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kengineering
11-04-2014, 01:44 PM
Hi everyone, In my search for a Danfoss electronic expansion valve the Selection chart shows 2-possible choices. There is a heading stating "VALVE LOAD" . Under this heading for each is listed one with a rating of 78.1% the other choice 49%. I'm not sure I fully understand this aspect to make the correct choice. I have included a picture.
Thanks too all.

NewmanRef
11-04-2014, 05:22 PM
Select your valve to the correct capacity Kw as you would normally. I think the valve load is the expected percentage that valve will open to suit the given capacity. Depending on the control you are using the valve load/drive usually goes up and down to maintain a steady superheat.

RANGER1
11-04-2014, 10:12 PM
Hi everyone, In my search for a Danfoss electronic expansion valve the Selection chart shows 2-possible choices. There is a heading stating "VALVE LOAD" . Under this heading for each is listed one with a rating of 78.1% the other choice 49%. I'm not sure I fully understand this aspect to make the correct choice. I have included a picture.
Thanks too all.

Ken 49% one for sure, as it will control nicely as well as cope with varying & high load as well as possible lower pressure difference across valve.
They can can control down to 10%
Both will work, but 49% would be better.

Thats my opinion anyway

kengineering
14-04-2014, 07:03 PM
Ken 49% one for sure, as it will control nicely as well as cope with varying & high load as well as possible lower pressure difference across valve.
They can can control down to 10%
Both will work, but 49% would be better.

Thats my opinion anyway
Therefore when selecting this type of valve I should choose one thats close to mid point or 50% so it can accomodate the best of both above and below.
That does make sense. Now why couldn't Danfoss answer me so concisely.. Thanks.

RANGER1
15-04-2014, 05:10 AM
Ken,
You can also put in conditions your plant may run in Danfoss Directcalc.
This can show how valve reacts for your situations, which can also assist with the selection of orifice size.

kengineering
17-04-2014, 06:17 PM
Oh Ok Ranger, I just got a call from Danfoss tech support and they helped. Seems the selection calc I Dl from them was obsolete.

RANGER1
17-04-2014, 09:28 PM
Oh Ok Ranger, I just got a call from Danfoss tech support and they helped. Seems the selection calc I Dl from them was obsolete.

So Ken what is the outcome from their advice, anything different?

kengineering
05-05-2014, 08:26 PM
Sorry, It's been awhile but they suggested the Valve rated 49%. Hooked me up with some new literature. I'm just getting started in this case controller stuff. New DOE stuff has us lookin for ways to save kW's.

RANGER1
05-05-2014, 09:36 PM
Thanks for update