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koolit5665
09-08-2012, 05:24 PM
Hi All,

Wonder if any of you have experienced anything similar to what we're having intermittent problems with (this has been from a couple of months after install around 2 years ago)...

One office has 2 x Roundflow Size 63 Cassettes operating as a twin off a Branch Box (from a 3 pipe VRV).

iTouch controller is set up to handle change over between heating/cooling as needed (i.e. Auto mode on BRC1D's not used).

Intermittently the units will not switch over from heating to cooling even though the set point is theoretically calling for it.. For example. Room temp is 28c (on return air temp sensor in cassettes). Setpoint of unit is 22c. BRC1D still shows 22 on the display (as you'd expect) but shows the heating symbol and doesnt switch over to cooling unless you manually change it to cooling mode on the iTouch or take it right down to 18c on the setpoint.

This only happens intermittently and is completely random. Once you switch it over manually to Cool mode the room comes down to temp within a few minutes.

Daikin have suggested double checking address settings and resetting the system which have been done numerous times but they now suggest a site visit to establish what's happening. The problem is that they can't come out for 2 weeks and this would leave the customers without cooling for 2 weeks - which isn't acceptable.

Have any of you guys/gals experienced the same thing and if so how did you solve it?

Cheers,

Rick.

The Viking
09-08-2012, 05:32 PM
Rick,

To answer your question, no I haven't.

But, if Daikin want 2 weeks to attend site now in the summer and everything...

Why not leave the units in cooling only mode until Daikin arrives???

:cool:

.

koolit5665
09-08-2012, 05:36 PM
Rick,

But, if Daikin want 2 weeks to attend site now in the summer and everything...

Why not leave the units in cooling only mode until Daikin arrives???

:cool:

.

That's the issue - it'll be ok now if we keep it in Cool mode so they won't be anything for them to find when they turn up and that'll be a £500 bill winging its way to me!

This only happens when the system needs to change over from heat to cool and then it only happens randomly! So they've said the only way they can diagnose is if the unit is left in 'fault' conditions for those 2 weeks (even though it doesn't show a fault!)

koolit5665
09-08-2012, 05:37 PM
Cheers for the suggestion by the way!

:D

frank
09-08-2012, 08:31 PM
It sounds like you may not have a 'Master' heat -cool changeover set on the 2 fancoils from the BS box.

When 2 fancoils are connected to the BS box, the changeover command can only come from one fancoil. Without a Master, the BS box just sits on the last command i.e., the one you manually entered. That is, until the iTouch times to it's next schedule, when everything reverts back.

Temporarily connect a spare BRC controller to one of the fancoils and see if the display is flashing....if it is, press the 'Mode' button to designate that fancoil as a Master.

After you disconnect the BRC you must power down the fan coil and re-power, to prevent a fault code....I usually just use the blue power connecter off the transformer on to the PCB

If it's happening randomly, I would also check that the F1 F2 wiring is complete, (no joints or star points), is at least 0.75mm2 and un-shielded, and is not 'thrown' across other electrical items (cables, lights, etc) that can cause interference..

koolit5665
10-08-2012, 01:37 PM
Hi Frank,

There's definitely a master set-up on that circuit as the iTouch prohibits any changes of temp to the Slave unit.

Daikin have just called me to say they had a cancellation for next Friday so hopefully we'll get to the bottom of it then..

Cheers,

Rick.

frank
10-08-2012, 05:29 PM
Rick

The programming on the iTouch won't show if the fan coil has lost it's designation. The only way to check is to connect a BRC controller to the fan coils as described.

Best of luck

cool#9
11-08-2012, 09:56 PM
Hi everyone
I think frank is right...
...try to fix code 22 from 9.01 to 9.02 with a BRC on master unit.
rgds
cool#9

AbsoluteWDJ
12-08-2012, 07:27 PM
Hi All,

Wonder if any of you have experienced anything similar to what we're having intermittent problems with (this has been from a couple of months after install around 2 years ago)...

One office has 2 x Roundflow Size 63 Cassettes operating as a twin off a Branch Box (from a 3 pipe VRV).

iTouch controller is set up to handle change over between heating/cooling as needed (i.e. Auto mode on BRC1D's not used).

Intermittently the units will not switch over from heating to cooling even though the set point is theoretically calling for it.. For example. Room temp is 28c (on return air temp sensor in cassettes). Setpoint of unit is 22c. BRC1D still shows 22 on the display (as you'd expect) but shows the heating symbol and doesnt switch over to cooling unless you manually change it to cooling mode on the iTouch or take it right down to 18c on the setpoint.

This only happens intermittently and is completely random. Once you switch it over manually to Cool mode the room comes down to temp within a few minutes.

Daikin have suggested double checking address settings and resetting the system which have been done numerous times but they now suggest a site visit to establish what's happening. The problem is that they can't come out for 2 weeks and this would leave the customers without cooling for 2 weeks - which isn't acceptable.

Have any of you guys/gals experienced the same thing and if so how did you solve it?

Cheers,

Rick.

Just a thought. Have the return air sensors been disabled (using remote control sensors only) but are still displaying on the Itouch control?

Mentallist
13-08-2012, 08:43 PM
Just a suggestion, but if you have lost the heat cool master, you can use the lock and release function on the ITC to re-select which unit you want as the master, you dont need to use code 22: 9-02 by doing it this way.

koolit5665
14-08-2012, 10:01 AM
Cheers for all the suggestions guys - we're not back on site until Friday with Daikin so will double check all the above then :-)