320_Greg]

Hasnt been hit by lightning or something daft has it?

[cool#9]

Hasnt been hit by lightning or something daft has it?

No.. in fact they are also 8 REYQ with a total of 122 units on the same power supply.
rgds
cool#9

[cool#9]

Hi, well i feel i'm speaking to myself!!!
Anyway i fully recovered R410A and 4 kgs has gone since the 1st commissioning... also we've found that they forgot to add refrigerant for the 1/2 pipe roughly 3.6 kgs... so 7.6 kgs missed (or "ran out" i don't know what's the english for).
There wasn't oil left in the inverter compressor !!! but a lot in the standard one...
The question is : the 2 compressors failed down to earth due to a shortage of refrigerant ?
And what about the very low oil level in the 1st compressor ?
Actually the whole system is under nitrogen gas to find out leaks... maybe you could help before i start the system (next week probably)
rgds
cool#9

[El Padre]

Hi Cool #9

Could it have been put into emergency operation after the first compressor failed?

We are back to this whole oil charge/dont charge scenario again, has the system got a centralised controller and if so is there a schedule set up for it?

I am wondering if it got left running over weekends continuosly under minimal load conditions, are the refnet joints fitted correctly (the correct plane)?

Ciao

[cool#9]

Hi Cool #9

Could it have been put into emergency operation after the first compressor failed? >No they failed together also only L5 in the outdoor fault memory.

We are back to this whole oil charge/dont charge scenario again, has the system got a centralised controller and if so is there a schedule set up for it? >No

I am wondering if it got left running over weekends continuosly under minimal load conditions, are the refnet joints fitted correctly (the correct plane)?> yes probably under minimal load but the refnets are right

Ciao

Thank you cool#9

[VRVIII]

Hi, well i feel i'm speaking to myself!!!
Anyway i fully recovered R410A and 4 kgs has gone since the 1st commissioning... also we've found that they forgot to add refrigerant for the 1/2 pipe roughly 3.6 kgs... so 7.6 kgs missed (or "ran out" i don't know what's the english for).
There wasn't oil left in the inverter compressor !!! but a lot in the standard one...
The question is : the 2 compressors failed down to earth due to a shortage of refrigerant ?
And what about the very low oil level in the 1st compressor ?
Actually the whole system is under nitrogen gas to find out leaks... maybe you could help before i start the system (next week probably)
rgds
cool#9

Hi Cool#9,

Did you remember to use reclaim/vac mode (mode 2 setting 21) when recovering refrigerant? If this is not used there will be 4~8kg of refrigerant trapped in the regulator tank.

Did the failed compressors:

• Show any signs of overheating?
• Any signs of burning at electrical terminals?
• How much oil did you remove from compressors?
• What is the pipe run length from outdoor to furthest indoor?
• Is there fresh air supply ducted to indoors?

I would also check:

• The reversing valves (Y8S/Y9S) are wired correctly and coils are fitted to correct valves.
• The expansion valves are wired correctly and motors are fitted to correct valves.

[brunstar]

It seems weird that the refrigerant charge was not calculated properly.
Was OFN used when the system was installed?
check the colour of the oil in the compressors which were replaced, it is most likely black.
What is the level difference on the outdoor unit? is it only one outdoor unit?
If there is no oil left in the compressor it makes sense being 8kg short of refrigerant and the liquid injection being energised all of the time to make sure that the compressors are being cooled down, which in turn may have flushed all of the oil out of the compressors.
If you are over the maximum rule for height difference or first ref net to furthest fan coil, oil recovery may not have worked properly either.

[cool#9]

Hi Cool#9,

Did you remember to use reclaim/vac mode (mode 2 setting 21) when recovering refrigerant? If this is not used there will be 4~8kg of refrigerant trapped in the regulator tank. > yes i did but i'm not sure the regulator tank's EV is open in this mode: i have to check on the field then this will explain the wrong recovery at the first time.


Did the failed compressors:

• Show any signs of overheating? > the insulation on the hot gas pipe was a little bit burn i admit
• Any signs of burning at electrical terminals? >no
• How much oil did you remove from compressors? > inv= almost empty / std= roughly 2.5 lt
• What is the pipe run length from outdoor to furthest indoor? > it is about 50 m
• Is there fresh air supply ducted to indoors? >no

I would also check:

• The reversing valves (Y8S/Y9S) are wired correctly and coils are fitted to correct valves. > i will do it again
• The expansion valves are wired correctly and motors are fitted to correct valves. > i will check again

Thanks a lot
cool#9

[cool#9]

It seems weird that the refrigerant charge was not calculated properly.
Was OFN used when the system was installed?
check the colour of the oil in the compressors which were replaced, it is most likely black.
What is the level difference on the outdoor unit? is it only one outdoor unit?
If there is no oil left in the compressor it makes sense being 8kg short of refrigerant and the liquid injection being energised all of the time to make sure that the compressors are being cooled down, which in turn may have flushed all of the oil out of the compressors.
If you are over the maximum rule for height difference or first ref net to furthest fan coil, oil recovery may not have worked properly either.

