15000, Inc.

Corte Madera Town Center – A Tale of Two Boilers

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15000 Inc. > Specialists in boiler and heating water systems.

When the Corte Madera Town Center started having problems with their 30 year old boiler they called in the experts to assess the problem.

The Town Center is Marin’s premier shopping destination and in many ways reflects the lifestyles of the rich and famous. It is a beautifully designed mall with cobblestone walkways, high end stores and unique eateries. Like their customers, the tenants of the center have high expectations. These expectations include having an exceptional environmental control system for their discerning clients. Simply put, being too hot or too cold is not an option.

The Center is served by a central water source heat pump loop which provides condenser water to the individual heat pumps within the tenant spaces. The heat pump loop temperature is maintained by an open circuit cooling tower and a heating boiler system. Water is circulated throughout the Center via two large inline pumps.

The old Bryan Flex Tube Boiler
The 30 Year Old Bryan Boiler at the Corte Madera Town Center

 

The 30 year old Bryan boiler began having a number of problems. The electronic control system was worn out and had became the source of frequent problems. Small leaks in the piping, and around the boiler, suggested some of the internal components were failing as well. Maintaining the condenser water loop temperature during the winter was becoming a challenge, especially on colder days.

Tom Guilfoyle, the director of facilities for the Center, knew what he wanted:

“I need a modern high efficiency boiler system with digital controls and a plain English interface controller for operation and troubleshooting. When all is said and done I need to be able to demonstrate to upper management that we have a reliable system that is going to save us in energy costs.”

Although this sounded like clear direction, a number of decisions needed to be made.

There is a wide selection of boilers available in today’s market, any one of which might have met Tom’s expectations. In addition, a key decision point was the limited access to the boiler room. In essence, if it couldn’t fit up the stairs, it wasn’t an option.

15000 Inc. developed a Boiler Comparison Matrix to aid in the decision making process.

15000 Inc. Boiler Comparison Matrix

15000 Inc. Boiler Comparison Matrix

The matrix was reviewed with the facility and the decision was made to use the Raypak XTherm system. The original system employed a single 3,000 MBH boiler with limited capacity control. The flex tube boiler was not really intended to work with the low water temperatures of a heat pump loop.

The new system would employ condensing boilers which are ideally suited for low water temperatures. In fact they are at their most efficient under these conditions. In addition we employed two boilers, sized at 1/3 and 2/3 of the load. This selection allowed the smaller boiler to handle the loop heating during the low loads which occur most of the year in this climate. When the load exceeds the capacity of the small boiler it shuts down and the large boiler is energized. If the loop setpoint is still not met, then the small boiler is re-started to run in conjunction with the large boiler. This sequence of operation allows the most efficient use of the boilers and ensures stable loop temperature control.

The installation was done by Matrix HG Inc., experts in boiler installations. They worked closely with the facility to schedule the work to minimize the impact on the Center. The end result was a model of quality workmanship.

The two Raypak XTherm Boilers now serving the Corte Madera Town Center
The two Raypak XTherm Boilers now serving the Corte Madera Town Center

The facility has been operating for two months and Tom has reported that the new system is running perfectly. He is anxious to see the reduced energy bills the new system will produce.

15000 Inc. is proud to have assisted the Corte Madera Town Center with this project. It is also comforting to know that rich and famous will be environmentally controlled in the manner to which they have become accustomed.

Incidentally, no one at 15000 Inc. can afford to shop here yet – but a few more projects like this and it just might elevate us into that tax bracket. (Ok, that’s not going to happen but we can can still hang out in the garden court and watch the cool people… we’ll be the dorks with the roll of drawings and the calculator.)

About the Author
Gary Welch is a principal of 15000 Inc. with over 40 years experience in the field of HVAC, plumbing and fire protection design. He can be reached at gary@15000inc.com.