MECHANICAL SYSTEMS AND EVALUATION

Description of Existing Systems

Heating Source

The main source for heating in the church buildings is steam purchased from the Board of Water and Light (BWL). There is a 6" steam main entering the building in the basement below the main church. This steam is then distributed throughout the building to air handlers, convectors, radiators, and also serves the domestic hot water system (except for the kitchen). Steam condensate is all gravity-returned to the basement and discharged through BWL condensate meters (Fig 33) to the sanitary system. These meters form the basis of the steam utility charges to the Church.

Heating and Ventilation Systems

Sanctuary

The Sanctuary is served by a steam heating and ventilating unit located in the basement. This unit is designed to supply tempered air to the sanctuary via duct shafts and grilles at each corner of the seating area. There is no apparent ventilation or heating delivered to the pulpit area. The return air to the unit is designed to be a mixture of return air from the space and outdoor air for ventilation. This is supposed to be accomplished through a damper arrangement on the main floor to the east of the main entrance. There are motorized dampers in the outside window and in the wall to the narthex. These dampers have been decommissioned and are set to a fixed position (outside closed, narthex open). The unit is not currently in working condition.

Additional heating is provided by steam convectors on each side of the seating area below the windows and by other convectors scattered around the perimeter of the sanctuary and balcony.

The original building design had accommodations for natural ventilation in the balcony. This vent was to be manually controlled to naturally exhaust heat from the ceiling area and outside through the attic. This vent has been closed and the louver in the attic remains open (Fig 38).

Chapel

There is a second air handler in the basement (Fig 21) that serves the Mary Sabina Chapel (Room 135). This air handler has steam heat and DX cooling. It is equipped with an outdoor air inlet duct which mixes with return air prior to the unit. The cooling coil (Fig 22) was installed in the return air duct downstream from the outside/return air mixing point. This unit delivers conditioned air through a duct chase to the chapel and return air is routed from floor grilles back to the unit. The condensing unit is located outside the east side. The steam coil was decommissioned.

The remaining classrooms on the first floor have only perimeter radiation with no ventilation. There are operable windows in most spaces so code does not require mechanical ventilation.

Lower Level Dining Room

The lower level Dining Room (Room B39) is served by a heating and ventilating unit (Fig 62). This unit is set up to manually control the amount of outside air and return air by moving a baffle to pass over or bypass a steam coil. The unit is not currently working.

Fellowship Hall

The Fellowship Hall (Room 118) is served by a small heating and ventilating unit installed in one corner of the main floor. In addition, the original building design allowed for natural ventilation through grilles located below the stage and a ventilation shaft to the roof. The shaft terminates on the roof with large hoods (Fig 35). The grilles have been removed and replaced with doors and the connection to the shaft has been boarded up. The hoods were originally designed for remote operation of dampers. This arrangement has been decommissioned.

Gymnasium

The gymnasium has perimeter radiation and operable windows. There is also a skylight with formerly operable vents for natural exhaust (Figs 34 and 39). Additional natural exhaust is available from under the seating area up to the roof. The Gym has perimeter radiators and a unit heater for winter heating if necessary.

Other Areas

Other rooms in the church buildings have perimeter heating (steam). Most areas also have operable windows, which can provide fresh air when opened. Stairways with exterior exposure have radiators or convectors.

There are window air conditioners in the second floor Pastor's office and the Music Director office 328.

Toilet Room Exhaust

Toilet room exhaust, where it existed, was typically connected to roof mounted exhaust fans. Exhaust draft was observed where grilles were installed. It's unclear how the exhaust fans are arranged and which toilet rooms were served. Some toilet rooms had no apparent means of exhaust (women's room B53, girls locker room 317).

Controls

Temperature controls, i.e. thermostats, dampers, etc., where they exist, are largely pneumatic. The source of the control air is a Dayton Speedaire compressor and small receiver tank.

Plumbing

The source of domestic water is a 2" main from the Board of Water and Light entering the building in the basement below the Chapel. Domestic hot water source is a steam heat exchanger (Fig 31) and two 119-gallon storage tanks (Fig 26), appropriately sized for the building. These serve all areas except the kitchen, which has a dedicated gas-fired water heater.

Toilet rooms have appropriate fixtures (water closets, lavs, urinals) that were observed to be in working order with a few exceptions. A few fixtures such as the first floor Mens Room urinal were noted to be not functioning.

Gas use is minimal – only to the kitchen appliances. Gas is metered outside and enters the building in the basement below the Chapel.

The Kitchen is equipped with dishwasher, two-compartment sink, garbage disposers, and exhaust hood over the range and oven.

