Diagnosing a healthy building
A diagnostic site visit with the right tools can reveal the hidden dynamics and interactions between the building shell, the heating system, and other building features. A thermal imager, for example, can quickly reveal missing or inadequate insulation, which is a major contributor to heat loss. Collected data from a full kit of handheld diagnostic tools can be used to quickly locate and accurately diagnose existing or potential problems. Otherwise these problems may jeopardise not only building performance in terms of energy efficiency and the comfort of its occupants, but also compliance with building, health and safety regulations.
Building diagnostics involves identifying and troubleshooting anomalies throughout an entire building. A number of separate yet inter-related conditions should be checked on a regular basis to identify potential problems in the way the building or its systems are operating. A wide range of performance issues directly related to the building tightness, the quality of insulation, indoor air quality, and the effectiveness of ventilation systems can be quickly and accurately revealed with the right diagnostics tools. The range of tools needed includes infrared thermometers, thermal imagers, indoor air quality meters and airflow meters. All of these troubleshooting tools should be available as rugged, handheld tools in the tool kit of the building maintenance technician.
Building diagnostics checklist
Whether at an industrial plant, in a commercial office or residential buildings, frequent inspections of the building envelope and the environmental conditions inside are important for maintaining healthy and efficient buildings. The following is a list of areas to be monitored.
1. Moisture Intrusion
Moisture intrudes through joints and cracks in roofs, ceilings and walls, and is trapped, resulting in structural rot and mould. Regular inspections with a thermal imager, inside and outside of structures, will quickly locate areas of accumulated moisture. If mould is suspected, temperature and humidity readings can be taken using a temperature humidity meter to determine whether suspected areas have fallen below dew point levels.
2. Heat loss
The quality of insulation inside the building, as well as numerous other areas where heat loss can occur (such as breaks in building seals), should be inspected. Temperature scans inside and outside of structures – along ceilings, floors, walls, windows, doors, vents and pipes – immediately indicate the problem areas.
Using an infrared thermometer to scan walls, floors and ceilings will quickly determine whether room temperatures are equally balanced. Then, if differences are found, a thermal imager will quickly locate sources of heat loss, such as insufficient insulation or broken seals.
3. Indoor air quality
Conditions that promote a healthy, productive environment and greatly reduce the number of occupant complaints should be actively monitored. Measurements that should be taken include air temperature, relative humidity, airborne particle concentrations, and levels of CO2 or carbon monoxide (CO) gases.
CO2, which is a bi-product of respiration, can indicate the rate of fresh air exchange into an indoor space, use of an indoor air quality meter will check that temperature, humidity and ventilation are within comfortable levels. A particle counter can also be used to verify air filter effectiveness to ensure that indoor air particulate levels are less than outdoor levels. An air flow meter will measure the pressure and movement of air within the building to locate leaks in ducts as well as malfunctioning ventilation and exhaust systems.
4. Furnaces and boilers
A variety of measurements can be made to inspect the performance of the heating system and to identify repairs that need to be made. A true-rms clamp meter (with temperature measurement function) can be used to compare micro Amps DC with manufacturer specifications and to verify that flue gas temperatures are within acceptable limits. An indoor air quality meter can check for excess levels of CO2 and harmful carbon monoxide in the area around boilers and furnaces. Harmful levels of carbon monoxide indicate problems with the ventilation/exhaust system, or the presence of leaks. A scan of the furnace or boiler exterior with a thermal imager will check the inside insulation – hot spots indicate a need for repair.
5. HVAC system performance
For greater efficiency and extended equipment life, the proper operation of building HVAC systems should be verified on a regular basis. A thermal imager or infrared thermometer will locate hot spots on operational components, which indicate pending mechanical or electrical system failure. Electrical connections can be checked with a true-rms clamp meter. Over/under voltages are likely to indicate reliability problems and potential failures.
Increase the efficiency, comfort and structural integrity of industrial, commercial and residential buildings by regularly monitoring heat loss, moisture invasion, indoor air quality, as well as the performance of heating and ventilation systems.
Now available in rugged, low-cost versions specifically designed for ease-of-use by maintenance technicians, they can detect hidden anomalies and provide detailed, ultra-high quality images with full radiometric measurement. They will also provide visual and thermal images and the professional report writing software uses stored readings to ensure accurate reports.
Versions are available that combine contact and non-contact readings for complete surface temperature checks. The non-contact infrared (IR) thermometer is ideal for quick scans and the Velcro fitting pipe probe ensures easy contact measurements.
Air Monitoring Tools
Handheld versions are available to provide complete monitoring in order to optimise building comfort. They measure temperature, humidity, CO2 and CO levels, air flow rate and velocity and the easy data logging and reporting functions makes them ideal.
For temperature and humidity checks, they measure dew point and wet bulb temperatures and display and log MIN/MAV/Avge values.
Handheld tools are available to measure airborne particle concentrations for particle sizes down to 0.3µm. They have user-selectable measurement parameters for greater flexibility and are capable of storing up to 5000 data records, which can be uploaded easily to a PC.
Air Flow Meters
All-in-one tools are available for complete ventilation/exhaust system checks that measure differential/static air pressure, air flow and velocity. The colour-coded hoses are easy to set-up and use and they include user-definable parameters.
True-rms Clamp Meters
Versatile service tools are available for HVAC system diagnosis which measure capacitance, DC current (µA) and temperature and have a CAT III 600V rating for optimal safety.