Showing posts with label HVAC. Show all posts
Showing posts with label HVAC. Show all posts

Saturday, November 11, 2017

Clamp-on, Transit-time Difference Ultrasonic Flowmeters Ideal for HVAC Retrofit and New Construction

Transit-time Difference Ultrasonic Flowmeters
Transit-time Difference Ultrasonic Flowmeters (Flexim)
There are many reasons for large commercial buildings, medical centers, museums, airports, sports complexes, federal institutions and military complexes to invest in building energy optimization efforts. Better and more efficient operation of HVAC equipment can reduce the buildings energy and operational costs significantly.

Controlling flow, temperature and pumps can provide energy cost savings of over 20%. Many campus energy managers believe that the biggest user of energy in any complex is the HVAC system, and the key to saving energy in HVAC systems is an accurate and reliable flow metering capability.

Better efficiency of the heating and cooling infrastructure of a building also leads to more environmentally friendly buildings, something that has become a social prerogative of building owners and operators.  Older buildings were not built with BTU meters as metering requirements were added to buildings through increased regulations.

Submetering the buildings heating and cooling systems have become increasingly more important, as building owners are both mandated to meter these utilities and have a financial interest in the accuracy of these BTU measurements. The problem historically is that nearly all flow meters are designed for gradual failure due to direct contact with the fluids they are monitoring and the particulate accumulation on the sensors.

Clamp-on, transit-time difference ultrasonic flowmeters are the ideal retro-fit flowmeter, and also should receive strong consideration for new building construction. Transit-time difference ultrasonic clamp on flowmeters exploit the fact that the transmission speed of an ultrasonic signal depends on the flow velocity of the carrier medium - kind of like a swimmer swimming against the current. The signal moves slower against the flow than with it.

How Transit-time Difference Ultrasonic Flowmeters Work

The flowmeter sends ultrasonic pulses through the process medium - one in the same direction as the
flow and one in the opposite direction. The flowmeter's transducers alternate as emitters and receivers. The transit time of the signal going with the flow is shorter than the one going against. The flowmeter measures transit-time difference and determines the average flow velocity of the process medium. Since ultrasonic signals propagate in solids, the flowmeter can be conveniently mounted directly on the pipe and measure flow non-invasively.

Contact Flow-Tech with your questions about any flow measurement application. Reach them at 410-666-3200, or visit

Tuesday, April 25, 2017

Campus & District BTU Energy Metering

Campus & District BTU Energy Metering
Saving energy through non-invasive
ultrasonic thermal energy management.
Measuring energy consumption for university campuses, medical centers and building systems is increasingly critical for conservation as well as for saving money. Energy and BTU metering of cooling and heating systems through the use of highly accurate, clamp-on flow metering instruments is taking hold in a wide variety of markets. Sectors include: large and small commercial complexes, industrial, government and university campuses, healthcare, and real estate. BTU measurement is an emerging market and is fast becoming critical for entities to remain cost-efficient and compliant. The document below (courtesy of Flexim) outlines the primary areas where this technology is used and how it is implemented. Anyone who manages or maintains a large commercial, medical, or governmental facility should contact a local expert to discuss the savings and efficiencies delivered with well-designed metering and communication system.

Sunday, March 27, 2016

Campus Metering: Improve the Energy Efficiency of Your Building with Clamp-on Flowmeters

Clamp-on, Ultrasonic Flowmeter
Clamp-on, Ultrasonic Flowmeter
(courtesy of FLEXIM)
Today there are many reasons to focus on energy optimization efforts. Due to rising cost of fossil fuels and environmental concerns, decreasing overall energy consumption, decreasing operational costs, improving HVAC performance, improving building quality and certification rating is becoming increasingly important. Facility Managers are stepping up their efforts to find efficiency and savings related to heating, ventilation and air conditioning systems, including chillers, boilers, and air-handling components. Energy-efficiency is a top priority for institutional and commercial organizations and will continue to grow in importance for the foreseeable future.

Finding new ways to reduce energy consumption in buildings without compromising comfort and indoor air quality is an ongoing challenge. One of the most significant options a facility has is to add BTU energy metering that is able to accurately meter the new performance of upgraded chillers, pumps, and chilled water distribution system.

Superior precision can be achieved by using clamp-on flowmeters with specially matched and paired ultrasonic transducers and temperature probes that control the heating and cooling flows within the building. These devices offer a superior solution with a high degree of reliability and repeatability for both temporary and permanent applications.

The biggest challenge in retro-fitting flowmeters in existing piping structures are the very tight piping typical of chiller plants, existing valves, vents, and pipe bends. Clamp-on ultrasonic flowmeters provide an easy work-around. Since the clamp-on ultrasonic transducers are simply mounted on the outside of the pipeline, plant operation is not affected in any way during retrofitting. The reworking of existing piping systems for flowmeter installation is not required, making the clamp-on flow meters an ideal solution for retrofitting existing facilities.

Designed with temperature compensation to eliminate inaccuracies or drift through deviations, and powerful correction algorithms to compensate for non-ideal pipe conditions, these energy flow meters offer an accuracy of 1% or better on the flow rate. Plus, low flow velocities can be detected reliably and accurately.

The advantages for choosing clamp-on ultrasonic flowmeters for HVAC retrofit are:

  • Reliable, non-invasive recording of thermal energy (BTU) flows
  • Practically wear-free measurement without measurement drift, unaffected by potential coating formations
  • Works independently of the conductivity of the medium
  • Simple set-up of measuring points without any interruption of operation
  • Minimum installation effort
  • Compact measurement system, can also be easily installed on measuring points which are difficult to access

Research demonstrates the addition and/or upgrade of metering existing HVAC systems can offer effective solutions for energy conservation and thermal comfort, with possible energy savings in the range of 30-40%.

For more information on BTU/Campus/Building Metering, contact:

Flow-Tech, Inc.
10940 Beaver Dam Rd
Hunt Valley, MD 21030
Ph: 410-666-3200

Central VA Office
10993 Richardson Rd#13
Ashland, VA 23005
Ph: 804-752-3450