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alpha
12-03-2007, 11:22 AM
Hi, wonder if anyone could give a little info on electronic expansion valves.

What I have to do is build a unit from scratch, one compressor and two evaporator and would very much like to incorporate a pair of EEV.
I been looking at danfoss system and have come to the conclusion that two akv10-1 and akc115a controller may just meet my needs.

So saying that, what is the Danfoss setup like? reliable? easy to setup etc?? good points, bad points.....

Also, I see Alco produce an eev system, anyinfo on Alco product?

So many questions too little time :D
Thanks in advance for any help :)

750 Valve
12-03-2007, 12:53 PM
On a single liquid line feed the pulsing of the akv's can cause liquid hammer and hard to stabilise sst - better off on a large header fed system with multiple evaps. For a single system step motor valves provide much better operation and are availabe for use with a small danfoss ekc controller, carel do them too. Hope this helps.

Pooh
12-03-2007, 05:37 PM
Setup on the AKC controllers is a bit of a pain using the hand controller and can take a while to get the hang of. The Alco system with the stepper motor valves is more suitable for multiple evaporators as 750 Valve says that the AKV's tend to cause hammer in the liquid line which I have never managed to solve.

Ian

NoNickName
12-03-2007, 06:16 PM
My favourite is Polycool from siemens.
https://www.hqs.sbt.siemens.com/oem/e/oem_ref_dow.asp

Mark
12-03-2007, 07:01 PM
Hi, wonder if anyone could give a little info on electronic expansion valves.

What I have to do is build a unit from scratch, one compressor and two evaporator and would very much like to incorporate a pair of EEV.
I been looking at danfoss system and have come to the conclusion that two akv10-1 and akc115a controller may just meet my needs.

So saying that, what is the Danfoss setup like? reliable? easy to setup etc?? good points, bad points.....

Also, I see Alco produce an eev system, anyinfo on Alco product?

So many questions too little time :D
Thanks in advance for any help :)

alpha

The merits of EEVs in this application would be limited.
If the system is not designed 100% correctly, it would have problems as mentioned previously.

Regards

Mark

Andy
12-03-2007, 10:35 PM
Setup on the AKC controllers is a bit of a pain using the hand controller and can take a while to get the hang of. The Alco system with the stepper motor valves is more suitable for multiple evaporators as 750 Valve says that the AKV's tend to cause hammer in the liquid line which I have never managed to solve.

Ian

Hi Guys:)

we would fit danfoss on such an application. It would take me a matter of minutes to set up the AKC 115 controller.

Having saidthat think about using a AK2 CC controller, this will eventually superceed the AK range.This type of controller in a bit like a PLC with inputs and outputs. You use a program called service tool set the contoller up once, then use a sofware download to each subsequent controller, it takes about 2 minutes to download an AK2 CC program once you have pre written the program for your set up.

As for the valve pulsing effecting the liquid line and supply of liuid to the valve that is all down to the correct sizing of the liquid line, the correct velocity chosen and the amount of available subcool.

In my experience pulse width valves are less troublesome than stepper motors that require battery drivers to shut them during a power failure. I have seen a few 100hp compressors burnt out due to the Carel version of the stepper motors on chillers manufactured in the UK (The Alco valve is a badged carel)

Danfoss also produce an EKC 414 single evaporator controller, which is able to be set up from a dispaly (two needed in this case) no handheld and probably only a dozen parameters to set up.

Danfoss also have a stepper motor expansion valve available, but only in large sizes, they can use the carel valve on some on there din mounted EKC range, (EKC 316 I think) if you want to go this route.

We use Danfoss, I know Danfoss, the engineers know Danfoss, they have a large range and the product back up and relyability. I advise Danfoss:D

Kind Regards Andy:)

scruffy
13-03-2007, 01:30 PM
Hello,
I have had the experience of setting up EEV's on a similar system myself. I found using EEV's on a small system like this pointless. The controllers are not perfect. One evap may achieve its superheat and close the valve down. The suction pressure then drops and the superheat for the other evaporator then increases dramaticly and the valve opens. The other valve then re-opens, the valve that has opened up to compensate for the low suction pressure then doesn't close down fast enough and then the issue of floodback arrises. This valve with low superheat then closes down and the process starts over again. The best RMD for this system would be a simple TX valve. It would be cheaper, easier to install, more reliable and probably better on the warranty account. The only time i have seen an EEV work without causing trouble is on a system with 10 or more evaporators. If the customer wants the fridges to alarm on hi temp sell them a simple M2 alarm system from danfoss. Or even cheaper wire 2 revers acting thermostats in paralell with a buzzer.

NoNickName
13-03-2007, 03:46 PM
For those like me with faithfulness in big manufacturers, like Siemens, here's an email just smoking in my mailbox (email addresses covered to protect the innocents). The argument here is CPS40 new EEV regulator and controller.

***** wrote:
> Dear *****,
>
>
> Regarding our alarm problem:
> The alarming logic is wrong implemented.
> We have to adapt the software. I will inform you as soon as I have the new version.
>
> Best regards,
> *****

alpha
13-03-2007, 07:50 PM
Hi, thanks for the feedback all, much appreciated and of much help :)

So you now got me thinking, should I really stick with what I know?, TEV.
Yeah but no but.... I really want to play with EEV. :D
The whole project (not intended for a customer but for my own use) is going to be used in electronics cooling, one evap for direct surface mount spot cooling and the other for ambient air, that's about all I can say for now on that unfortunately, apart from the heat loads will pretty much be non fluctuating, a consistent level load.

