PDA

View Full Version : Carel EVD EVO + ALCO EX6 valve - can it be bi-flow?



ballsofsteel
17-11-2018, 02:04 PM
Very simple question, very tough answer to find.

- A chiller with ALCO EX bi-flow valves.
- The EEV (Electronic Expansion Valve) will have to be replaced with Carel EVD Evo.
- The EVD Evo can drive the ALCO EX6 in theory and practice.... but....

Can the Carel EVD EVO also drive the bi-flow valves by ALCO?

Thanks.

Ps.: I spent more hours on this that I would like to admit.

Brian_UK
17-11-2018, 11:38 PM
Download this EXD-EVO document https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://www.carel.com/documents/10191/0/%2B0300006EN/6bd676be-922f-4fab-810b-2cf59f338c57%3Fversion%3D1.3&ved=2ahUKEwja_9CSy9zeAhWNHsAKHQ-tDdIQFjAAegQIBBAB&usg=AOvVaw0tRwth7tG5C7b6JSBNc7lG

Go to page 13 diagram 2.12 and look to the right, you will see the ALCO EX.. wiring schedule.

ballsofsteel
18-11-2018, 08:41 AM
Thanks Brian! This is how we wired it up. I mean Carel even displays the colors and the wiring on the EVD EVO display. I was just wondering if the ALCO bi-flow valve can be controlled with the EVD EVO UNI at all.

Ie.: There is uniflow and biflow.. and we have not been able to tell if we can drive a biflow model as well, or we have to replace the valve, or...
I'll try calling CAREL on Monday and post results, but it's a bit hard to like spell out the model and all with the Italian headquarters. "European English" calls are always tough. ;)

HVACRsaurus
18-11-2018, 09:34 AM
Good document Brian,

An interesting observation - I’ve opened this document in a .pdf reader where I can use a keyword search, the word “Alco” returns 25 matches throughout..

Numerous entries relate to “Alco” parameter / configuration

EVD EVO has quite a broad application

Glenn Moore
19-11-2018, 12:20 AM
In theory any stepper drive controller can drive a bi-flow valve or a uni- flow valve . The problem comes with the type of drive from the controller to the valve. From experience with Danfoss , Carel, Emerson , the problem comes where there is incompatibility between the controller and the valve when different manufacturers are involved . Often the problem is the power from the controller is not sufficient to drive the valve to keep the superheat under control. Often stepper valves are used on multiple compressor circuits with Scroll compressors. The mismatch between the valve and controller often leads to the suction superheat rapidly rising causing extremely high discharge temperatures and resultant damaged compressors due to the valve not responding to the signals coming from the controller. Most controllers have in the background parameters to change the current output to match the requirements of the connected valve. Therefore it is expediant to fit a controller and valve from the same manufacturer as the power settings are factory matched where dissimilar controller and valve can experience major control problems and then you have the problem which part is causing the fault the controller or the valve. So who do you call ??????.