Daikin inverter – are the pipes too long?

[Eugenie]

We had a Daikin inverter installed - outdoor unit: 4MX 80HV INB. 3 years later, just after the guarantee finished, the compressor burned out. We had a new compressor. Now just after 3 years the new compressor has gone the same way The company who installed it say it’s nothing to do with their installation and it must be due to variations in the electricity supply. We’re in France by the way.

One thing we did notice is that on the notice on the outdoor unit, it gives a maximum pipe length of 25 meters for a pipe to any indoor unit. One of the pipes is 28 meters long. We brought this up with the company and they said it makes no difference at all. Are they right or is it the pipe length that has caused the compressor problems?

[cool#9]

We had a Daikin inverter installed - outdoor unit: 4MX 80HV INB. 3 years later, just after the guarantee finished, the compressor burned out. We had a new compressor. Now just after 3 years the new compressor has gone the same way The company who installed it say it’s nothing to do with their installation and it must be due to variations in the electricity supply. We’re in France by the way.

One thing we did notice is that on the notice on the outdoor unit, it gives a maximum pipe length of 25 meters for a pipe to any indoor unit. One of the pipes is 28 meters long. We brought this up with the company and they said it makes no difference at all. Are they right or is it the pipe length that has caused the compressor problems?

SORRY DEAR RE MEMBERS MY ANSWER IS IN FRENCH !!! (IT'S THE FIRST TIME...).

Bonjour Eugenie et bienvenue sur le forum.
( c'est rare que je réponde en Francais mais ca change un peu ! ).
Concernant la casse du compresseur il faudrait connaitre aussi le denivelé c.a.d. la différence de niveau entre le groupe et les unités intérieures, la situation du groupe - en haut ou en bas - etc.
Il faut tenir compte aussi du cumule des longueurs. Aussi combien y a-t-il de circuits, quel genre d'unités intérieures - mural, console, encastrable - ?
Connaissez-vous aussi la cause de la 1ére panne par exemple: compresseur en court-circuit, en défaut d'isolement, comment la charge a été effectuée, y a-t-il eu des recharges intempestives ou des fuites de fluide ?
IL EST VRAI que 3 mt en plus sur un circuit n'est pas dommageable si le denivelé n'est pas déjà limite.
Lorsque qu'un compresseur casse, c'est souvent le résultat de plusieurs problèmes.
En espérant vous mettre sur la bonne voie.
Salutations
cool#9

[Eugenie]

Merci Cool – c’est plus compliquer que j’ai imaginé!

I’ll try to explain simply. The outside unit on the ground. There are 4 interior wall mounted units.

For the unit where the piping is 3 metres longer than the recommendation, the piping comes from ground level, goes up 5 metres, along the guttering and then comes down 2 metres and enters the house.

I don’t the reason for the first compressor failure but there was smoke. The second compressor tripped ( disjoncter) the electricity every time we turned it on. Two engineers came but didn’t know what the problem was.

As far as we know there have been no fluid leaks.

What do you mean by “denivelé” , not level?

[cool#9]

Merci Cool – c’est plus compliquer que j’ai imaginé!

I’ll try to explain simply. The outside unit on the ground. There are 4 interior wall mounted units.

For the unit where the piping is 3 metres longer than the recommendation, the piping comes from ground level, goes up 5 metres, along the guttering and then comes down 2 metres and enters the house.

I don’t the reason for the first compressor failure but there was smoke. The second compressor tripped ( disjoncter) the electricity every time we turned it on. Two engineers came but didn’t know what the problem was.

As far as we know there have been no fluid leaks.

What do you mean by “denivelé” , not level?
Ok see the attachment for details; "denivelé" is the level difference and if it is too high there will be a problem to recover oil into the compressor but it seems to be good in your case...
rgds
cool#9

[Eugenie]

Merci, c'est tres gentile.

[Eugenie]

Does anyone have any idea why two compressors should burn out after just three years?

I’m afraid to buy another in case it goes the same way. Each time it costs 2000 Euros. I’ve been told the compressors should last at least ten years ( 20 years by the company that sold the system to us!)

Would it be better to change the system completely?

[spurs6160]

Excessive pipe length can lead to bad or no oil return to the compressor which can lead to burn out.

Have both compressors burnt out or is the second one just down to earth?

What is the total run of all the units (ie add up the distance between the outdoor unit and all 4 indoor units) - this could also cause a problem if too long.

[lomb]

Kinks in the pipe, dirt in pipes , moisture due to non use of vacuum, pipes too long, too many bends, incorrect charge amount, incorrect charging procedure,putting compressor in without nitrogen purge,brazing without nitrogen etc. Could be anything ,or could just be bad luck?...

