Mechanical Technologies

Why do water coils require a minimum GPM? 🤔 Turbulence is needed to ensure the fluid makes sufficient contact with the inner walls of the water coil. More contact means more heat transfer. If a fluid moves too slow, it becomes uniform and laminar (think straight lines). Due to frictional forces at the walls, the water flows primarily through the center of the tube. This results in less contact with the side walls. The minimum velocity in a tube is 0.5 ft/s for chilled or hot water coils (according to Table 1 of AHRI 410). For a 1/2" nominal diameter tube, this translates to approximately 0.31 GPM. Keep in mind this is per circuit, so multi-row coils, which will likely have multiple circuits, will need a greater GPM. For more information, refer to the AHRI standard or a college fluid dynamics textbook. #mechanicalengineering #hvac #airdistribution

Today’s (5/24/24) #FunFactFriday is on cold weather operation of a cooling tower, specifically with VFDs and running the tower in a temporary de-ice mode. Ice can form on #coolingtowers that operate in the winter in northern climates. To prevent ice buildup, and to help melt any ice that did form, the cooling tower can be occasionally operated in the reverse direction. In reverse, the warm air is pushed out the sides instead of the top of the tower, thus melting ice buildup on the sides. I’ve shared two Youtube training videos on how to implement cooling tower de-ice mode with VFDs. The first video is for a situation with just a #VFD, and the second video has the solution for when there is an ABB E-Clipse bypass. There are a variety of ways to implement the controls for de-ice mode, ranging from contact closures all the way to BACnet integration/control. Leverage the video timestamps to jump to the method you’d be interested in doing it. De-ice with drive only: https://lnkd.in/ghfmVeyy De-ice with bypass: https://lnkd.in/ghgcbU2r It isn’t my image, but I’ve always liked the simplicity of this image below. Blue arrows are the normal operation, red arrows are the de-ice mode.

Today’s (5/17/24) #FunFactFriday is Part 2 of a training series on tools to troubleshoot a drive. Last week I covered the Event Logger, and now I’m covering the Fault Logger. We will use the #ABB ACH580 drive as an example in the video, but many of the concepts apply to other models/brands of drives.  Like the Event Logger, the Fault Logger has that mini-BAS (trending & alarm log) concept right in the drive. Faults are something that stop the drive from operating, so it can protect itself. Temperature, voltage or current levels, that exceed the drive’s capability, are all items that can generate a fault. For example, a short in the motor wiring will cause the drive to fault to protect itself. Drives will typically have a fault logger, or a fault history, that states what the faults were and what the operating conditions were of the drive at the time of fault. Those operating conditions can be key to #troubleshooting unexpected or nuisance faults.  Link to 9 minute Youtube training video on the Fault Logger: https://lnkd.in/gfYfypjF Link to last week’s Event Logger LinkedIn post: https://lnkd.in/g9QJ2aN3

✏️ TAKE NOTE! Most engineers only consider max cooling CFM when specifying and laying out diffusers. Min cooling CFM should also be considered because the system will be running at less than max cooling CFM the majority of the time. And while we might “know” that not all diffusers perform alike, it’s very different when you see them side by side. In this video, we show how the PLQ provides better throw (even during turndown) than the perforated 6600 diffuser. *Demo performed with 55° supply air temperature. #mechanicalengineering #hvac #airdistribution

Thank you to our partner Coward Environmental Systems Inc. for this great article explaining why ArctiDry is positioned to revolutionize the industry. Our focus on dehumidification, lowering energy consumption, reducing refrigerant use, and improving indoor air quality for commercial buildings, makes ArctiDry an ideal solution for applications, such as hospitals, grocery and schools, that require Dedicated Outdoor Air Systems (DOAS). Read the interview with our VP of Product to learn more about our novel liquid desiccant system that is changing the nature of air conditioning. #ArctiDry2024 #climatetech #HVAC #commercialairconditioning #airconditioner #HVAC

Today’s (5/10/24) #FunFactFriday kicks off a training series on tools to troubleshoot a drive. This is Part 1, next week Friday will be Part 2. A #HVACR #VFD will typically have logging capability for faults and some drives also have logging of events.  This Part 1 training is about the Event Logger. We will use the ABB ACH580 drive as an example in the video, but other drives may have similar capabilities.   The Event Logger is like a mini-BAS (combination of trending & alarm log) right in the drive. Event examples: Power applied, Hand-Off-Auto state changes, start/stop commands, modulation started/stopped, a safety opened, warnings, and more. Having this data right on the drive’s display makes it much easier to troubleshoot. The event timestamps, allow you to visualize the exact sequence that led up to the “issue” that you are troubleshooting. For example, is someone complaining about an area being too hot and the #HVAC system not keeping up for the past week? You then go to the drive and see someone placed it from Auto to Hand mode, and the drive is only running at half speed.  If the Event Logger shows it was placed into Hand mode a week ago – then that explains why the system wasn’t keeping up for the past week. The new mystery is who placed the drive in Hand mode – but since we don’t have fingerprint identification or built-in cameras in the drive, that one may be harder to answer😊 Youtube link to under 10 minute training video on Event Logger: https://lnkd.in/gA6vwsWR Nice video Jeff Brunner

We've got some big ass news! Beginning this week, Mechanical Technologies will be your representative for Big Ass Fans! Big Ass Fans brings industry-leading airflow and energy savings to customers worldwide. They started with a big idea in engineering: that the combination of size and quality design could fundamentally change what ceiling fans could accomplish. Their high-volume, low-speed (HVLS) airflow concept was the key to making spaces more comfortable and efficient. Learn More: https://lnkd.in/evGyhtwH or contact your local Mechanical Technologies sales representative. Clara Merino Chris Panza #Engineering #HVAC #CeilingFans #BigAssFans #AirFlowTech

We've got some big ass news! Beginning this week, Mechanical Technologies will be your representative for Big Ass Fans! Big Ass Fans brings industry-leading airflow and energy savings to customers worldwide. They started with a big idea in engineering: that the combination of size and quality design could fundamentally change what ceiling fans could accomplish. Their high-volume, low-speed (HVLS) airflow concept was the key to making spaces more comfortable and efficient. Learn More: https://lnkd.in/evGyhtwH or contact your local Mechanical Technologies sales representative. Clara Merino Chris Panza #Engineering #HVAC #CeilingFans #BigAssFans #AirFlowTech

Space is filling up quick for our next in-person PDH session, hosted at our New York City headquarters! Make sure to get your ticket for this 2.0 PDH credit presentation covering AHRAE Standard 170 and high-pressure atomizing humidification. Thursday, April 25th 5:15PM - 6:15PM EDT Mechanical Technologies HQ 498 7th Avenue, FL 14 New York, NY 10018 Space is limited! Snacks and beverages will be provided. We hope to see you there! Register Now: https://lnkd.in/eGHVDCdD #hvac #engineering #freecourses #professionaldevelopment #inpersonclasses Shawn Mageean Mikaela Kane Lawrence Bovich

We're inviting you to attend a new free PDH course, offered in person at our NYC Headquarters! This month will feature a 2.0 PDH credit presentation covering AHRAE Standard 170 and high-pressure atomizing humidification. Thursday, April 25th 5:15PM - 6:15PM EDT Mechanical Technologies HQ 498 7th Avenue, FL 14 New York, NY 10018 Space is limited! Snacks and beverages will be provided. This is a series of monthly educational seminars that will be hosted by Mechanical Technologies and our manufacturers. We hope to see you there. Register Now: https://lnkd.in/eGHVDCdD #hvac #engineering #freecourses #professionaldevelopment #inpersonclasses Shawn Mageean Mikaela Kane