Rhvac Buyer's Guide

Doing your own research before you purchase load calculation software can pay off big for you down the road. This is software that you will be relying on day in and day out, for hours at a time, so please do your homework before you buy. We encourage you to install and test the demo version of Rhvac as well as each of the demo versions of our competitors' software and compare them all side by side, feature for feature. Here's a list of things to look for:

Accuracy
Ease of Use
No Copy Protection
Graphical Input
Links to Other Software
Advanced Features

Accuracy: The 8th edition of ACCA’s Manual J hvac load calc procedures known as MJ8 is more sophisticated than the 7th edition and has introduced many new material types and calculation procedures. Make sure the software follows MJ8 and includes all four addenda, A-D. Additionally, look for software that can print results with intermediate load factors included instead of just printing the final results as a black box output. Elite Software’s Rhvac program meets all of these requirements.

Ease of Use: All software vendors claim their software is very easy to use. And a good salesman can make any program look easy to use as he whizzes through everything. But the true test is, can you make sense of it when you try running it by yourself? Always try running trial software yourself before making a purchase and check for the following:

• Does the software use standard windows data entry techniques? For example, if you have to press the "home" key before you can edit text in an input field then that is a non-standard technique that must be learned.

• How good is the built-in help? Do you get both an input explanation and choices with one mouse click or do you have to double click and maybe press a function key to get more information, often with no choices available?

• How are area inputs handled? Many load calc programs require you to do the math yourself to calculate areas for roofs, wall, and glass. The best programs allow you to enter lengths and widths of these items so that areas are automatically calculated.

• Manual or graphic data entry? The software should be just as easy to use in a manual input mode as it is when in a graphic input mode. For example, check whether a window can be assigned to the correct wall easily when in the manual input mode.

• Quick pick of recently selected items? Manual J provides hundreds of materials for floors, roofs, walls, glass and doors. Software that remembers your most recent selection and places it at the top of the list for the next use is easier to use than software that forces complete reselection.

• Built-in room names? Much of the typing required in most load calc programs is for the room names. The best software provides a quick pick list of all common room names so as to minimize the typing required.

• Important data visible? Many load components in a room such as roofs, walls, and glass have a number of key aspects about each component such as U-factor, SHGC, etc. Software that displays more of this information without requiring constant clicks and viewing numerous pop-up windows will be faster and easier to review and check.

• Save reminder? It’s no fun retyping lost data you forgot to save. The best software provides a pop-up save reminder that can be set for any time interval or turned completely off if desired.

No Copy Protection: Are there limits on how many computers on which the software can be installed? Do you have to contend with copy protection schemes to install the software on multiple computers? There are no copy protection hassles with Elite Software programs. Software vendors that use copy protection typically do not tell you about their copy protection scheme until after you have bought the software. Be sure to ask about copy protection before purchasing software!

Graphical Input: Good load calc software provides an easy manual data entry system with an optional graphic data entry system. The optional graphic data entry system should work with both commercial and residential load calc programs.

Links to Other Software: Good load calc software should include free built-in links to popular energy rating software. Check to see if the program links to all of these popular programs:

• REM/Rate: AEC Corp’s home energy rating software

• REScheck: U.S. government’s energy compliance program

• EnergyGauge USA: Florida Solar Energy Center's national energy rating program

• EnergyGauge FlaRes: Florida Solar Energy Center's program for Florida users

Advanced Features: The data entry and results from an hvac load calculation offers opportunities to do more than just calculate peak heating and cooling loads. Look for maximum value by choosing a load calc program that also includes these features:

• Selection of Equipment: You should be able to select air conditioners, furnaces and heat pumps from up to date equipment data built in to the program and downloadable from the internet.

• Sizing Ductwork: The program should give you multiple options on how to size and design your ductwork. Rhvac includes free built-in main trunk and runout sizing, and a free Duct Static Pressure Loss Calculator. When you purchase the Manual D Ductsize program you can design your entire duct system and get a complete pressure analysis.

• Printing Sales Proposals: The software should include options on generating your own printable sales proposals and other documents. Rhvac includes a free Custom Report window that lets you enter your own text into a report, and which includes several options on printing information about your heating and cooling systems. When you purchase the Proposal Maker program it will let you create fully customizable proposals, letters, and other documents that include graphs and live fields that link to the load calculation results.

• Loads at Four Levels: The best software calculates at four levels in one run: rooms, zones, systems, and total building.

• Project Explorer Tree: This window lets you do drag and drop zoning and manipulate the overall organization of a project in a graphic format. It also lets you copy and paste rooms and other data within your current project and from other projects.

• Advanced Copy and Paste : You should be able to cut, copy, and paste room data within a project and between other projects. The same goes for general project data and system data.

• Program Links: Data should be transferable to duct sizing (Manual D Ductsize) and energy analysis programs (Energy Audit).

• Report Customization: Color selection and fonts should be adjustable for all reports.

• Save Reports: Reports should be savable as a file so that they can be e-mailed, for example.

• Global Material Change: You should be able to make global changes at once within a project instead of having to revisit each room and change individual items.

• Rotate and Mirror Plan: You should be able to rotate and mirror one or more rooms in the building at once, and the program should provide a Building Rotation Report that shows you the loads and airflow requirements for each possible rotation.