[cool#9]

Kinks in the pipe, dirt in pipes , moisture due to non use of vacuum, pipes too long, too many bends, incorrect charge amount, incorrect charging procedure,putting compressor in without nitrogen purge,brazing without nitrogen etc. Could be anything ,or could just be bad luck?...
Lomb you are right, they are so many ways to destroy a compressor, see my first RE album for reference on this kind of unit:
http://www.refrigeration-engineer.com/forums/album.php?albumid=284

cheers
cool#9

[aircon50]

Hi Eugenie.
Have checked install info for 4MX 80. The maximum total pipe length is 70m. Maximum individual length is 25m. Maximum height difference from outdoor unit to any indoor unit is 15m, and maximum difference in height for any two indoor units is 7.5m.
Given that you have a 5m rise and then 2m drop into the house takes care of 28m (5 + 2 x 4), out of your total of 70. This leaves an average of 10.5m left for each indoor unit.
One problem (of many), as has already been mentioned, is that of oil return to the compressor. Taking a quick mental snapshot of the installation, the suction line has, (probably) a reasonably horizontal run and then a 2m rise before a 5m drop. Here's where the problem starts. The oil velocity will have slowed in the long pipe run, and only some will be carried over the 2m rise, leading to a shortage of oil at the compressor, with the resultant mechanical/electrical consequences.
Personal opinion only - installation.
Best regards, Graham

[Eugenie]

Thanks guys that’s really helpful


The total piping length is 79.9 metres give or take a few centimetres with the longest being 28 metres.
The length between the first and last interior unit is about 40 metres
For 3 interior units there 3 bends plus where each one goes through the wall. The other unit, the longest, has 4 bends plus where it enters the wall.

I think one compressor breaking down would be bad luck but 2 going after approximately 3 years must be bad installation.

[Eugenie]

Dog’s breakfast!

If you look at this webpage you’ll see the dog’s breakfast they made of the installation. No protection for the pipes and just black tape where it enters the house.

bordeaux-holiday-rentals.com/General%20Equiepement%20installation.htm

[Eugenie]

you need to add "www" to the address in my previous post!

[Eugenie]

Here's a photo.

Where the pipe enters the house it's wrapped only in black tape.

What do you thinK?

[nike123]

Failed compressor should be opened and checked for cause of failure. That will tell for sure if you have problem with oil return or some other problem.

[back2space]

Looking at that picture I think there is a problem with the installation.

The pipes on thew all are not straight they dip in the middle so oil could get stuck here and not get back to the unit, it should be straight so that the oil can follow a straight line.

Oil could collect here in the pipes.

[Sridhar1312]

In a hotel in Chennai (South India) Daikin VRF more than 20 compressors failed and client had sued DAIKIN for the frequent fai;ures. Daikin had got the installation inspected by Japanese service engineer who was bewildered and has given the reason for failure as High ambient. In chennai ambient dry bulb temperature goes beyond 35 degree C only for 352 hour out of 8760 hours in a year.
probable reason for failures could be lack of oil i.e. oil return especially when the system operates on part load.Still the VRF/VRV almost all manufacturers are making aggresive selling and clients are trapped especially in INDIAN Market where it is not suitable as most of the places it is as cooling option only. I feel VRF performance is more suited for Heat pump applications

[nike123]

http://www.danfoss.com/BusinessAreas/RefrigerationAndAirConditioning/News/Refrigeration+Articles.htm

[Andy]

Does anyone have any idea why two compressors should burn out after just three years?

I’m afraid to buy another in case it goes the same way. Each time it costs 2000 Euros. I’ve been told the compressors should last at least ten years ( 20 years by the company that sold the system to us!)

Would it be better to change the system completely?
Hello Eugenie:)

I would start with the electric cabling both to the fuse board and the cable frome the fuse to the units.

Measure the voltage at the outdoor unit, especially when the compressor is starting.

Although the piping is not perfect, the fact that the outdoor is lower than the indoor unit should almost rule out the possibility of it being piping related.

Kind Regards Andy

[multisync]

Hello Eugenie:)

I would start with the electric cabling both to the fuse board and the cable frome the fuse to the units.

Measure the voltage at the outdoor unit, especially when the compressor is starting.

Although the piping is not perfect, the fact that the outdoor is lower than the indoor unit should almost rule out the possibility of it being piping related.

Kind Regards Andy

As it's an inverter I would doubt voltage drop on start up...

As an aside I would expect the compressor(s) to be under warranty!

[Andy]

As it's an inverter I would doubt voltage drop on start up...

As an aside I would expect the compressor(s) to be under warranty!

Hello Multisync:)

yes valid point on the inverter. I still have doubts about the electrics supplying the unit.

The other obvious things would be air and moisture from a bad install.

The compressor would only be warranty, if it was under a year old, with no other fault in the system.

I know that the warranty is quite a lot longer if the installer is D1.