Having said that, a TEV is kind of not favourable in this application because if I need to tweek superheat it's going to be a bit of a pain, switch off electronics, remove lid, tweak screw refit and try again, I do hope that EEV would allow me to tweak superheat to some degree on the fly as if to say..

*back into deep thought mode.

dai kin
13-03-2007, 09:45 PM
When we are on the subject of eev`s,i have two new denco units with carel eev`s on them and i am having murder try to set the superheat(denco no help)anyone else worked on these?Everything else is ok (head,liquid,sub cooling)just s/h

Andy
13-03-2007, 10:28 PM
When we are on the subject of eev`s,i have two new denco units with carel eev`s on them and i am having murder try to set the superheat(denco no help)anyone else worked on these?Everything else is ok (head,liquid,sub cooling)just s/h

Superheat toolow or too high:eek:

Kind Regards Andy:)

dai kin
16-03-2007, 04:53 PM
Too high,but i think it is slightly short of r407c.Going back on monday when all the equipment is going on,so i will have some heat load and will be able to check it properly.(I have spent the last four years on vrv install and forgot all my fridge know-how)

Mark
16-03-2007, 05:00 PM
Hi Guys:)

we would fit danfoss on such an application. It would take me a matter of minutes to set up the AKC 115 controller.

Having saidthat think about using a AK2 CC controller, this will eventually superceed the AK range.This type of controller in a bit like a PLC with inputs and outputs. You use a program called service tool set the contoller up once, then use a sofware download to each subsequent controller, it takes about 2 minutes to download an AK2 CC program once you have pre written the program for your set up.

As for the valve pulsing effecting the liquid line and supply of liuid to the valve that is all down to the correct sizing of the liquid line, the correct velocity chosen and the amount of available subcool.

In my experience pulse width valves are less troublesome than stepper motors that require battery drivers to shut them during a power failure. I have seen a few 100hp compressors burnt out due to the Carel version of the stepper motors on chillers manufactured in the UK (The Alco valve is a badged carel)

Danfoss also produce an EKC 414 single evaporator controller, which is able to be set up from a dispaly (two needed in this case) no handheld and probably only a dozen parameters to set up.

Danfoss also have a stepper motor expansion valve available, but only in large sizes, they can use the carel valve on some on there din mounted EKC range, (EKC 316 I think) if you want to go this route.

We use Danfoss, I know Danfoss, the engineers know Danfoss, they have a large range and the product back up and relyability. I advise Danfoss:D

Kind Regards Andy:)

New job Andy:)

NoNickName
16-03-2007, 05:09 PM
In my experience pulse width valves are less troublesome than stepper motors that require battery drivers to shut them during a power failure.

That's how Carel is doing things. :eek::D
Siemens stepper motor controlled valves have a return spring.

Andy
17-03-2007, 09:54 AM
That's how Carel is doing things. :eek::D
Siemens stepper motor controlled valves have a return spring.

Hi NoNickName:)

didn't know that, but it might explain why the airedale chillers have nice shinny stainless expansion valves on the newer models and they say the expansion valve problem has been fixed:eek: (must be a siemens valves with airedales name on it).

Kind Regards Andy:)

Andy
17-03-2007, 09:58 AM
New job Andy:)

:D :D
no I don't work for Danfoss, but I do like there electronic controllers and their inverter drives:)
There industrial valves are over priced:( and they make a good maneurope pot compressor, but not really effecient enough for the market today

Kind Regards Andy:)

Andy P
17-03-2007, 11:03 AM
When we are on the subject of eev`s,i have two new denco units with carel eev`s on them and i am having murder try to set the superheat(denco no help)anyone else worked on these?Everything else is ok (head,liquid,sub cooling)just s/h

Which refrigerant? To glide or not to glide?

cheers

Andy P

Denco Technical
25-05-2011, 12:20 PM
When we are on the subject of eev`s,i have two new denco units with carel eev`s on them and i am having murder try to set the superheat(denco no help)anyone else worked on these?Everything else is ok (head,liquid,sub cooling)just s/h
Why do you want to set up the s/h ?? is the EEV set up correctly??

Is it a EEV1 or a EEV2 ... how old is the unit?


Talk to me and you may get the answer you are looking for.

Argus
25-05-2011, 12:40 PM
Talk to me and you may get the answer you are looking for.




.... er, this thread is some 4 years old, Rob!

He might have sorted it by now!


.

Denco Technical
03-06-2011, 10:23 AM
lets hope so eh !!

batulao
23-09-2011, 12:00 PM
The new Electronic Expansion Valve from Carel, called EVD EVO (for evolution) is pretty amazing in terms of simplicity of configurations and auto adaptability:
From a configuration point of view, you only need to setup 4 parameters (Refrigerat type, Valve size, Type of Sensors and Application on which the EEV is installed - Cabinet, cold room, chiller etc.). It's none!!!! The driver finds the most suitable parameters to operate with stability the system! This driver has also been enriched with ad Autotuning Algorithm which helps overcome any unbalanced system... Have a look at the video and datasheets at this link:
http://www.i-acs.co.uk/store/index.php/electronic-expansion-technology-eev/evd0000e50.html

NoNickName
25-09-2011, 01:18 PM
I would be quite careful before considering Carel. It's on a very steep downslope .