Expansion Tank Calculator
Size expansion tanks for closed-loop hydronic heating and cooling systems.
Standard Tank Sizes
| Size (gal) | System Vol (gal) | Typical App |
|---|---|---|
| 2.1 | 20-50 | Residential |
| 4.4 | 50-100 | Small Commercial |
| 10.3 | 100-250 | Commercial |
| 20 | 250-500 | Large Commercial |
| 40 | 500-1000 | Industrial |
For 180F HW, 12 psi fill, 30 psi relief
Design Guidelines
Pre-Charge: Set 2-3 psi below fill pressure
Location: Pump suction side preferred
Glycol: Increases expansion by 10-20%
Safety: Size for 10% extra capacity minimum