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chillyblue
02-05-2011, 09:34 AM
Hi

I'm having a problem with this water chiller EF Type WKL430S3.2
All the condenser air inlet filters and condenser coils are clean, the condenser fans are working and are controlled via a fan speed controller, but it seems the fans reach high speed to late or to slow and the unit sometimes trips on high discharge pressure(normal after i've left site, not when i'm there:confused:).
Hi

I'm having a problem with this water chiller EF Type WKL430S3.2
All the condenser air inlet filters and condenser coils are clean, the condenser fans are working and are controlled via a fan speed controller, but it seems the fans reach high speed to late and the unit sometimes trips on high discharge pressure.
When the unit first starts the condensing temperature can easily reach 50deg C as the fans ramp up from low through to high speed, once the fans are at high speed the condensing temperature rapidly drops down to 30deg C. And then varying the condenser fans speed, maintain about 40 Deg C but on occasions the fans ramp up to late\slowly and the condensing temp exceeds it's safety and the unit cuts out.

Has any body got any factory settings\manuals so i can access\check the controllers settings as there are none on-site

Many thanks

C.B.

Tradewinds
02-05-2011, 10:12 AM
Hi CB,
I found this in google

Try these guys: (http://www.efcooling.com/images/stories/Produkte/pdf/GB/produkt_en.pdf)
http://www.efcooling.com

Basic product info, but probably not much good.
http://www.efcooling.com/images/stories/Produkte/pdf/GB/produkt_en.pdf


Just out of curiousity, is there any chance you could have air/non-condensibles in the system.

If you do a quick NC Test, you should find out if that is the problem. Otherwise, yeah contact the manufacturer about the settings etc.

Are the compressors fully loaded when it first starts? or is there some type of control to vary the speed or loading of the compressor on startup?

chillyblue
02-05-2011, 03:56 PM
Thanks tradewinds.
Not sure about the NC's, how would you go about quickly testing for NC's??
There's only one comp and no capacity control.

Tradewinds
02-05-2011, 04:46 PM
To test for non-condensables in the system, do the following:

Put your high side gauge onto the system (either discharge or liquid) liquid line is probably better but it doesnt really matter. Then switch the compressor off but try to leave the condenser fan running. This will help to remove any heat out of the refrigerant first. Leave the system off for about 20-30minutes. Basically, you are trying to get to a point where the refrigerant is the same as the ambient temperature. After about 10-20 minutes you can turn the fans off.

Next - Lets say you have R407C in the system and the ambient temperature is 20'C

If you look at your comparator you will see that R407C at 20'C is 9.38Bar. If you were to put your gauge on the cylinder of R407c, thats the pressure you would get.

So, you should there fore get the same pressure in your system when it is off and all the heat is removed from the refrigerant.
However, if you find that your pressure in the system is much higher than 9.38Bar, then chances are you have air or nitrogen in the system. If this is the case, then you will need to put new refrigerant in the system.

Hope that helps.

Stuart.

chillyblue
03-05-2011, 08:21 PM
Cheers

CB

1torr
11-05-2011, 02:44 PM
Hi. Ive had to adjust the PID control for the fans on these chillers in the past. Has it a Carel PGD controller? I may still have the settings somewhere. Cheers