Hot Liquor Tank

STEP 5: Add a water output tee connection for the temperature probe

As the water exits the HLT out the ball valve at the bottom, a probe continuously sends a water temperature reading back to our control panel. The control panel then fires the heating element as required to maintain the exact water temperature we set.

In process control systems such as ours that involve fluid recirculating, temperature monitoring is usually done in the plumbing instead of in the kettle. This helps avoid temperature misreads due to stratification (layering).

The temperature probe we use comes with a cable that disconnects from the probe, making cleaning of the kettle much easier.

We use an RTD (resistive thermal device) temperature probe. Thermocouple based temperature probes are also readily available and are often used in brewing setups. While either will work, an RTD will typically be more accurate and remain more accurate (offer better linearity) over the brewing temperature range we use. RTDs also remain more accurate over time (less drift which means less re-calibration). The cost difference between the two is negligible in our setup.

Our last step is to install a tee connection to make room for this temperature probe as well as a quick disconnect so that hoses may be attached.

Breakdown of the water output tee connection parts:

(A) Stainless steel nipple threaded 1/2" x close NPT
(B) Stainless steel tee 1/2" NPT female
(C) Stainless steel male quick disconnect 1/2" NPT male
(D) Stainless steel bushing (reducer) 1/2" NPT male x 1/4" NPT female*

*Only required if a temperature probe with 1/4" NPT thread is used. If the recommended probe with 1/2" NPT thread is used, no bushing is required.

 

Wrap all of the threaded ends with PTFE white teflon thread sealant tape to ensure a tight, leak-free fit. Tighten using wrenches until the whole assembly is firmly attached to the kettle ball valve. Two wrenches are required: One to hold the ball valve steady to avoid it turning, the other to tighten the parts we're attaching.

There you have it!  Your HLT is done!

Continue on to Building Your Brewery - Mash/Lauter Tun.