Note: This article wass written for a precision diagnostic equipment.
Measuring depressurization caused by exhaust devices, air handlers and door closures is not something new in the field of building science. The Energy Conservatory has had a procedure in its blower door manual for over 20 years. There are many recommended procedures and protocols out there, but they all require documenting changes in pressure. If you want to diagnose solutions to depressurization issues, you’ll want to document incremental pressure changes as each additional exhaust appliance is turned on, as well as document the effects of the air handler and door closures.
Using the TEC WiFi Link with the iTEC-700 iOS or Android app has made this documentation easier. You can leave the DG-700 in the Combustion Appliance Zone (CAZ) and view the changes in pressure caused by turning on exhaust devices on a phone or tablet via a WiFi connection.
To document these changes, use iTEC-700 to change the readings to a 10-second average, and then take a screenshot of the results at each step.
If you already have a computer in the field, an even better way to document pressure changes at each step is to use our free TECLOG3 software. TECLOG3 can display and record real-time CAZ-to-outside and water heater vent pressures. You can easily add and label event markers in the software or create periods of record that will calculate long-term averages of these pressure changes.
Using the TEC WiFi Link for Data Logging Pressures
The TEC WiFi Link as a stand-alone data logger
There are many possible applications where measuring pressures over time would help you diagnose pressure-related issues in a home or business. Here’s a short list of a few of the many possible applications:
- Frequency of use of exhaust devises or air handlers
- How often are multiple exhaust devises on at the same time
- Building pressure changes caused by exhaust devises
- Pressure in CAZ and chimney vent
- Pressures between two zones, such as an office space and a warehouse storing chemicals
- Pressure changes when exhaust devices and ventilation systems are used in those two zones
Our TECLOG3 software has been available for years to support these applications, but it required leaving a computer on-site to gather the data.
The WiFi Link accessory for the DG-700 has memory that will allow you to leave just the DG-700 with a WiFi Link attached to gather the data. The sampling interval can be adjusted to allow you to record samples over extended lengths of time. Some examples are:
- Data points at 1 second interval for 8 daysgauge
- Data points at 5 second interval for 40 days
- Data points at 60 second interval for 485 days
You get the idea. The length of time the gauge batteries will power a stand-alone data logging session depends on the power level of the batteries installed, and the auto-zero interval – the longer the auto zero interval, the longer the batteries will last. A fresh set of alkaline batteries and an auto-zero interval of 60 seconds will provide approximately 8 days of power for data
logging. It’s also possible to power both the gauge and WiFi link with a wall power adapter and a custom Y-connector available from TEC.
Putting the WiFi Link in data-logging mode
You will need to use the iTEC for PC software to launch the WiFi Link to data-logging mode and to retrieve the data. This software is a free download from our website and can be found here.
Analyzing the data
The data retrieved from the WiFi Link can be viewed in our TECLOG3 graphing software or loaded into an Excel spreadsheet.
For more about precision diagnostic equipment see these articles.