Condition and Evaluation of Mechanical Systems

Mechanical Equipment

In general, the condition of the HVAC systems is fair to poor. The equipment is old and not functioning as intended with few exceptions. Specifically:

• The sanctuary air handler is not currently functioning, although a previous report commissioned by the church has indicated that an inspection was done completed and the report concluded that the unit is in good shape should restoration be undertaken.

• The chapel air handler has its heating coil disconnected, a result of a steam leak and consequent damage to the chapel. The cooling is operational and controlled from a thermostat in the chapel.

• The dining room unit ventilator is not controllable and would not run when switches were turned on.

• The Fellowship Hall unit ventilator was in working condition.

• The shower room exhaust fan in the boys locker room 315 was not working.

Ventilation Systems

Beyond the actual operation of the equipment, the building is lacking sufficient, reliable ventilation in almost all spaces. Areas where forced air equipment is installed do not have working outdoor air dampers. Areas where natural ventilation is designed have ventilation paths blocked. Specifically:

• The outdoor air/return air (OA/RA) mixing box in the Narthex for the Sanctuary air handler is completely disabled. The source of outdoor air to the air handler, the window, does not open. Consequently, the unit, when it was running, was only recirculating air.

• The outdoor air duct for the Chapel air handler is connected into the return duct before it reaches the unit. This will provide some OA/RA mixing, but it is not controlled and could not be determined whether the outdoor air louver was even open.

• The ventilation shaft from the two large roof hoods provides a natural ventilation path for the Dining Room and the Fellowship Hall. This path is blocked in each room not allowing any ventilation into those spaces.

• The vent shafts that serve room B40 are similarly blocked.

• The Gymnasium ventilation system is also not functioning. The hoods installed on the ends of the skylight are closed with the rope/pulley operating scheme missing. It's unknown whether the ventilation shaft from the area under the bleachers is functional. The gym does have operable windows on the south end, but these are generally blocked for protection.

• The Kitchen B28 has no means of make-up air for the hood except open windows.

• It was unclear whether there was adequate exhaust from the toilet rooms tied to exhaust fans. A tissue placed on the grille generally held indicating some measure of airfow.

• The only means of ventilation in the classrooms and childcare areas were operable windows.

Steam System

In general, the steam system is in good shape. With the exception of a few places, the piping is adequately insulated. The steam users are all trapped, but the condition of the traps is not known. Condensate flows freely through the meters. There is currently no condensate cooler which reduces the condensate temperature to 140oF as required by Code (MPC 803.1) before it dumps into building sewer.

The perimeter radiator and convector equipment seems to be functioning. The unknowns in this system are the steam traps. A steam trap 'purges' condensate out of the system, allowing steam to reach its destination in as dry a state/condition as possible to perform its task efficiently and economically. As steam traps age, their ability to maintain a seal between the steam and condensate systems deteriorates and steam is allowed to pass through the trap continuously. This causes waste and drives the cost of steam up. Traps that are leaking should be replaced.

In recent months, repairs have had to be made in the steam/condensate piping system to repair leaks. Couplings and/or fittings have been cut out and replaced. The point of failure was the threaded portion of the pipe – typical of very old threaded piping systems. The challenge doing an overall system evaluation is it would require destructive testing. In other words, pipes would have to be cut open in representative spots to determine the condition of the pipe.

Control System

The overall condition of the control system could not be determined within the scope of this report. The only active control devices are thermostats. A service contract with Quality Air has been used to review control devices and repair/replace as needed. Quality Air has maintained a job box in the basement and stocks devices and parts.

Plumbing

In general, the plumbing in the building was observed to be in good shape for the age of the building.

Building Code Issues

With respect to the ventilation issues, if a space is equipped with an operable window, it does not require forced ventilation. However, from a practical matter, occupant comfort and indoor air quality are dramatically improved by using mechanical rather than natural ventilation. Ventilation rates prescribed by ASHRAE Standard 62 cannot be assured by relying on open windows, particularly in the winter. Further discussion follows in the next section.

On the plumbing systems, the pertinent code concerns lie in the hot water temperature regulation. Current codes require mixing valves to prevent water too hot for human exposure from discharging through a lavatory or other sink. Proper use of mixing valves will allow water hot enough for dish washing (140F) to be used at the dishwasher, but will limit the temperature to 105-120F for other uses.

Energy code related considerations would be impractical to address overall in a building of this age. However, where recommendations address specific improvements, these measures will be compliant with current energy codes.

