Hot Side

Flow Rate

lb/hr

Inlet Temperature

°F

Outlet Temperature

°F

Specific Heat (Cp)

BTU/lb·°F

Water ≈ 1.0, Light oil ≈ 0.5, Gas ≈ 0.25

Cold Side

Flow Rate

lb/hr

Inlet Temperature

°F

Outlet Temperature

°F

Specific Heat (Cp)

BTU/lb·°F

Design Parameters

Overall U (Clean)

BTU/hr·ft²·°F

Water-water: 150–250, Oil-oil: 40–60, Gas-gas: 10–30

Flow Configuration Multi-pass requires F correction

Total Fouling Factor

hr·ft²·°F/BTU

Typical: 0.001–0.003 for water, 0.002–0.005 for oil

Typical Overall U Values (BTU/hr·ft²·°F)

Service	Clean	Design (w/Fouling)
Water to water	200–250	150–200
Water to light oil	80–120	60–90
Oil to oil	60–90	40–60
Gas to gas	10–30	8–25
Condensing steam	400–600	300–500

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Results

Heat Duty

MMBtu/hr

Temperature Analysis

LMTD (Counterflow) -

F Factor -

Corrected ΔTm -

Min Approach -

Sizing Results

Required Area -

Effectiveness (ε) -

NTU -

U Design -

Heat Balance Check

Q (Hot Side) -

Q (Cold Side) -

Design Guidelines

F Factor: Aim for F ≥ 0.75. Below 0.75 indicates temperature cross - add shell passes or use true counterflow.

Approach Temp: Minimum 10–20°F typical. Closer approach = larger area = higher cost.

Fouling: Per TEMA, add 10–20% oversurface to maintain duty as fouling accumulates.

Heat Exchanger Calculator

Hot Side

Cold Side

Design Parameters

Typical Overall U Values (BTU/hr·ft²·°F)

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Results

Temperature Analysis

Sizing Results

Heat Balance Check

Design Guidelines

Related Calculators

Heat Transfer

Thermal Expansion

Temperature Drop

Gas Density

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