To begin to understand the principles of energy savings with occupant comfort, one must understand the concept of pressure independent systems couple with variable frequency drives (VFDs). VFDs are utilized in both air side and wet side applications, but for this application we will be discussing hydronic systems. In short, a VFD enables a hydronic system to operate more efficiently through multiple pump system curves versus the age-old method of single speed pumping with modulating pressures (substantially less efficient).

Joe Stagg - Pipeline Development Company

I met Joe earlier this month at a training seminar for the pump manufacturer that I represent outside of Atlanta. His company, Pipeline Development Company, shares a similar motive with HVACLive in their intent to provide free, un-biased education to the HVAC industry. Through on-site training classes or webinars he offers continuing education and PDH credits.

When he began his presentation he talked about his role as an educator and how he taught classes on systems/products without directly promoting the affiliation for which he had been sponsored by. He has a background as a sales representative and I found his approach intriguing.

His experience and education background led to the simplest and easiest presentation that I've ever attended when it comes to hydronic systems. The best way for you to understand this topic is to hear it first hand for yourself directly from Joe.

Click here, and enjoy...

 
 

Introduction

MJ Mechanical is in the process of redesigning the existing system that provides heat and hot water for a large building for one of our customers. The building contains office space requiring domestic water (showers, sinks) as well as a swimming pool for the occupants. Our redesign of the existing system required an energy analysis of the current setup in order to be able to size the new
equipment, and to calculate the capacity of the replacements. For the purpose of this case study, we will look at the domestic hot water/pool heating analysis of the project.
 
 
In our field we frequently deal with applications where we use wall penetrations to relieve and intake air. It could be the need for bathroom exhaust, makeup air intake, emergency purge exhaust, or even general building pressure intake or relief. For this case-study, it is for emergency generator intake and exhaust at a new-construction project for the Erie County Medical Center. If the building loses power and the emergency generators are required to kick on, the dampers will open to allow combustion airflow into the space. 

For this application the dampers will be closed 99% of the time. The space within is still conditioned (heated and cooled) and energy loss through wall penetrations can be great if not properly considered with a preventative approach. This was a legitimate concern for the design engineers. The wall cavity sections at ECMC are large - roughly 100 square feet a piece. They know that in order to maintain a high-performing energy system they will need to minimize all wasted energy through this area.