Constraints and Opportunities

Significant occupant comfort and indoor air quality improvements can be achieved in a number of ways ranging from new equipment and systems to restoring existing equipment and systems to a workable condition. It would be unreasonable from a cost perspective to consider air conditioning the building. Buildings of this vintage typically cannot accommodate the ductwork necessary for air conditioning. However, air conditioning could be added to significant portions of the building such as the Fellowship Hall and the Dining Room using rooftop equipment and utilizing the existing ventilation shafts for ductwork. The constraints on providing air conditioning would be electrical capacity.

A more practical approach would to be incremental steps to improve building ventilation. In a church environment, occupants are typically in the building for relatively short periods of time. Poor building ventilation causes hot spots and stuffiness that leads to discomfort. Eliminating these conditions through ventilation would improve the perception of comfort even if the actual temperatures were elevated. An overall improvement can be accomplished by:

• Restoring the ventilation shafts and roof hoods, retrofitting with appropriate controls.

• Replacing the Sanctuary air handler and restoring the outside air/return air controls.

• Adding outdoor air controls to the Chapel air handler.

• Restoring the ventilation operation of the Gymnasium skylight and under-seating area.

• Restoring a means to exhaust heat from the upper areas of the Sanctuary, particularly the balcony.

• Providing positive ventilation for the Dining Room.

Published data indicates the average annual energy costs for a church in this part of the US is between $0.48 and $0.68 per square foot. Other metrics have the average energy usage at 53,000 BTU/sq.ft./year. Based on energy bills for the past year, Central UMC spends and utilizes:

Utility Cost BTU

Steam $ 24,580 4,691,250,000

Electricity 7,729

Gas 869

Total $ 33,178

Total Sq.Ft. 63,120 63,120

Per Sq.Ft./Yr. $0.53 74,323

This suggests there are opportunities for energy conservation measures (ECM). ECM's such as lighting retrofits have quick paybacks yielding energy savings that could potentially provide a means to fund other improvements. While a comprehensive energy evaluation is beyond the scope of this study, it's quite possible that some of the following can provide positive opportunities:

• Lighting bulb and ballast retrofit

• Insulation on steam lines

• Steam trap study

• Domestic water heating with gas instead of steam in some areas

The room that houses the main organ workings must be maintained at a constant temperature and humidity. While the temperature and humidity have no exact requirements, the workings are susceptible to rapid changes. Currently there is a humidifier in the space.

Specific Recommendations and Cost Summary

The following recommendations are to be considered by the church. These address both code and comfort issues. Implementation of these recommendations can be challenging and maintenance of systems is necessary to sustain the results. Estimated cost of implementation is found on summary tables.

In general, It is recommended that the church develop a service relationship with a local mechanical contractor who can offer on-going service and preventative maintenance. This would remove the irregular nature of maintenance and afford continuity and expertise in mechanical systems.

Implementation of any recommendation involving the ductwork in the basement of the original church would be subject to asbestos abatement. The existing duct insulation is undoubtedly asbestos and should be removed and replaced with new insulation. Costs for this would be outside the scope of the mechanical contractor

Specific recommendations are:

M-1 Sanctuary Ventilation – First and foremost, the heating and ventilating unit in the basement should be restored with new controls to provide ventilation air to the sanctuary. This unit is capable of providing constant ventilation into the sanctuary through existing ducts. The outdoor air/return air arrangement in the south window area can be restored to allow outdoor air to enter the unit. The amount of outdoor air can be controlled by return air CO2 in order to save energy during times of low occupancy.

This would require an overhaul of the unit controls, reconstruction of baffles and new damper controls in the window area, cleaning of ductwork between the unit and the seating area, and new thermostat controls for heating.

M-1A Sanctuary Air Conditioning – In addition to the above, to add air conditioning to the unit would require the installation of a cooling coil to the unit, condensate drainage, condensing unit, and refrigeration lines. The existing ductwork could be re-used, but would have to be modified in the sanctuary and special diffusers would be installed for proper air distribution and mixing. The condensing unit would have to be installed in the Ottawa Street parking area, taking up one parking space.

M-2 Chapel Ventilation – Again, ventilation can be improved by adding mixed air damper controls to the outdoor/return air ducts. This can also be controlled by CO2 for energy savings. This unit should be replaced with a new furnace (or air handler)/condensing unit split system for air conditioning. Heating would be gas-fired. Factory mounted controls can simplify the operation and reduce the control devices now installed.

M-3 Fellowship Hall/Dining Room Ventilation – Natural convection would not provide sufficient ventilation to either the Fellowship Hall or the Dining Room to meet current codes. These spaces can be considered together for a number of reasons. There is a ventilation shaft that joins these areas with the roof. A heating and ventilating unit can be installed on the roof that would furnish the necessary ventilation to the spaces below. Depending on the normal operation of the church, the unit could be sized to handle both spaces at once, or, sized to handle either space but not both. The unit would be gas-fired heating to temper the ventilation air in the winter and would have CO2 controls to regulate the amount of ventilation.