Hi Brunstar and thanks for the reply..
Do you mean there's a liquid injection to cool down the compressors like the old models..? it's a new on me. In fact we do not have any compressor failure on P series HR...now i 've to go further..i'll read the service manual again.
For the rest it's correctly fitted ( length, refnet position, etc)
The small amount of oil in the inv comp was likely black.
Kind regards
cool#9

[VRVIII]

Did you remember to use reclaim/vac mode (mode 2 setting 21) when recovering refrigerant? If this is not used there will be 4~8kg of refrigerant trapped in the regulator tank. > yes i did but i'm not sure the regulator tank's EV is open in this mode: i have to check on the field then this will explain the wrong recovery at the first time.

cool#9

The refrigerant regulator tank does not have an EV, the tank is used to adjust the system refrigerant charge as required. The level is controlled by 3 solenoid valves (Y1S, Y3S & Y7S) these will open when reclaim/vac mode is used. The tank is located in the right side of unit and the 3 solenoid valves are next to the tank mounted at base of unit.

How much oil did you remove from compressors? > inv= almost empty / std= roughly 2.5 lt

I would also check the oil return line between oil separator and suction line. Blow OFN through line to verify there is no blockage in the capillary or filter.
However your system has been operating 30~40% short of refrigerant which will effect the oil return operation (low suction press=low velocity for oil return). Did you inspect the controller fault history? I'm sure you will find previous F3 errors, if these had been checked out it would've the prevented compressor failures.

Hi Brunstar and thanks for the reply..
Do you mean there's a liquid injection to cool down the compressors like the old models..? it's a new on me. In fact we do not have any compressor failure on P series HR...now i 've to go further..i'll read the service manual again.
For the rest it's correctly fitted ( length, refnet position, etc)
The small amount of oil in the inv comp was likely black.
Kind regards
cool#9

VRV3 heat recovery does not have liquid injection, the unit will reduce the subcooler target superheat to 0.0 K acting like a liquid injection. However if the suction/discharge superheat is high this would not cause liquid return or flush oil from compressors, these are high press shell compressors and the oil sump is in high press side.
It's also worth checking the crank case heaters are operational and wired to correct connection on PCB.

[cool#9]

The refrigerant regulator tank does not have an EV, this is used to adjust the system refrigerant charge as required. The level is controlled by 3 solenoid valves (Y1S, Y3S & Y7S) these will open when reclaim/vac mode is used. The tank is located in the right side of unit and the 3 solenoid valves are next to the tank mounted at base of unit.

Hi VRVIII, i'm back with my problem and it's seems that only SVL/Y3S & SVG/Y1S are open during refrigerant recovery mode (see attachment) because we didn't find any leak on the field at that time.This will explain there was maybe refrigerant inside the regulator tank AND WE SURELY NEED TO ACTIVATE SVO / Y7S. Or.. maybe i'm wrong if they mean it's the surplus of refrigerant that will be recovered (anyway i'll check on the field).
Also i maybe have a problem with SVT/Y6S about the oil level inside the inverter compressor (i don't find in which case this ev is used, maybe you could help ).
Let's say it's not the very first time i've heared engineers did not find the correct amount of refrigerant while recovering this kind of units.
Your remarks and advises sould be helpfull.
rgds
cool#9

[VRVIII]

Hi VRVIII, i'm back with my problem and it's seems that only SVL/Y3S & SVG/Y1S are open during refrigerant recovery mode (see attachment) because we didn't find any leak on the field at that time.This will explain there was maybe refrigerant inside the regulator tank AND WE SURELY NEED TO ACTIVATE SVO / Y7S. Or.. maybe i'm wrong if they mean it's the surplus of refrigerant that will be recovered (anyway i'll check on the field).
Also i maybe have a problem with SVT/Y6S about the oil level inside the inverter compressor (i don't find in which case this ev is used, maybe you could help ).
Let's say it's not the very first time i've heared engineers did not find the correct amount of refrigerant while recovering this kind of units.
Your remarks and advises sould be helpfull.
rgds
cool#9

Hi Cool#9,

When using reclaim/vac mode there is no need to energise solenoid valve Y7S (SVO) to allow refrigerant reclaim. This valve allows flow from refrigerant regulator tank to suction line but passes through a capillary tube which would restrict the flow. During normal operation this is used to remove refrigerant from regulator tank, increasing system charge.

When using the reclaim/vac mode Y1S (SVG) must be open as this allows a direct flow path from regulator tank to suction line when energised. During normal operation this is used to reduce regulator tank pressure by purging gas from top of tank, this would then allow liquid to flow into tank when Y3S (SVL) & Y1S (SVG) are energised. Adding refrigerant to regulator tank, reducing system charge.

The reclaim/vac mode will also fully open all outdoor, BSVQ-P & indoor EEV’s.

Solenoid valve Y6S (SVT) is not used during normal operation.

Also remember the reclaim vac mode will be automatically cancelled when then mode button is pressed to exit or when mains power is switched off or reset.