ThePitot

Field tools for TAB techs

ThePitot is training and job-site calculators from United Test & Balance. The traverse, outside air, RVA, grille balancing, sheave, coil face velocity and kitchen hood calculators are live. Courses for new techs are in progress.

Open the traverse calculator

Reference and training

Formulas

The formulas our calculators use, grouped by topic, with when to use each and a link to its calculator.

See the formulas

Quick conversions

Quick field numbers: PSI to feet of head for water and glycol, and tons to GPM for evaporators and condensers.

Convert

Specific gravity

Ethylene or propylene glycol, concentration, and temperature give the specific gravity and the feet of head per PSI.

Find SG

Training

Onboarding and exam-prep courses for new techs are coming soon.

Training

Calculators

Traverse calculator

Equal-area marks to the nearest 1/8 inch for round or rectangular duct (Log-T option on rectangular), with lining, average velocity, CFM, and a printable sheet.

Start a traverse

Outside air calculator

Enter the design OA and supply CFM, then get %OA and OA CFM by our static pressure method or by outdoor, return, and mixed air temperatures.

Check outside air

RVA grille calculator

Get a field Ak from CFM, FPM, and open area for one grille, or from a unit traverse and RVA readings on up to 12 grilles, with CFM for each.

Read a grille

Grille balancing

Enter design CFM and RVA (Ak × FPM) or capture hood readings for up to 24 grilles to get prelim and final CFM, % of design, and totals on a printable sheet.

Balance grilles

Sheave calculator

Enter design and actual CFM, RPMs, amps, sheaves, CD, and belt to get the desired fan RPM, an amp check against the tag, and a mid-range motor or fan sheave and belt from our charts.

Size a sheave

Coil face velocity

Follow the steps to turn Velocity Grid readings on a coil into airflow, % of design, and a target discharge static.

Check a coil

Kitchen hood

Pick Greenheck / Accurex, CaptiveAire or Halton and the filter type, enter your readings, and get exhaust and make-up air CFM, % of design, pass/fail and the balance on a printable sheet.

Test a hood

Affinity laws

Fan and pump laws: pick what you're changing (speed, flow, pressure or head, BHP, sheave, or impeller trim), enter the current readings, and get the new values with a motor HP check.

Run the fan and pump laws