Leak-rate calculator

Public calculation or owner-linked service record.

Use the public calculator for a quick leak-rate check. Use a 48-hour owner service link when technician service details should be recorded under a site, asset, or circuit.

HVACAudit by Subpart helps owners manage Subpart C refrigerant records for covered circuits. Subpart provides accounts, service links, reports, billing, and compliance history.

48-hour service linksOwners send a temporary link to the technician.
No technician accountThe technician can complete the service record without logging in.
Certification numberCertification number and service notes are captured with the record.
Owner historyCompleted records stay connected to the owner’s site, asset, and covered circuit.
Calculator access

Use guest access for quick checks or service links for owner records.

Public calculator users enter the required values manually. Owner service links use the owner’s asset and circuit history, so the technician records refrigerant added, certification number, and service notes.

Guest access Quick check

Use the public calculator when no account history is needed.

  • No account required.
  • Useful for immediate thresholding.

Owner service link Account history

Use a 48-hour service link when a technician needs to record refrigerant service details for an owner.

  • Technician account is not required.
  • Certification number and service notes are captured.
  • Subpart calculates the leak-rate result and adds the completed record to the owner account.
Methods

Annualizing and rolling average.

Use the method that fits the service event and available records.

Annualizing

Uses refrigerant added and time since the last refrigerant addition.

Rolling average

Uses refrigerant added during the selected 365-day period.

Record detail

Keep method and result together for later review.

Thresholds

Leak-rate thresholds by category.

Use the threshold that matches the covered appliance category.

40 CFR 84.106 threshold summary
Appliance categoryThresholdUse
Comfort cooling, refrigerated transport, and other covered appliances10%Use for covered appliances outside the commercial refrigeration and industrial process refrigeration categories.
Commercial refrigeration appliances20%Use for covered commercial refrigeration appliances.
Industrial process refrigeration appliances30%Use for covered industrial process refrigeration appliances.
FAQ

Common questions

Short answers for coverage, service links, calculation, and account history.

When should I use guest calculator access?

Use guest access for a quick leak-rate check when no account history is needed.

When should I use a service link?

Use a service link when the technician’s completed service record should be recorded under the owner’s site, asset, or circuit.

What threshold should I use?

Use the threshold for the appliance category.

References

Primary references

Use current rule text and EPA materials for compliance decisions.

Support

Subpart support

Questions about accounts, billing, service links, or calculator access?