Case Study: Form & Function Coexist
By Mike Murphy with Lauren Fusco, www.contractingbusiness.com
Vicki Cottam swears that her husband goes out of his way to find the largest, most complex jobs — because they’re the most challenging. From the very beginning, Gary Cottam of Cottam Heating and Air Conditioning Inc., knew this project was going to be a challenge, but one he gladly accepted.
The home, a beautiful, Georgian-style center hall colonial, was built in the 1930s. A major concern expressed by its owners was to preserve the beauty and integrity of the past. The home sits on slightly more than one acre of land in a quiet residential neighborhood. The customers, who wish to remain anonymous, had many concerns about preserving the aesthetics of the home. Ornate moldings and floor-to-ceiling, antique single-pane glass, French doors decorate many of the 13 rooms in the 7,595 sq.ft. home. They were worried that moldings and doors might be damaged during the restoration/renovation. Additionally, they didn’t want to open up the living room walls to run ductwork, fearing that intricate, antique detail on the walls would be ruined. Nor did they want to lose any ceiling height in the basement; new ductwork was out of the question.
Cottam Heating and A/C took careful precautions to work around the moldings and elegant glass doors, and to preserve the eight and one-half ft. ceiling heights in the basement. Gary Cottam says, “It’s always my intention to provide a customer with an efficient system, and to install that system in such a way as to leave them satisfied and content.
“Though many of my concerns dealt with the homeowners' desire to preserve the integrity of the home, I also struggled with how to design the best HVAC system. The owners wanted the temperature to be accurate, constant, and to include proper zone control,” Cottam continues.
The remodeling restrictions certainly created a challenging work environment. But wait, there’s more.
The owners didn’t want noisy outdoor units placed near the large glass doors, nor did they want to inconvenience any of the neighbors. They even wanted to hear the operation of a similar system to confirm the noise level would be acceptable. Then, the local township couldn’t determine where an outdoor chiller could be located in accordance with local code. Finally, after many meetings with the town and architects, a solution was reached — the chiller was set 10 ft. from the lot line.
The homeowners' main concern, however, was for their daughter's unique bedroom. Though based on the second floor, it extended upward, via a Chinese staircase, to a sleeping loft in the attic area. They were concerned their daughter would have to sleep in extremely uncomfortable, hot conditions.
All of these concerns were reviewed in the early stages, making it easy to understand what the customer wanted from this installation. However, one unexpected component of the design was the constantly changing remodelers plans. As each room was begun a new issue would be uncovered by the general contractor and architect. Cottam had to adjust the HVAC plan on short notice, several times.
“I knew I would have to put a lot of time, energy, and thought into designing the perfect HVAC system; but the end result proved that nothing compared to how much the homeowners and I got out of it,” says Cottam.
System Design and Installation
Walking through the house with the homeowners and general contractors, Cottam began to formulate ideas of what this HVAC system should look like. He began the design process with load calculations, zoning options, and drafting plans.
To correct the situations in the daughter's bedroom/attic loft and the master bedroom, the company installed a 2-ton Trane variable speed air handler and a 2-ton, 12 SEER, Trane condensing unit for each of the respective areas.
The three other guest bedrooms were conditioned by a 3 12-ton Trane variable speed air handler and a 3-ton, 12 SEER, Trane condensing unit. Hot water coils were included in all three of these bedroom systems to function as the primary source of heat. Additionally, radiant floor warming and remote Fantech exhaust fans were installed in all bathrooms. Cooling for the entire upstairs will be available at any time of the year, even if the chiller is shut down for the season.
A huge challenge was found in the first floor and basement areas. The customer wanted a zoned system with minimal outdoor units. Cottam installed one Trane 10-ton chiller with six Magic Aire fan coils to handle the areas. All fan coils are four pipe systems, that provide both heating and cooling. In order to obviate any noise issues, the 10-ton chiller was installed 180 ft. away from the basement mechanical room, with consideration taken for nearby neighbors.
Chilled water piping presented two dilemmas: 1) to run piping from the chiller 180 ft. away to the chilled water pump located in the basement mechanical room, and 2) to run piping from the chilled water pump to the fan coils located throughout the house. An Ecoflex flexible pre-insulated plastic pipeline system was installed three ft. below grade level and run to the chiller. Cottam used Stadler Fostapex flex tubing with Bell & Gossett circuit setters for water flow balance on all of the fan coils.
