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Grizzly
19-06-2017, 05:28 PM
Hi Guys can anyone help.
Called out today to the above chiller with a Pro dialog Plus controller.

This chiller was first looked at last week. when my colleague found the chiller was randomly shutting down from Remote run to Local off.
I believe He disconnected and reconnected the BMS remote run wiring connection repeatedly without replicating the fault.
Having remade some wiring connections also, believed that the issue may have been solved!

Anyway, when I got to site the chiller had kicked in and was running on remote run.
However, it had not started until around 0900hrs. which meant that the chilled water circuit was above 30c.

Yes Guys!
We are having a miny heat wave over here in the U.K. I clocked 33c on the motorway.

So the chiller was working around its setpoint of 7.0 and averaging a 1c split across the chiller.
The customer was happy for me to leave the chiller in Local on for the foreseeable future.
Having switched the control across to local on and whilst waiting for the water temp to climb to the sp + diff. = 12c.

The controller dropped out to Local Off!
Reset again and it ran / runs Happily?

This site also has huge amounts of Air in the chilled water circuit.
On investigation the last 10 Historical Alarms were P-14 "Cooler Interlock Fault".
They may of been caused by my colleague trying to prove/ replicate the Fault.
Or not!
Anyone got any idea
Thanks Grizzly

I think I may have the answer guy's
I just found this reference.

P-14 Water flow control and customer interlock fault Automatic if the unit is in manual
shut-down status, otherwise
manual.
Evaporator pump defect
or water flow switch fault
Unit is shut down

What do you think.

Grizzly

Gibbo
24-06-2017, 01:08 PM
Don't know why I missed this can only say I'm recovering from standby and the heat last week
. If chiller shuts down on flow failure when in BMS control it will only restart once flow is confirmed pumps usually form part of BMS signal. If in local control the chiller only looks at its own controls it will attempt a restart if it trips on flow even if no flow but will do an immediate shutdown again .but will then lock out on flow if it continues to trip.

Gibbo

Grizzly
24-06-2017, 01:36 PM
Thanks for the input Gibbo.
Your input is really appreciated.
I was only thinking this morning, I must phone the customer on Monday for an update.
I know what you mean about last week.
I managed a 26/27hr straight shift mid week, despite not being on call. My colleagues all doing similar!
Mad week and it may continue?
Cheers Grizzly

Grizzly
27-06-2017, 07:06 PM
A quick update Guys.
I spoke with the boss of the Facilities company that I looked at the above chiller for.
He said it was indeed poor water flow / Air in the system.
They carried out extensive bleeding throughout the water system and replaced the AAV's.
Bingo apparently they have a very happy customer (Office Block) and He is happy with "Us!"
A good day at the office.
Cheers Grizzly.

FaultCode
27-06-2017, 07:17 PM
Congrats all round then, who supplies the doughnuts?:)

frank
27-06-2017, 07:52 PM
Congrats all round then, who supplies the doughnuts?:)
Virtual or real? ;)

Grizzly
27-06-2017, 09:47 PM
Doughnuts!
That would require recognition of a job well done!
Grizzly