Daikin RUY5K1Y1 problems!

[Calais]

G'day guys,

In my travels I have come across one of these domestic units with intermittant faults that I have been unable to remedy permanently, wondering if any of you blokes could shed some light on where I might be going wrong, or if anyone has specific experience with such a domestic unit?

Basically its as follows, the original problem appeared to be that the A/C was low on gas & the leaks were around the flared connections on the condensor outside. The condensor's concrete pad had sunken about 40 mm over time as the soil compacted. After having the leaks fixed & the A/C regassed the A/C's condensor fan & compressor would not start. The service guy advised the compressor had burn't out. I got a second opinion the next service guy found the the main contactor to the compressor failed it's thermal overload.
Apparently the power supply from the main contactor also supplies the contactor on the condensor fan so that is why it also did not run.
I have had a new contactor & overload fitted today & the A/C ran for about an hour & it appears it has failed as well.
Can you give me some advise on what could be happening?

cheers,

[harleydavidnson]

i would check the following
1.was the the system recovered and evacuated
2.was the proper refrigerant loaded
3.was the proper amount of weighed charge installed
4.was allowance for pipe lenght considered
5.if above correct
6.compressor current should be measured to determine load
7.is compressor load above nameplate FLC
8.if current high why
9.is unit undersized for ambient and head pressure high
10.is the reversing valve ok
11. is the power supply low or missing a phase ./ use a megger to determine the condition of the compressor windings/ if single phase are the start and run caps of the correct value
12 all of the above need to be eliminated as possibilities
13. the underlying reason for the contactor failure or overload trip need to be identified

hope this helps