Hitachi utopia fault code 39

[n1redrum]

Hey, having real proplems with a hitachi utopia heatpump single phase. Initially the condensing unit had been tapped by a truck and lost its gas, so repaired and regased. but now error code 39 keeps coming up (overcurrent) so checked the amps to the comp which is fine, so is the current transformer. Then thought maybe a blockage in the system or overgased, so reclaimed and blew nitrogen through (no blockage) then tried running the comp (single phase) unpiped and pressure switches over ridden but power is still tripping to the contactor stopping the compressor. everytime i reset on isolator comp runs for about 3 seconds and then this happens. im a little stumped so any links or help would be apprieciated.

[superswill]

welcome the RE n1redrum,

ok so lets get right into it,by power tripping to the contactor do you mean an overload or at the MCB?

[n1redrum]

just the contactor inside the condensing unit that supplies the compressor (CMC ?). Losing the 240v that makes it A1, A2. so it must be some sort of safety switch cutting it out ???

[The Viking]

Hmm...

You got an Utopia INVERTER??

If so there will be more to it than a contactor...

There might be a contactor feeding the inverter or maybe it isn't an inverter unit as stated in your first sentence??

If you clarify this, I'm sure the advice we will provide you with will become more accurate.

Cheers

[n1redrum]

S**t, my apologies. its just a run of the mill single phase heatpump, ive been working on an Danfoss inverter aswell today and my heads right up my backside.

[superswill]

S**t, my apologies. its just a run of the mill single phase heatpump, ive been working on an Danfoss inverter aswell today and my heads right up my backside.

lol,ok give us the heads up on the split then

[n1redrum]

everything i put in my first thread refers to the heat pump im having problems with.

[n1redrum]

can you tell ive never written on a forum before, i might just start the whole thread again.:confused:

[superswill]

can you tell ive never written on a forum before, i might just start the whole thread again.:confused:


lol dont worry iam sure we can get you though it,ok what i get so far,split gets bashed,repair leaking,pressure test vac charge ect ect,run system faults on comp over curr and is triping MCB

[n1redrum]

no not on mcb, there is always 240v to the unit. The compressor starts but runs for a few seconds and then cuts out. when the compressor has cut out 3 times the error code 39 (overcurrent) comes up

[superswill]

got it!

id start with checking the compressor.if unsure of how to see:

http://www.refrigeration-engineer.com/forums/showthread.php?t=12514&highlight=checking+compressor+windings

[n1redrum]

windings are fine. and the current the compressor is pulling is also fine. if you push the contactor in the compressor runs. but the voltage to hold the contactor in is cutting out, therefore the compressor cuts out

[superswill]

sounds like a faulty contactor,have you checked the voltage at the top and bottom of it?

[n1redrum]

i checked so many things i cant remember, im pretty sure its ok. one of the relays on the pcb clicks and then the power supplying the contactor cuts off.

[superswill]

i checked so many things i cant remember, im pretty sure its ok. one of the relays on the pcb clicks and then the power supplying the contactor cuts off.


is this during normal op?

[n1redrum]

there is 240V going through the contactor to the compressor when it is made. 240v supplying it but the 240v supplying it is being cut off after a few seconds when a relay on the pcb clicks

[n1redrum]

set to cooling on the dip switch

[superswill]

set to cooling on the dip switch


PM sent with number as suffering with slow net sindrome

[TRASH101]

There is an over current relay on hitachi utopias settings are :

For ras 2 17A
ras 2.5 20.5A
ras 3 25A
ras 3.5/4 32A + 17A (for cold/prolonged sarting)

You need to measure your peak starting current and if ti doesnt drop to under the relays setting within 2 - 3 secs then you will get fault 39 thereby indicating a charge or compressor fault (or power). The relay maybe faulty but difficult to test properly unless you have the equipment.

[omurcelik]

as far as see from the service manual current sensing for comp motor aligning from current coil ct to outdoor unit pcb cn6 socket so i think as an electronics technician there is an operational amplifier measuring that current value so pull out that cn6 socket from pcb thats way u can be sure that this is a pcb fault or not if its again giving that fault code replace or repair that pcb maybe current coil burnt so be measuring wrong value if it is working without ct (current coil) u cant be sure if pcb faulty or not...good luck