Error 516: Heat pump missing

Hi,

I am trying to start up my brand new air-to-water Heat Pump, model WOYG 112 LCT, 3-phase type 50 Hz 400 V.
When I switch-on the indoor unit I keep getting the following message on the display:
State Heat Pump Fault
After pressing the information key, I get:
Error 516: Heat pump missing
I checked the outdoor unit which is also in error mode with the red LED blinking fast. When I press the ENTER switch, on the outdoor unit, the red LED blinks one time in 3 seconds, constantly.

I do not have detailed service documentation in order to interpret the state of the heat pump and proceed with startup.

How to proceed? Where can I find a detailed troubleshooting document describing this behaviour?

Thanks and regards
Milan

What make of heatpump are we talking about here?

Generally, you would expect to see power supply to both indoor unit and outdoor unit then there would be an interconnecting cable between the two carrying the communications.
The terminals would normally be labelled something like:
N-L1-L2-L3 This is your power supply
A-B-C or 1-2-3 This is the communications (Note, it might just be one comms terminal or there might be as many as 4)
It is important that there are no breaks or switches in the comms wiring and also that it not is crossed, i.e. that A in the outdoor unit is connected to A in the indoor unit and so on.

But, your best bet to get the proper manual is to either search the manufacturer's website or contact their local importer/supplier.

:cool:

It is Fujitsu heat pump.
Yes, the power supply of the external unit comes from the internal unit.
The communcation bus consists of 2 wires and there are signals going back and forth. Actually, there are 4 wires: L, N, COMM and earth on the indoor unit connected to 1, 2, 3 and earth on the outdoor unit. I am sure we got that right. However, I am not able to get the system started.
Is the phase order important (it is an inverter heat pump)?

I searched for manuals, found some but I need really detailed information how to troubleshoot starting from the error message "Error 516: Heat pump missing".

You state that there are 4 wires from the indoor to the outdoor and that the indoor is powering the outdoor.

How is the 3 phase power getting to the outdoor unit down the L and N leads?

Quote:

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Originally Posted by Brian_UK

You state that there are 4 wires from the indoor to the outdoor and that the indoor is powering the outdoor.

How is the 3 phase power getting to the outdoor unit down the L and N leads?

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Only the outdoor unit has its 3 phase power supply not the indoor.
The L&N leads supply power from the outdoor to the indoor unit. The other 2 leads are commincation and earth.
Sorry if I was not clear enough.

As an engineer myself, I need a detailed service manual to read and understand how to proceed to tackle and solve the problem.

Quote:

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Originally Posted by MilanIgnjatovic

Only the outdoor unit has its 3 phase power supply not the indoor.
The L&N leads supply power from the outdoor to the indoor unit. The other 2 leads are commincation and earth.
Sorry if I was not clear enough.

As an engineer myself, I need a detailed service manual to read and understand how to proceed to tackle and solve the problem.

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To Brian_UK:
How do I tackle the the ERROR 516: Heat Pump missing?
I need an answer!

Thanks for your help
Milan

Dear Milan,
Please understand, on this board you will find experienced engineers willingly sharing what they learnt over their (sometimes very long) careers.

If you

Quote:

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Need an answer!

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the place to go is wherever you bought your equipment from, they are the people that should know the equipment better than anybody else and who also got a legal obligation to help you.

Quote:

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Originally Posted by The Viking

Dear Milan,
Please understand, on this board you will find experienced engineers willingly sharing what they learnt over their (sometimes very long) careers.

If youthe place to go is wherever you bought your equipment from, they are the people that should know the equipment better than anybody else and who also got a legal obligation to help you.

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OK, my understanding of what you are trying to say is :"I don't know how to help you with your problem".
Fair enough, but thanks for trying. I am just surprised that nobody on this forum experienced this kind of problem.
When I solve it I'll come back here and let you know so we can all have something from it.

Thanks and best regards
Milan

Getting helpful ideas. Thanks people for taking your time to share positive replies.