National Electric MFGTemporary power • HVAC load tools
Methodology

Electrical calculator · dew point / condensation / humidity

Dew Point & Condensation Risk Calculator

Calculate dew point and cold-surface condensation risk, then decide whether heat, dehumidification or airflow is the first lever.

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For workshops, plant rooms, stores, cold walls, metal roofs and drying jobs.

Field notes

Field notes for Dew point risk

Practical checks to run before this calculator result turns into a site decision.

Site check

Power, water and airflow have to work together

A dehumidifier plan fails if condensate, air circulation or supply capacity is ignored. Check the electrical plan alongside the drying layout.

Site check

Expect changing conditions

Early-stage flood drying can look very different from late-stage drying. Revisit the calculation after the first site readings rather than locking the initial setup in place.

Site check

Protect equipment from nuisance trips

Wet leads, pumps, compressors and stacked kit can create leakage or start-current problems. Split circuits before the job becomes intermittent.

FAQ

Dew point risk FAQ

Short answers written for UK temporary electrical and HVAC planning work.

What is the Dew point risk used for?

Calculate dew point and cold-surface condensation risk, then decide whether heat, dehumidification or airflow is the first lever. It is mainly for temporary HVAC, drying, cooling and site-power planning, especially where a quick pre-check is needed before selecting equipment or changing a temporary setup.

Can this replace BS 7671 design, inspection or testing?

No. It is a competent-person planning aid only. Final decisions still need current BS 7671 requirements, manufacturer data, inspection, testing, risk assessment and the actual site conditions.

What should I verify before acting on the result?

Check room volume, temperature, humidity, condensate handling, air movement, available supply capacity and whether wet leads or RCD nuisance trips are likely. If any assumption is uncertain, use the result as a prompt to investigate rather than as permission to energise.

What does an amber or red result usually mean?

It normally means the margin is weak, an assumption is missing, or the load should be split, staged, moved closer to the supply, reduced or reviewed by a competent electrician before use.

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