|This project presented many design challenges as the project evolved. A slab-on-grade luxury home on a small lot was just the beginning. The major challenge was the relatively complex mechanical system needed to be installed in an ever-shrinking mechanical space. We redesigned the mechanical room 4 times and found creative ways to fit the major mechanicals into approximately 25% of the original space allocation. The mechanical room is in the garage and is highly visible to the customer each time they come home. We took great care to achieve the form and function required for this project with this customer. Unique features include:
Some of the more mundane details below: The 5 ton system with two (2) 400’ boreholes to adequately support the thermal exchange with the heat pump. A WaterFurnace NSW 5 Ton Water-to-Water unit was selected to serve the radiant floor zones and air handlers for heating and make chilled water sent to air handlers for air conditioning. At the customer’s requests a wall mounted IBC Modulating 20K to 115K BTUH Boiler will be installed to serve as a supplemental and back-up heating source to the house’s hydronic heating system and serve an 80 gallon IBC indirect water tank for domestic hot water. The boiler will be located in the garage mechanical room connected to an insulated 40 gallon Geo-Stor tank acting as a buffer tank for the hydronic heating system. The buffer tank also takes heat inputs from both the geothermal heat pump and/or boiler depending on preset conditions. To maximize the system efficiency an HBX Set Point Controller will adjust water temperatures sent to the heating zones from the buffer tank, in response to changes in outside air temperature. A separate HBX Zone controller will also be used to regulate zone valves for each of the hydronic zones for the radiant floors and air handlers in the system. This system won the Best Mechanical System Award at the CRBRA Best in Building Awards in November of 2018!!
- Custom aluminum equipment rack with hinged access door with controls mounted in door.
- BlueDuct underslab ductwork serving first floor.
- Two Air handlers – one conventional ductwork and one high velocity to meet design constraints.
- Radiant floor zones and air zones match so one thermostat controls all zone functions.
- Interfaces with Savant home automation system installed by others.
- Kilfrost GEO used instead of propylene glycol to lower freeze protection and pumping energy.
- Two HRVs serve as whole house ventilation and double as bathroom ventilation on timers.
- Exposed spiral duct in loft area.