Arborfield & District Health Centre

Retrofit Activities with current status
(click each activity for detailed retrofit construction information)

Lighting
The following table provides descriptions of the existing and proposed lighting conditions for different areas of the facility.

Main AHU Zone Isolation
Overview
The Arborfield & District Health Centre has a main Air Handling Unit (AHU) which supplies the majority of the facility excluding the Kitchen and Laundry areas which have their own Roof Top Units (RTUs). The main AHU is a mixed air system and operates on a 24/7 basis. While supply air must be maintained to areas with 24/7 occupancy, such as the wards and nursing station, there are other areas such as the Dining Area and Lounge that are supplied with a significant amount of supply air yet are un-occupied during the night. By installing zone isolation dampers, significant savings can be realized by restricting the supply air to areas that do require ventilation for significant periods of time.

Scope
A pair of zone isolation dampers will be installed in the 200mm and 225mm diameter ducts supplying the Lounge and Dining Room respectively. Variable Speed Drives (VSDs) will also be installed on the supply and return fans in order to maintain air balance in the facility. Both the dampers and the VSDs will be connected to the existing Johnson Controls – “Metasys” Building Automation System (BAS). Both dampers will then be programmed to open at 6:00am and close at 8:00pm. A push-button override will also be installed so that supply air can be provided outside the programmed schedule hours.

Kitchen & Laundry RTU Scheduling
Overview
The Arborfield & District Health Centre has two Roof Top Units (RTUs) serving the Kitchen and Laundry areas respectively. Each of the RTUs has a packaged D/X cooling system and a gas burner to temper ventilation air and is controlled by a thermostat located in each space. Currently each of these RTUs operates on a 24/7 basis. The Kitchen & Laundry spaces are largely unoccupied after 7:00.pm and 5:00pm respectively and as such significant savings can be realized by scheduling these units off during the unoccupied period

Scope
A programmable thermostat will be installed for each RTU and will be programmed according to the schedule shown in Table 5.6. The thermostat will have an override function to allow for extending the RTU schedule so that staff can activate each system to facilitate after-hours or on-call work. The RTU serving the Kitchen will also be interlocked with the operation of the Kitchen Range Hood so that the RTU and the hood will operate in conjunction with one another in order to maintain air balance in the space.

Boiler Flue Dampers
In the case of combustion appliances vented to the atmosphere, average standby time ranges from 85 to 90 percent if they are sized properly for their design loads. During this time, warm room air is drawn through the stack via the draft hood or dilution air inlet at a rate proportional to the stack height, diameter and outdoor temperature. More air is drawn through the vent immediately after the appliance shuts off and the flue is hot. When the combustion unit is not operating, a closed vent damper prevents residual heat from being drawn up the warm vent.

Electromechanical vent dampers will be installed on seven atmospheric boiler stacks. The electromechanical vent damper is coupled with the gas valve. For example, the vent damper will start to open on a call for heat. After a short delay of 15 to 30 seconds to ensure that the damper is open, the gas valve and ignition are activated. Conversely, the damper will close when the heat demand is met and the gas valve is closed.

Perimeter Radiator Reflectors
Overview
Wall areas, behind the perimeter steam radiators, are significantly hotter than other wall areas within the building. These hot areas transmit significant amounts of heat to the outside thus reducing the effectiveness of perimeter radiation.

Scope
Reflectors designed specifically for application on walls behind heating radiators will be installed to reflect energy back into the building space. In addition, the insulating pockets of air behind the heat reflectors further reduce heat losses normally due to convective and conductive
processes. These reflectors will greatly improve the effectiveness of the existing radiators, potentially allowing the heating loop temperature to be reduced and thus increasing the overall heating system efficiency and occupant comfort.

Vending Machine Control
Overview
Cold beverages are available for purchase at this site from a single refrigerated beverage dispensing machine. It has self contained refrigeration and illumination that are currently running constantly, regardless of whether people are in the area to purchase beverages.

Scope
A Vending Miser control will be implemented on refrigerated vending machines within the facility. It will be wall mounted and plugged into the receptacle providing power to the existing vending machine, and the vending machine will then be plugged into the Vending Miser receptacle. It can be relocated with the vending machine. A passive infra-red sensor detects occupants and allows the machine to power down when the surrounding area is vacant. The device also monitors room temperature and vending machine compressor operation to automatically re-power the cooling system at one to three hour intervals to ensure that drinks remain cool. Savings result because the machine lighting is only on when the area is occupied, and the compressor does not short cycle, which increases the efficiency and life span of the
compressor.

Parking Plug Control

Overview
Approximately 11 existing duplex parking plug receptacles are not presently controlled and are occupied approximately 80% to 100% during winter months. By implementing controls on these the power delivered to the plugs will be cycled based on outside temperature achieving both electricity consumption and demand savings while maintaining necessary power to the plugs so that users are able to start their vehicles. Time and temperature control will be installed. Plugs will be energized on at temperatures below -30C, alternate in at least 2-banks at 20 minute intervals at temperatures between -15C and -30C, and be off at temperatures above -15C. The lot will function as above to accommodate 24/7 function of the facility. Electrical savings will result from reduced energy consumption and reduced electrical demand.

Scope
IPLC controllers will be installed to replace the 11 existing duplex receptacles and programmed to cycle 40% of the time when the temperature is between -5C and -15C, 70% of the time between -15C and -25C and 100% of the time when the temperature is -25C or colder.

Building Envelope Sealing
Overview
An investigation to upgrade the current conditions of the building envelope was conducted by CANAM Building Envelope Specialist. The results of this investigation have uncovered several areas where the building envelope can be upgraded in order to reduce heating costs. Most of the areas where improvements may be made within the confines of the performance contract involve low cost sealing of identified cracks around doorways.

Scope
The scope of work detailed by CANAM recommends the weather sealing of 14 exterior doors and 1 interior door to the mechanical room

Backflow Prevention (VFA)
Overview
Backflow occurs when the water flows in the opposite direction from its normal flow. The cause of a backflow is a change in pressures. This reversed direction of water flow may allow contaminants to enter the drinking water system through cross-connections. Backflow Prevention is a strategy whereby a valve is placed in the domestic water supply line of a given facility in order to prevent contamination by pollutants due to ‘backflow’ in the system. Examples of testable backflow preventers used for medium to high hazard processes include: reduced pressure principle assemblies, double-check valve assemblies and pressure vacuum breaker assemblies

Scope
Backflow Prevention double-check valve assemblies will be installed in both the domestic and fire pump water supply pipes in order to comply with the 1995 National Building Code part 7.6.2.3 and CSA.Z317.1 Canadian Standards Association Special Requirements for Plumbing
Installations in Health Care Facilities, Section 6.3.3.5.