Contact Supply & Return

Corrections, questions and ideas for new HVAC calculators are welcome. Email logan.luo@adsnova.cn; we usually reply within a few working days.

Reporting a Calculation Problem

To help us check a result quickly, please include:

• The calculator and every value you entered, with units
• Where the inputs came from, such as a data plate, a blower door test or a drawing
• The result you expected and its source, such as a manufacturer's table, Manual J report or ductulator
• Your location or climate zone, if the question involves design temperatures

Suggesting a Calculator

We are considering tools for refrigerant superheat and subcooling targets, static pressure budgets, heat pump balance points and dehumidifier sizing. Tell us which you would use and how you work it out today.

What We Cannot Help With

We cannot diagnose a specific system remotely, recommend a contractor or a brand, approve a design for a permit, or advise on gas, electrical or refrigerant repairs, which must be carried out by licensed professionals. If you smell gas or suspect carbon monoxide, leave the building and call your gas utility or emergency services first.

For Trainers and Schools

Instructors are welcome to use the calculators in HVAC courses. If a worked example or an extra output would help your students, such as metric units or a step-by-step breakdown, tell us what you teach.

Accessibility

If a calculator is hard to use on a phone on a job site, with a keyboard or with a screen reader, tell us the page and device; we treat these as bugs.

Response Times

We aim to reply within five working days and prioritise reports of a wrong calculated result.

Privacy and Copyright

See the Privacy Policy and DMCA Policy. Please put "Privacy" or "Copyright" in the subject line.