Thermist develops productivity tools for MEP engineers and contractors, with a focus on automating repetitive Revit tasks. Thermist Revit addin streamlines mechanical piping workflows, helping engineers and designers work more efficiently while maintaining high quality standards. We also provide free web-based HVAC calculation tools, with equations and data sourced from ASHRAE and NIST. These calculators offer quick, accurate results for common sizing tasks. Our mission is to help MEP professionals work faster and smarter by automating routine tasks while maintaining full control over design decisions.
The Coil Connect tool, part of the Thermist Revit Add-in, automates branch piping connections from coils to nearby mains. The tool uses intelligent routing to create clash-free connections, supports customizable valve configurations, and works with both standard Revit families and fabrication parts. This automation dramatically reduces the time needed for routine piping tasks while maintaining design quality.
Similar to a manual spinning "ductulator", this ductwork sizing tool solves for pressure drop, velocity, and/or duct size based on user inputs. By default, the calculator works with round sizes unless a rectangular dimension is inputted. Rectangular ductwork utilizes the equation credited to Heubscher to determine equivalent round ductwork size for pressure drop calculations, per ASHRAE fundamentals Duct Design chapter. Flat oval ductwork utilizes the equation credited to Heyt and Diaz to determine equivalent round ductwork size for pressure drop calculations, per ASHRAE fundamentals Duct Design chapter. For all duct shapes, velocity is calculated based on the actual duct free area.
Advanced setting enables the flat oval ductwork sizing plus gives the option for custom inputs for material roughness, elevation, and temperature. Elevation and temperature are used to determine viscosity and air density using ISO 2533:1975, the ideal gas law, and the 1985 NIST journal regarding properties of air. Viscosity and air density are used in pressure drop calculations. When sizing rectangular or flat oval ductwork, the + button can be clicked to view additional sizes meeting inputted criteria. If only size is inputted, alt size areas and equivalent round dimensions meet or exceed inputted size.
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This pipe sizing tool is for HVAC non-gravity hydronic system sizing. Density and viscosity of water is interpolated based on NIST sourced data. Density and viscosity of glycol mixtures are interpolated based on Dow Chemical's DOWFROST/DOWTHERM data, which are referenced in ASHRAE Fundamentals. Advanced setting allows factoring in glycol plus gives the option for custom inputs for material roughness and fluid temperature. Internal pipe diameter assumes copper type L (per ASTM B88) for pipes NPS 2 or smaller and schedule 40 steel (per ANSI B36.10) for pipes NPS 2-1/2 and larger.
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This pipe sizing tool is for HVAC saturated steam system sizing. Sizing is applicable wher condensate does not hnhibit flow of steam. Density and viscosity of steam is interpolated based on NIST sourced data. Advanced setting allows custom material roughness input. Internal pipe diameter assumes schedule 40 steel (per ANSI B36.10) for all pipe sizes.
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Coil Connect Tool is provided as a routing assistance tool to expedite modeling processes in Autodesk Revit. The user remains fully responsible for verifying and approving all routing decisions as if they had modeled each segment individually. Each time the Software is used, the user must visually confirm the piping layout for accuracy and compliance with applicable standards and requirements.
The software is provided "as is", without warranty of any kind, express or implied, including but not limited to the warranties of merchantability, fitness for a particular purpose, and noninfringement. In no event shall the authors or copyright holders be liable for any claim, damages or other liability, whether in an action of contract, tort or otherwise, arising from, out of or in connection with the software or the use or other dealings in the software.
The user acknowledges that the Software does not replace professional judgment and that all design decisions remain the responsibility of the user.
Thermist Calculation software is provided "as is" and is to be used only as a reference. While we endeavor to provide accurate calculations, we make no warranties or representations of any kind concerning the accuracy, reliability, suitability, or completeness of any of the contents or data provided. Users are advised to always cross-check results against other sources or calculations, understand and verify all input data before using it in any critical applications, and recognize that the performance of the software might vary based on various factors.
