Daikin split help - Refrigeration-Engineer.com forums

maxcool · #1 28-07-2010, 03:30 PM

Attended a site this morning briefly and found a 410a split system (rr100b8v3b) and found it with an e0 fault. Re-set the system. When the system starts up, condenser fans starts and then when it pulls the contactor in for the comp to start, the contactor gets thrown straight back out. The compressor does not even vibrate etc. The suction guage does not budge at all when the compe attempts to cut in. Once this happens, the fan cuts out straight away hpwever it does not go into fault.

I was expecting perhaps for the comp to trip the breaker but nothing. The e0 fault has not cut in since either. Just seems that the comp will refuse to run.

Any detailed checks or advice that anyone can give me for this.

Many thanks in advance.

ktm · #2 28-07-2010, 04:13 PM

Eo is activation of outdoor Safty device could b termal cut out on comp?how does it feel? Just go through the diagram and check with a meter which Safty is open.

**frank** · #3 28-07-2010, 08:29 PM

Your profile says that you are an A/C engineer. Do you know how to test a compressor?

ktm · #4 29-07-2010, 11:38 AM

It's one of the units Safty devices that us stopping it from running. That's why it seems like it just refuses to run as u say yourself. Just go through all the Saftys in the diagram with a meter and find which is open. I'm with frank on this. U know what u are looking at???

Crash Pilot · #5 01-08-2010, 06:58 AM

Sounds like the compressors tripping it. If any other safeties are tripped the unit won't try to start. Havn't seen this model however it looks like it may be a single phase 4hp. Disconnect the compressor from the contactor and see if it holds the contactor in then.
This will tell u if it is compressor or starting circuit for compressor.
If single phase check that unit does not have soft starter.

Crash Pilot · #6 01-08-2010, 07:17 AM

O.k just found a wiring diagram. This unit is single phase and also has a current transformer. Some of the older Daikin stuff would show a eo fault from the current transformer (Different to new models).
If the contactor is pulling in and you are not noticing the compressor kick then it is not getting voltage or the compressor has open windings . This will cause the CT to activate and shut the unit down after about 1-2 after the contactor pulls in.

Put a clamp tong on the compressor and a meter across the load side of your contactor and see what happens when the contactor pulls in.

maxcool · #7 05-08-2010, 11:43 AM

Thanks crash pilot. This is helpful advice so thank you for your time on this.

Regarding Frank and Ktm comments, when i signed up to this site i didnt see anywhere that said i had to know everything. I have only previously done split a/c installs before so this is all new and just want to learn as much as possible hence the post asking for help. I see a lot of help posts from other members and just because this is a simple post compared to others, shouldnt mean i cant post without getting replys from experienced guys questioning my abilitys. I just required a reply like the above one to help me in the right direction.

Crash Pilot · #8 05-08-2010, 12:13 PM

maxcool

Always happy to help. Main concern people have giving out advise is making sure the person on the other end is qualified and knows the dangers of what they are working with.
I have had friends and work collegues die in roofs and under houses hooking themself up to live power and they were experienced. Just careless.Don't know what your licence requirements are. If you are not licenced then I recommend you find someone that is.
If you are licenced then always exercise caution.
Always happy to help. Everyone has to start somewhere.
Alot of smart people on this site. Work it like a sponge and soak up as much knowledge as you can.

**frank** · #9 05-08-2010, 12:19 PM

Your profile says you are an engineer and I assume therefore you would be able to trace out a bad compressor
Are you qualified or still training?
No offence intended by the way

brunstar · #10 06-08-2010, 08:44 PM

Leave him alone...
It is a 10kw single phase unit, if the compressor is pulling in. like the other posts said then check the current, if the compressor sounds like it is not starting then you may find that the capacitor is faulty on the unit hence the reason the current sensor is sensing the prolonged excessive start up current and locking out.
Check the dielectric strength of the capacitor before condemning the compressor.

Dunger83 · #11 19-08-2010, 12:06 AM

With the 'B' series Skyair the E0 error can only be generated by one of two things.
A) Fan motor overheat - there is an internal thermal protector within the motor. (2 grey cables in the fan loom are for the klixon)
B) The compressor itself (overloading).

Please note - If a spare part PC board has been installed please check that the corrct jumpers have been cut.
There is a requirement to cut certain jumpers for different functions. example, to tell the PC board the the machine is either a cooling only/or heat pump, single phase/or 3 phase.

If the wrong jumper is cut then the PC board may be looking for the current value of the wrong size motor.

Just a thought - hope this helps.