Mash-Tun Calibration
Determines your mash tun's heat retention characteristics for accurate strike temperature calculations.
How to Calibrate
Water Test Method
Heat Water to typical strike temperature
Add to Mash Tun without preheating
Monitor Temperature every 5 minutes for 60 minutes
Calculate Heat Loss - Tool provides correction factor
Actual Mash Method
Conduct Normal Mash with typical grain bill
Track Temperatures - Strike, actual mash, after 60 min
Input to Calculator - Get your heat capacity factor
Why Calibrate
Every mash tun loses heat differently based on:
Material: Plastic, stainless steel, copper
Insulation: Quality and thickness
Size: Surface area to volume ratio
Environment: Ambient temperature
Preheating: How well you preheat
Calibration gives you a "heat capacity factor" specific to your equipment.
Understanding the Results
Heat Capacity Factor
0.0: Perfectly preheated, no heat loss
0.1-0.2: Well insulated or preheated
0.2-0.3: Average homebrew setup
0.3-0.5: Poor insulation or cold tun
Using Your Factor
Input into strike temperature calculator
More accurate temperature predictions
Consistent mash temperatures
Better enzyme activity
Improving Heat Retention
Insulation Options
Reflective Bubble Wrap: Cheap, effective
Foam Board: Cut to fit
Sleeping Bag/Blankets: Simple solution
Spray Foam: Permanent option
Preheating Methods
Fill with hot water 10 min before
Rinse with boiling water
Heat with strike water overage
Store in warm location
Testing Variables
What Affects Calibration
Ambient Temperature: Test in brew conditions
Wind/Drafts: Increase heat loss
Lid Seal: Critical for retention
Mash Volume: Fuller tun retains better
When to Recalibrate
New equipment
Changed insulation
Different season/location
Inconsistent results
Practical Examples
Example 1: Cooler Mash Tun
38 liter (10 gallon) cooler
No preheating
21°C (70°F) ambient
Result: 0.25 factor
Example 2: Insulated Kettle
Stainless kettle
Wrapped insulation
Preheated
Result: 0.10 factor
Using Your Calibration
With Strike Calculator
Use your calculated heat capacity factor
More accurate temperature predictions
Reduces mash temperature misses
Recipe Planning
Account for your system's heat loss
Plan realistic step mash schedules
Calculate water additions accurately
Tips
Use consistent test methods
Calibrate thermometer first
Test in typical brewing conditions
Average multiple test results
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