M-3A – Fellowship Hall Air Conditioning – The Fellowship Hall could be air conditioned by adding cooling to the unit mentioned above and installing distribution ductwork along the balcony. This ductwork would be boxed in and finished for appearances. The ventilation shafts would be used for ductwork to and from the roof. If selected, the ventilation for the Dining Room would have to be modified from what was proposed above.

M-4 Ventilation in Sanctuary Balcony – Heat rising to the upper balcony in the sanctuary should be exhausted, either naturally or mechanically. Using a mechanical solution, a fan could be installed in the attic space with a new grille in the ceiling of the balcony. The discharge of the fan would be tied to the existing louver on the exterior wall and the ductwork between the fan and the ceiling grille would be routed through the attic and lined with acoustical insulation to prevent fan noise from disturbing the occupants

M-5 Repair Dining Hall Air Handler – If a general space ventilation scheme is not implemented the existing air handler, if repaired and restored to working order, would allow some measure of ventilation into the space. It could remain manual whereby the ventilation air would be diverted across the steam coil or introduced directly into the room, depending on the position of the manual damper. This equipment is old but could be brought back into service with minimal effort.

M-6 Repair Gym Ventilation – The gym heat relief dampers could be repaired and restored in a more user-friendly form. Electric motors and dampers could be installed to open the dampers automatically upon a rise in temperature, or through manual initiation of the damper motors. This could be coordinated with the wall damper/louver to allow a path of natural ventilation and heat relief.

M-7 Add exhaust fan at roof and inlet under seating in Gym – As an alternative to natural ventilation for the gym, an exhaust fan could be added to the roof monitor and be controlled to remove heat at the ceiling. This could be coordinated with the stack and roof inlet that is routed under the seating area. New dampers would have to be added to the inlet and controls would be installed.

M-8 Add exhaust fan to T/R 353 – The women's toilet room 353 currently has no means of ventilation or windows. A new exhaust fan should be installed discharged outside.

M-9 Repair boys shower room exhaust fan – The existing fan should be repaired or replaced.

M-10 Install new exhaust fan in girls shower room – A new fan should be installed in the girls shower room to provide adequate ventilation and exhaust or moisture.

M-11 Kitchen make-up air – The current kitchen hood has not mechanical make-up air which is now required by code. This would have to be done using a pad mounted make-up air unit outside the windows. Ductwork would have to be run exposed and enter the kitchen through the window.

M-12 Steam trap study – As an energy savings measure, a steam trap study should be started and a trap repair/replacement program should be considered. The study could be provided at a nominal cost and would give the church a clearer picture of the steam system and the potential for steam cost savings.

M-13 Sample test steam piping – If a clearer picture of the steam and condensate piping was desired, the church could work with a mechanical contractor to identify any likely areas of potential pipe failures and have sections of the piping cut out and replaced. This would reveal the condition of the pipe and an assessment of potential failures could be clearer.

M-14 Organ Room – Due to the critical nature of the ambient environment in the room that houses the organ workings, we propose a precision air conditioning unit, one similar to that installed in a computer room, be installed in the space. This would allow the space to be maintained at a constant temperature and humidity. Space for a condensing unit would be found either on the roof or on grade.

Mechanical System Issues

Number Priority Item Cost Comment

M-1 High Sanctuary Ventilation $15,000

M-1A Medium Sanctuary Air Conditioning $50,000 In addition to M-1 costs

M-2 High Chapel HVAC $10,000

M-3 High Fellowship Hall/Dining Room Ventilation $25,000

M-3A Low Fellowship Hall Air Conditioning $10,000 In addition to M-3 costs

M-4 High Sanctuary Balcony Ventilation $5,000

M-5 High Repair Dining Room Air Handler $5,000

M-6 Medium Repair Gym Ventilation $3,000

M-7 Medium Add Exhaust Fan to Gym Roof Vent $2,000

M-8 High Add Exhaust Fan to T/R 353 $1,500

M-9 High Repair Boys Shower Room Exhaust Fan $1,500

M-10 Low Install new Exhaust Fan in Girls Shower Room $2,000

M-11 Low Add Kitchen Make-up Air Unit $15,000

M-12 High Steam Trap Study $4,000

M-13 Medium Sample Test Steam/Condensate Piping $500

M-14 High Add HVAC to Organ Room $5,000


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