Building Energy Resilience

Ideas to fuel a sustainable built environment

4 min read

How to Avoid Air Handling Unit Steam Coil Issues

By Tate Colbert on Oct 7, 2020 11:00:00 AM

Basics of steam coil and face and bypass operation

Many air handling units in colder climates are equipped with steam heating coils. These coils use control valves to modulate the flow of steam to the coil. Due to the low mass of water in a steam coil, it has a higher propensity to freezing when conditions are right. One of the neat ways we’ve design around this is to use a Face and Bypass (F&B) damper arrangement to allow the coil to have maximum steam flow to prevent freezing. The F&B dampers direct a portion of the airflow through the steam coil and another portion bypasses the coil in order to achieve the necessary discharge air temperature and prevent a freezing airstream from damaging the steam coil. Pretty neat, huh?

Topics: HVAC
7 min read

Reopening Schools: Understanding and Prioritizing HVAC Preparedness

By Eveline Killian on Jul 6, 2020 10:15:00 AM

The prospect of reopening schools under the new CDC guidelines in response to COVID-19 can be overwhelming for facilities and administrative personnel. In addition to increased surface cleaning, hand washing, maintaining six feet between classroom desks, and wearing face masks, the schools are faced with making decisions on how to best operate their HVAC equipment. As much as the world is trying to help them with these decisions, the HVAC guidelines from the CDC and ASHRAE are all encompassing; it is difficult to identify which measures are applicable and even more difficult to prioritize the measures under a school’s constrained budget. This may overburden an already burdened school facilitator. 

Topics: HVAC Higher Education Existing Building COVID-19 PK-12 Education problem solving
5 min read

Making our Commissioning Process Remote

By Katie Mason on Apr 22, 2020 10:00:00 AM

With the current COVID-19 global crisis, organizations all over the country are actively seeking ways to continue to provide the same level of services to their customers while keeping their employees safe. Cx Associates is known for its rigorous standards in the commissioning process, but a large portion of our work is contingent on our ability to be on construction sites, working with contractors to verify the installation and functionality of equipment. With Vermont’s order that all non-essential employees work from home, and with Cx Associates’ commitment to both keep our employees safe and prevent us from potentially spreading the virus on construction sites, we needed to quickly find a way to provide our on-site services remotely for the essential construction work that continues to move forward in a way that still matches our high standards. This blog discusses our approach to remote site work and how we're continuing to serve our clients while safely social distancing from our home offices.

Topics: Building Performance & Technology commissioning HVAC Heat Pumps technology Utility building automation system COVID-19 coronavirus remote problem solving
4 min read

COVID-19 & the Race for Isolation: Part 1 – Cooling & Dehumidification

By Matt Napolitan on Apr 2, 2020 11:00:00 AM

Hospitals are racing to create as many isolation rooms as possible to help effectively care for patients with COVID-19 while keeping healthcare providers and others in the hospital as safe from infection as possible.

Topics: Healthcare HVAC Existing Building COVID-19 coronavirus isolation rooms negative pressure problem solving
3 min read

Challenges with Rooftop Units and Factory Controls

By Jamie Hand on Jan 15, 2020 10:00:00 AM

After an early morning departure and a snowy drive, my colleague and I arrived onsite to test, among other equipment, a packaged rooftop air handling unit with factory controls. At first, the unit appeared to check all our boxes, but as we dug into the details, it became clear that this would be a very expensive heating system to operate. This blog entry is about factory controls and the importance of getting into the weeds to identify issues like the one we found with this rooftop air handling unit.

Topics: Building Performance & Technology commissioning HVAC Factory Controls Energy Management New Construction Existing Building Energy Planning
3 min read

USP 800 Pharmacy HVAC Testing – The Devil is in the Details: Part 1

By Matt Napolitan on Oct 23, 2019 10:00:00 AM

A large healthcare client of ours recently opened a brand new USP 800 compliant compounding pharmacy, which we commissioned. We collaborated with the engineering team and the hospital during the design phase to help ensure prior issues weren’t repeated, and the hospital’s concerns were thoroughly articulated and addressed. At the conclusion of the design phase, the team was confident that the design direction was solid and would give the hospital what they were looking for.

Topics: Healthcare commissioning HVAC USP 800 New Construction problem solving
4 min read

Understanding the Basics of a Ground-Coupled (Closed Loop) Heat Pump Design: Part 1

By Tate Colbert on Oct 9, 2019 10:00:00 AM

The ground source heat pump is a wonderful technology that will be vital in achieving energy efficiency goals this century. This technology isn’t new, but it is beginning to become more accepted as a viable solution for large scale, high efficiency HVAC performance. There are two main types of ground source heat pump systems: those that are “Ground Water” (also called Open Loop) and those that are “Ground-Coupled” (also called Closed Loop), see Figure 1 below. In either case, the water from the ground is pumped to a heat pump, where heat is either extracted out of or rejected into the ground and moved into or out of the conditioned space.

Topics: commissioning HVAC Heat Pumps Energy Management New Construction
3 min read

Occupant Based Controls for Energy Savings

By Daniel Tuhus-Dubrow on Jul 3, 2019 10:00:00 AM

I recently attended the Performance Evaluation Methodology for Building Occupancy Sensing Systems for HVAC Controls workshop, which followed the annual ASHRAE conference that just wrapped up in Kansas City, MO. The workshop focused on one of ARPA-E’s[1] research programs called SENSOR (Saving Energy Nationwide in Structures with Occupancy Recognition)[2], and brought together a diverse group of individuals, including researchers from national labs and universities, industry representatives, design engineers, and other interested parties.

Topics: Standards and Metrics Building Performance & Technology HVAC New Construction Existing Building Controls upgrade Efficiency Program Program Evaluation energy efficiency program M&V

Featured