Kind Regards Andy:)

[multisync]

Hello Multisync:)

yes valid point on the inverter. I still have doubts about the electrics supplying the unit.

The other obvious things would be air and moisture from a bad install.

The compressor would only be warranty, if it was under a year old, with no other fault in the system.

I know that the warranty is quite a lot longer if the installer is D1.

Kind Regards Andy:)

The picture shouts lowest bid.:confused: But yes fluctuating voltages can easily cause problems but I thought they had a error code for that?

The install should be looked at by a Daikin tech or someone who can carry that authority ( Cool9 etc)

D1 was introduced by D.UK and as such is not applicable in this instance....

[Steve J C]

Sag in pipework will hold oil. Should be re-done, System purged with nitrogen and burn-out filter + acid away or similar treatment before replacing compressor.
Suggest replacing your contractor before replacing compressor.

[nike123]

Sag in pipework will hold oil. Should be re-done, System purged with nitrogen and burn-out filter + acid away or similar treatment before replacing compressor.
Suggest replacing your contractor before replacing compressor.

If first compressor is burned and system is not adequately treated, it is normal that second burn out occurred.
Sag on picture hardly can hold oil because of refrigerant speed.

[R1976]

Why are so many bothered about a sagging pipe?

Split system pipework often has to follow the building construction and I have seen and put sets in many pipes without any problems as long as the manufacturers instructions are followed.

There are many bodgy installs in England where pipe has been "thrown" into ceiling voids.

[Eugenie]

Here are some more photos

[Eugenie]

and some more

[Eugenie]

Thank you everyone for your comments.

It seems that:

firstly the company that installed it should have checked their installation when the first compressor broke.
then they should have examined the compressor to see what the problem was.

Their answer has always been it’s EDF’s (electric company’s) fault because of electricity fluctuations.

The obvious thing to do now is to ask Daikin to examine the installation and compressor.

[back2space]

How many meters of pipework are there from outdoor to indoor in total?

YOu mention that there is about 8 metres before it enters the house but it seems like it travels some distance inside the house also.

[Makeit go Right]

Have checked install info for 4MX 80. The max total pipe length is 70m. Max individual run length is 25m....regards, Graham


The total piping length is 79.9 metres with the longest being 28 metres. The length between the first and last interior unit is about 40 metres. The longest run unit has 4 bends plus where it enters the wall.

Looks like excessive runs leaves the installer culpable.

You must change something before installing the third compressor. Something is killing off these compressors and just popping a new one in is, well, wasteful.

At least, rerun the pipework so it is all within spec range (ie within run-lengths) and do a good clean up as mentioned above.

As for the power issues being the who, the installer would need to offer some evidence of that, such as fault codes in the history, if these are available. And if none are there, it comes back to run lengths, at least.

Getting the dead compressor checked out is also a sensible thing to do, though someone needs to pay for the work, of course. (cheaper than the cost of the next compressor change, though.)

[back2space]

Yes that excessive pipe run is deffo the cause of your problems.

[Eugenie]

Re pipe run, there are about 79 metres supplying 4 indoor units. With one pipe being 28 metres when the maximum is 25 metres.

However, Daikin say this wouldn’t cause the compressor problem.

The compressor is in the garden. The pipes cross into an outbuilding at the back of our house, and then through the walls of the house.

[nike123]

However, Daikin say this wouldn’t cause the compressor problem.


Pretty much correct if all other limits and pipe laying rules are respected.
But, I have simmilar installations and in few cases compressors did not survived many working hours (3-5 years with low usage).
When opened, it was obvious that they have had poor oil return. And in all cases with fallen compressors, outdoor unit was above indoors.
My conclusion is: if you are approaching (and crossing) length limits, you are shortening compressor life.

[back2space]

Pretty much correct if all other limits and pipe laying rules are respected.
But, I have simmilar installations and in few cases compressors did not survived many working hours (3-5 years with low usage).
When opened, it was obvious that they have had poor oil return. And in all cases with fallen compressors, outdoor unit was above indoors.
My conclusion is: if you are approaching (and crossing) length limits, you are shortening compressor life.

It looks as though the outdoor unit is installed below the indoor units according to one of the pics above?

Would oil return still be an issue?

[Makeit go Right]

pipe run is about 79 metres supplying 4 indoor units, with one run being 28 metres when the maximum is 25 metres.
Daikin say this wouldn’t cause the compressor problem.

Hmmm. That's not normally the kind of answer one gets from Daikin when compressors are falling over. They tend to jump on any system outness to void a possible warranty claim.

Did they write that in a letter?

[jayesh_famt]

during each failure of compressor are they fill fresh oil in the system or any top up . oil should me used same grade only.

[nike123]

Would oil return still be an issue?
I would say not as much as when it is above.