E5 alarm on Daikin 3MXS52E -outdoor unit.

Hello!

Outdoor :3MXS52EV1B
Indoor :2pcs FTXS25D3, one FTXS35D.

Customer's got several times alarm's on outdoor unit. Latest alarm was E5 when i checked. I reset alarm and connect RSUK0919 -monitor and test four hours. Everything seem's to be a normal and no alarms.
I put heating mode and 29 celsius set temp with autofan every three indoor units to get heavy load but no E5.
Totally pipe line is 55m and customer added 500grams R410a.

Sample of RSUK monitor's data :

OUTDOOR :
Freq HZ:102
Current :12,2 Amp (Max)
OutdrTH: 12,5 c
Heatex :1,5 c
DischTH :83 c
FinTH :31 c
OutFan :660rpm

INDOOR
Req Freq :F9
IntakeTH :29 c
LiquidTH :53
Fan :M

Have anyone guess what's causing problem?

I'm afraid that you are operating the system outside of the design specification.

The maximum allowable equivalent pipe length is 50m total, with a trim charge of 0.02kg/m above 30m.

If you have added 0.5kg, it is overcharged as well as over piped.

This is obviously putting a strain on the compressor at certain operating conditions, hence the E5 fault.

What is the level difference of the indoor units?

Quote:

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Originally Posted by frank

What is the level difference of the indoor units?

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Level difference is only 2m. (Residential house).

The only thing I can say then is that operating any system outside of the manufacturers recommendations will lead to unexpected situations.

Until the system has been modified to be within the limits, and then operating conditions compared, there is not a lot more to add.

What you are really asking at the moment is " is there anything I can do to make it work as it would if it were installed correctly?"

hello just confirming what Frank has said it is overcharged and has exceeded the manufacturers recommended pipe lengths.
Try decreasing the pipelength by five meters and take out 100 grammes.

Hi Basti,.
Sounds like your compressor is having problems. Did you check your voltage to the compressor when running?.
Your data looks like high currant for the frequency its at. Never a good idea to exceed the max pipe length.

Quote:

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Originally Posted by stuartwking

Hi Basti,.
Sounds like your compressor is having problems. Did you check your voltage to the compressor when running?.
Your data looks like high currant for the frequency its at. Never a good idea to exceed the max pipe length.

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.
They replace whole outdoor unit and it's have been working now about 2 weeks without any alarms.

Quote:

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Originally Posted by basti

.
They replace whole outdoor unit and it's have been working now about 2 weeks without any alarms.

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That is most dullness (and personally humiliating) option for any service technician.