Posted Sun Jun 1, 2008, 2:43pm Subject: Temp Diffence at Group Head with PID
I think I have a pretty simple question - on my PID'd Silvia, what is the temp of the water at the group head when my PID is reading 225? Does the temp variation stay constant - that is, is the temp at the group head always 20 degrees cooler than the PID shows, as an example?
Posted Sun Jun 1, 2008, 3:47pm Subject: Re: Temp Diffence at Group Head with PID
Hi, Mitch,
I do not have the Auber PID from HiTech, but rather a Watlow PID from MLG. My machine might not translate the same as yours, then, because PID temps will vary depending on where HiTech placed the thermocouple on the boiler. MLG PID kits secure the thermocouple on the left-most screw on the top of the boiler when you are facing the machine. Any idea where your thermocouple is placed? Jim Gallt, who owns MLG, has said that with the thermocouple in this location, PID 226-229 will yield brew temp at approximately 201. But, even then, the brew temp will vary from machine to machine. So here's my first advice: experiment with different temps and follow your taste buds. What's really important is that you now have a repeatable starting temp at the boiler.
But, just to complicate matters, brew temp will also largely depend on the temperature your grouphead happens to be at the time. So, here's my further advice: Remember, the PID is only controlling temperature at the boiler. The group still needs to be handled to get repeatable results. So, get a consistent flushing routine down. Between shots, I flush just enough water to do the portafilter wiggle in the group and clean the group with a brush (ends up being the PID dropping around 18 degrees). Then I wait 3 minutes with the portafilter in the group, then I load the grounds, let excess steam out the wand (really helps prevent channeling), and pull the shot. If Silvia's been sitting idle for a while, I pull a couple of blank shots in this manner and then pull a real shot. Having a routine like this helps assure that the group doesn't get too hot or cold, making you scratch your head when you can't repeat your previous kicka$$ shot.
If you really want to monitor the temp at the group, you could install a grouphead thermocouple: Click Here (www.home-barista.com)
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
= No New Posts since last visit 