Help wanted with homemade auto draw off

[500592]

Hi I am looking to build an auto draw for next year but I want to know if that parts I have picked out will work before I buy them. For the PID controller I want to use this one http://www.auberins.com/index.php?main_page=product_info&cPath=1&products_id=14 with this temp probe http://www.auberins.com/index.php?main_page=product_info&cPath=20_15&products_id=46 and a 3/4 inch honeywell zone valve from a heat system it will be on a 3x8 raised flue evap no ro but eventually I would like to upgrade the valve but I can get this one for free:-D thanks for any help.

[RollinsOrchards]

At a quick glance:

The Controller: The accuracy is listed at 0.2%. That doesn't seem like much, but at 219 degrees, it seems like it could be off by half a degree. Of course I didn't look up what the accuracy of the professional units is. . .

Before buying you ought to ask the seller how fine the control settings are on the device. With the sensor you selected you can get temperature readings to the tenth of a degree, but ask if the controller is capable of turning a device on at 219.8 and turning it off at 219.5?

I can't quite visualize how to seal around the temp probe if it sticks through a port into the side of the pan. I suppose you could build a bracket to suspend it in the liquid.

The zone valve may work, but it could gum up as well. Figure out how to take it out and put in a ball valve if your system quits while boiling and you should be all set.

[twig113]

I am currently making one using a PID from LightObject, i am using this controler http://www.lightobject.com/0-999F-Fahrenheit-Temperature-Controller-P139.aspx it is accurate to .2% but it is for a heating unit, so to correct this then you can go into the settings and use the alarm function to switch on an off the valve. Another thing is that you can only adjust it to the nearest degree, but just add in a second valve so you can thin the syrup down when you get close to a full bucket. and just draw a bit thin. you can also get a thermalcouple from LightObject as well which you can find here http://www.lightobject.com/10ft-3M-K-type-Thermocouple-with-8cm-stainless-steel-pole-P491.aspx I hope this helped