Cottam installed one Trane ducted system to feed the first floor conservatory room, and four Trane inverted, vertical recessed forced-flow cabinet heaters to serve the living room, foyer, and mud room. This accommodated the homeowner's request to eliminate basement ductwork and unsightly registers.
Perhaps the most magnificent room in the home is the personal office on the first floor. Four beautiful French doors encase the room. The large amount of glass in the room, and subsequent cooling and heating loads, encouraged Cottam to design an independent zone, served by a Magic Aire fan coil and hot water coil for heating, radiant floor warming beneath the hardwood floors, and unobtrusive wood floor registers.
Yet another antique, ceiling-to-floor French door adorns the family/billiard room located on the first floor. A Magic Aire fan coil unit is installed in the crawl space below the area. All return grilles were eliminated. The project's general contractor, provided custom-designed slot details in the room’s custom millwork. Radiant floor warming adds an extra dimension of comfort in this beautiful room.
The basement area consists of laundry, exercise, and hallway areas. All are conditioned with one Magic Aire fan coil unit.
The media room, with a unique, state-of-the-art, color-changing, lighted ceiling, is conditioned by a Magic Aire fan coil unit. All ductwork is acoustically lined and the ceiling is lined with vibration isolators in such a way that no sound could be transmitted from the media room to the rest of the structure when the theater is in use.
The wine cellar heating, air conditioning, humidification, and dehumidification systems consists of a Magic Aire fan coil unit, condensing unit, Johnson Controls temperature and humidity sensors, and an April Aire humidifier, and electric duct heater.
The Buderus hot water boiler, located in the basement, provides heat to 13 zones and serves the radiant system, for the entire house. The radiant system uses Stadler injection stations with three remote manifolds to modify the floor warming temperature based on outdoor temperature. Radiant heat is used in the basement, beneath the tiles in all bathrooms, and below hard wood flooring in areas, such as the bedroom above the garage and the majority of the first floor living space. Additionally, the two garages are heated with Modine Hot-Dawg heaters.
The Stadler-Viega radiant heat is controlled by AR-5 and AR-10 zone panels. An Argo zone panel controls the operation of the Bell & Gossett circulator pumps and the Buderus boiler. Honeywell remote sensors turn off the chiller operation at 65F.
Cottam created a unique system to control the operation of the multiple living room Trane recessed fan coil units. Using a Trane Z-10 control board and remote thermostat, he was able to link the operation of the multiple living room fan coils to only one thermostat.
Testing and Balancing
Cottam Heating and Air Conditioning, Inc. performed an in-house testing and balancing for all airflow with an Alnor Flo-Hood. Cottam contracted the services of a certified test and balancer to confirm the flow of all the chilled water.
Gary Cottam happily reported that not one problem has arisen since the completion of the job, and the homeowner has been extremely pleased. “For an entire year, my company and I had the pleasure of working with the homeowners on their HVAC installation. I was extremely pleased to find two people who were so conscientious of their neighbors and quality of life issues.
“Keeping in mind the needs and wants of my customers, I designed and installed a multiple-zone heating and air conditioning system for their home, including ductwork," says Cottam.
That sincere desire to satisfy customers has earned Cottam Heating & Air Conditioning, Inc. a 2004 Quality Home Comfort Award winner. Congratulations on proving that comfort and beauty can coexist with form and function.
- Trane CGA 10 ton chiller
- Trane FCHB fan coil units with hot water coils (4)
- Trane Z-10 control board
- Magic Aire DHW fan coils
- Buderus G334 boiler
- Stadler Fostapex tubing
- Bell & Gossett circulator pumps
- Trane 2TTR 12 SEER condensing units (3)
- Trane TWE variable speed air handlers (3) with hot water coils
- Modine HD30A Hot Dawg heaters (garage)
- White Rogers IF80 thermostats
Radiant system (basement, first floor bathrooms):
- Wirsbo DT-10 thermostats
- Stadler Viega AR-5 and AR-10 zone panels
- Stadler radiant PEX tubing