Erratic Temperature Display

brewpilot · Joined: 16 Mar 2017 Posts: 11

During my last few brews I noticed that when I was changing the set temp on the HLT PID that I suddenly had erratic temperatures displayed as the HLT current temp. It would rise up to 300+ and then would slowly work its way back to near the actual value as indicated with a thermometer. It has made it very difficult to brew. If I turn the entire system off and then back on it seemed to reset itself.

We had a pretty good thunderstorm during a brew session that caused the power to turn off and on a few times. Could that have damaged the PID? Should I just replace that PID?

thanks,

**kal** · Posted: Sat Sep 23, 2017 2:51 am Post subject:

I could be a bad connection somewhere. It may be in the PID, but could be elsewhere, so you need to isolate where the issue is.

If a PID is displaying 'orAL' or the temperature's jumping around wildly then the PID is unable to communicate with the temperature probe tip.
The connection point between the temp probe cable and the stainless temp probe tip is likely damaged. It may be damage on either side or both sides.

One way this can happen if one is not careful when disconnecting/reconnecting the cable and the connectors are twisted and or turned when connecting them instead of lining up the tabs and pushing them together straight. There’s a little tab you need to line up when you mate the two halves together. To connect/disconnect, the tabs need to be lined up and pushed together, they should NEVER BE TWISTED/TURNED. If you twist/turn them to make a connection you may damage one or both ends. Twisting/turning can pull apart the wires inside the connector.

You can test if it's the cable only end by swapping cables with one of the known working temperature probes.
If swapping cables does not help I would recommend replacing the entire assembly (probe tip and cable).

Replacement cables as well as replacement cables with probe tips are available for order here:

http://www.theelectricbrewery.com/custom-temperature-probes

If twisting/turning caused damage and you are handy with a soldering iron, you may be able to easily repair the probe yourself. Remove the four small screws from the back of the probe and slide the resistor and cable end out of the probe (you should not have to remove it from the pot or Tee). You will see one end of the resistor soldered to pin #2, and the other side soldered to either 1 or 3 with a jumper between the two. One of those points is most likely broken and/or making intermittent contact. A quick re-soldering is all that is needed.

It could also be right in the PID, but that's less likely.

Kal

brewpilot · Joined: 16 Mar 2017 Posts: 11

Kal, I ended up rerouting the temp probe line and power plug to the boil pot inputs. After reconfiguring the boil pot to a HLT everything worked as advertised. A new PID arrives Monday. Thanks for making this set up available on line. I have been using it for over a year and really enjoy it.

**kal** · Posted: Sat Sep 23, 2017 10:56 pm Post subject:

Good stuff! Glad you figured it out!

Kal