Many apps for smartphones and tablets have become available for business use as these devices have become increasingly ubiquitous. The range of mobile applications is large and rapidly growing—and apps created for use in the HVAC, building energy performance and energy efficiency fields are no exception.
During the past year or so, Cx Associates staff have begun to informally field-test apps for a variety of uses related to our work and have found there to be a lot of exciting potential with what is available in the marketplace. In general, we’re using the apps for “back-of-the-envelope” style calculations in the field or for quick reference during desk-side analysis and not for critical and/or “final” calculations for our clients. While we believe most/all of the apps we’ve tested are accurate, because of the general lack of transparency down to the level of the detailed calculations, we don’t rely on them for core analysis work. Despite this caveat, we have found them very useful in day-to-day work and are excited about their potential to increase our effectiveness at saving energy for our clients.
So, when we talk about apps, what do we mean? Despite Apple’s attempt to defend their trademark of “app” as their own, it appears that they have failed and it has become the generic term for mobile applications. The two most common “app stores” for these mobile applications are Apple’s App Store for iOS and Google Play, which is the primary App Store for Android. This post focuses on applications generally available for one or both of these mobile platforms. There is some limited diversity in the brands of personal tech which Cx Associates staff use, but at present, the vast majority of users have an Apple device of one kind or another—either a iPhone or an iPad. As a result, this article leans more toward the selection of applications available for iOS devices though we have included links for Android when possible.
To support this blog post, an informal survey was conducted within our office to see what apps our engineers have been using — and which they found most useful. The responses are organized below by general type of application. This is by no means the definitive list of applications useful in the fields related to building energy performance and efficiency—and we would of course appreciate any additional suggestions for what others have found useful in the field, so please, let us know what apps you find useful by adding some comments at the end of this post!
There are some excellent application-specific reference guide apps available for different engineering disciplines and trade audiences. Our staff has found PDF reader/organization apps to be a more flexible solution to reference needs by utilizing the docs we already have stored in our office file server or personal machines. Examples given by our engineers included local region 8760 BIN-hour tables, motor FLA tables, VAV box sizing schedules, and other custom reference docs we have developed over the years. In addition to quick reference tables and guides, the PDF readers can even be used to carry complete sets of project documents including full drawings and spec sets. The graphics rendering of large project design drawing sets can be slow with some current hardware, but the convenience of having all the documents loaded onto an iPad in the field, for example, can be worth the occasional delay. If we plan to work closely with a set of drawings in the field, a hard copy or at least a full-size laptop interface can’t be beat. But in a pinch, being able to look up a specific spec section in a couple of minutes can be very helpful.
The following apps are what we’re using for PDF readers/file managers:
Good Reader Good.iWare Ltd. ($4.99)
A PDF reader with extensive file management and commenting functions. With a tablet device, drawings can be marked-up and commented in the field and later printed in full size.
Adobe Reader Adobe Systems Inc (Free)
Another well known PDF reader, less feature-packed than Goodreader, but free.
Probably the category that encompasses the majority of the apps we’ve been finding useful are some kind of calculation program, usually applications specific. Traditionally, HVAC engineers have carried air properties calculator “wheels” printed on paper disks, capable of calculating single state air properties based on two inputs duct and pipe sizing. While these remain very useful (and don’t require batteries!) the mobile apps that do this same kind of task are more flexible and arguably faster to use. Some of the calculators Cx Associates staff have been finding useful are below:
HVAC Toolkit Carmel Software ($23.99)
A set of utilities that includes a quick load estimation tool, a pipe and duct sizing tool, and an air and steam properties calculator, among others.
HVAC Psychrometric Plus Carmel Software ($6.99)
From the same vendor as HVAC Toolkit, this is the psychrometric (air properties) portion of the tool only.
Munters Psychrometric App Munters Europe AB (Free)
Another air properties calculator and reference tool. This tool is very handy - it calculates single point, mixed air and even calculates tonnage. This is one of our staff's favorite apps.
HVAC ASHRAE 62.1 ASHRAE Inc. ($19.99)
This ASHRAE tool (apparently ASHRAE’s first foray into the app market) facilitates calculations of ventilation rates for acceptable indoor air quality for commercial buildings. While this appears to be the only app from ASHRAE, we look forward to more offerings from an independent, non-vendor source such as ASHRAE.
Bell & Gossett – SystemSyzer Bell and Gossett (Free)
The is similar to the classic old standard red wheel once seen in every HVAC engineering office in the country, now in app format. One nice neat feature is the “unknown pressure drop” mode which allows you to quickly find actual flow in the field if you have design flow/ and differential pressure and actual pressure from field instrumentation.
TacoHVAC Pumps Taco, Inc (Free)
Calculator with pump curves including NPSH, efficiency, and BHP for a nominal selection of pumps.
DALC SMACNA (Free)
A DUCT leakage estimation tool from SMACNA.
Dupont PT Calc Dupont (Free)
A refrigerant properties calculator from one of the major US refrigerant manufacturers.
One of many unit conversion apps available.
Some of the coolest things that can be done using the mobile platforms and apps currently available involve the use of the sensors built right into the device—the multi-axis accelerometers (gyro), GPS receiver, magnetic compass sensors, microphones, and camera. None of the apps that utilize the onboard sensors can be used for critical metering applications requiring a high degree of accuracy—and certainly are not NIST certifiable. But like a good Swiss army knife or multi-tool, they can do a pretty good job in a pinch, though of course can never fully replace the professional-grade version of the tool.
Light Meter Whitegoods (free)
This is a basic light intensity meter which uses the camera as the light sensor to measure Lux.
Dual Level Geometry ($0.99)
This is a very basic level sensor which uses the built in accelerometers.
SPL Meter Studio Six Digital ($0.99)
This is a very basic sound level sensor with filters for different frequency weightings.
Other Apps of Interest
Solmetric iPV Solmetric ($39.99)
iPV is an app that uses all the capabilities of a mobile device to provide the ability to evaluate solar access (availability of the sun throughout the year) for a photovoltaic or solar hot water installation.
TLV ToolBox – TLV manufacturer or rep)
This is a combination reference and calculation tool with many end uses including unit conversion used for unit conversion and steam/condensate pipe sizing. Also has steam tables.