Carrier CCN Control

[troymedhurst]

Hi, calling all carrier bods.
Have problem with two chillers not running under CCN control:confused:
In Brief, I ave two 30gh 150 air cooled chillers, both have Flotronic System Manager inside. In one it also has another Flotronic System Manager that is connected to the other two FSM's by means of three wire bus. I set the chillers toggle switch to CCN, but only reads CCN off, The main FSM has a toggle switch connected to 20,21, which can turn CCN on and Off. It also has a 24v enable to 25,26- all ok. The other imputs to this are chwst, chwrt and OAT temp sensors , all within range. I have checked field configs and there is no dual setpoints or external resets. I have two buildings the same and one seems to work on the CNN. I have been trying to use the working system as a benchmark to no avail, the only difference i found was that when I disconnected the inputs to the main FSM an alarm came saying lost communication with the CCN. It did not do this on the other two systems. How do I know it is communicating? What can hold off chiller under CCN Off status, any ideas greatly recieved. Thanks Troy

[Grizzly]

Check your mail my friend.
Page 18 24 and table 12 will help HOPEFULLY?
Refer to the attached.
Grizzly

[troymedhurst]

Thanks Grizzly,
Only got Table 12 Link not the other Pages. This table is different to the manual I have, but explains a little more. What do they mean by LOR switch. LOCAL OR REMOTE maybe?

[troymedhurst]

When the switch is in Local the display reads 'Local On' the unit runs normally. Set it to 'OFF' and the display reads 'Local OFF', when I set it to 'remote' or 'CCN' it reads 'CCN OFF' even though the remote contacts are made and LWT is up @14oC ? Something is holding it off, but what?

[troymedhurst]

Sorry forgot to say it has a Flotronic 2 Display and keypad, if this makes a difference.

[Grizzly]

Troy check your email not the post!
Grizzly

[Gibbo]

If your sure that terminals 20,21 are made (try a jumper) and you have measured 24 volts at terminals 25,26 the only other external possibility is one of the main sensors being out of range but you can compare it with one of the chiller water sensors otherwise your only hope is to get Carrier Service onsite with a laptop.
You could check the power and comms lights on the top of the FSM are working, red (power)and green (comms) should both be flashing if not then most likely the FSM will need replacing also possible the battery back up for retaining the memory is faulty either way your best bet is to just get Carrier onsite.
There is another problem and these modules (called PSIO'S) are no longer made and are obsolete which means you would need to send your PSIO off for repair to Carrier.
Without a laptop to see the program inside the FSM your just pissing in the wind.
Where are you located ?

[troymedhurst]

thanks Grizzly I got mail, I already have these manuals and cannot find anything else in them to point me in the right direction. That table twelve is a flotronic 2, but an updated version and the subfunctions are in a different order. Have you got a link to download full manual as can not find this one on the eto site.
Thanks for your reply as well Gibbo, I was checking the main sensors today and they seemed to be within range, Just wish ther was a list that explained what inputs can hold off CCN Command. The clients are looking to replace this year anyway, but this has been a personal niggle of mine, and I like to fully understand these things. I have increased my knowledge anyway the amount I have gone through the manual. Oh I am in the london/Kent area. Also wish carrier had a tech line, that would be nice. If you think of anything else let me know. Thanks again

[Grizzly]

I will have a look and see what I can find.
Grizzly

[troymedhurst]

Thanks hopefully return the favor one day.

[troymedhurst]

Thanks Grizzly, got the manual. Some nice bedtime reading!
Thanks again

[Gibbo]

The only inputs too hold off FSM control are main water sensors connected to FSM, The CCN -On- Off switch and the 24 volt enable signal. However as i said there are also various items within the FSM Software that will stop it working but a laptop is needed.
You need the Flotronic 2 Phase 3 Controls book which is on the ETO website try looking under Model No 30GH260 The controls manual covers all Flotronic Chillers no matter what model no.

[troymedhurst]

Thanks Gibbo I will have a read through. I am back there next week I will kepp you updated.