Mechanical System Mechanical System SelectionSelection

James Petersen, P.E.James Petersen, P.E.

Petersen EngineeringPetersen Engineering

Oracle at Delphi – Greek Oracle at Delphi – Greek MythologyMythology

gnōthi seautón = "gnōthi seautón = "know thyselfknow thyself““

mēdén ágan = "nothing in excess"mēdén ágan = "nothing in excess"

Oracle at the chicken coopOracle at the chicken coop

Painful LessonsPainful Lessons

SingleSingle Family Residence Family Residence

Neighborhood Boiler Neighborhood Boiler PlantPlant

Neighborhood Boiler Neighborhood Boiler PlantPlant

Student Housing Complex Boiler Plant

End of Painful LessonsEnd of Painful Lessons

DURABLEDURABLE

Castle Square, BostonCastle Square, Boston

Garden Apartments - 308 Garden Apartments - 308 UnitsUnitsMidrise Apartments - 192 Midrise Apartments - 192 UnitsUnits

Castle Square – Midrise Castle Square – Midrise UnitsUnits

Concept Midrise Systems Approaches Concept Midrise Systems Approaches 4-20-094-20-09

Heating & A/C ApproachesHeating & A/C Approaches Central Boiler, Perimeter BB, thru-wall A/CCentral Boiler, Perimeter BB, thru-wall A/C VRV air-cooled heat pump VRV air-cooled heat pump Heat pump – water-source Heat pump – water-source

Ventilation ApproachesVentilation Approaches Local Exhaust w Passive Inlet VentLocal Exhaust w Passive Inlet Vent Central Exhaust w Passive Inlet Vent Central Exhaust w Passive Inlet Vent Local HRV Local HRV Fresh Air to Heat Pump Fresh Air to Heat Pump

Domestic Hot Water ApproachesDomestic Hot Water Approaches As Is As Is New Heat SourceNew Heat Source Local ElectricLocal Electric

Final Midrise System Selection Final Midrise System Selection 9-4-099-4-09

Heating and Air-conditioningHeating and Air-conditioning Replace central boiler plant with high efficiency condensing boiler Replace central boiler plant with high efficiency condensing boiler

plantplant Reuse hydronic distribution pipingReuse hydronic distribution piping Replace unit baseboard and controlsReplace unit baseboard and controls Replace unit air-conditionersReplace unit air-conditioners

VentilationVentilation Provide new central exhaust fans with variable speed controlProvide new central exhaust fans with variable speed control Air seal existing central exhaust ductwork with “Aeroseal” duct sealing Air seal existing central exhaust ductwork with “Aeroseal” duct sealing

systemsystem Provide new exhaust grilles at kitchens and baths with modulating Provide new exhaust grilles at kitchens and baths with modulating

controlcontrol Install engineered passive inlet vents at all exterior roomsInstall engineered passive inlet vents at all exterior rooms

Domestic Hot WaterDomestic Hot Water Insulate existing hot water pipingInsulate existing hot water piping Integrate domestic hot water production with heating plantIntegrate domestic hot water production with heating plant Install solar thermal systemInstall solar thermal system

Castle Square – Garden Castle Square – Garden ApartmentsApartments

Concept Garden Systems ApproachesConcept Garden Systems Approaches 4-20-2009 4-20-2009

Heating & A/C ApproachesHeating & A/C Approaches Fancoil, 1 Boiler per 4 units, thru-wall A/C Fancoil, 1 Boiler per 4 units, thru-wall A/C Fancoil, 1 Boiler plant per building, thru-wall Fancoil, 1 Boiler plant per building, thru-wall

A/C A/C VRV air-cooled heat pump VRV air-cooled heat pump

Ventilation ApproachesVentilation Approaches Local Exhaust w/ Passive Inlet Vent Local Exhaust w/ Passive Inlet Vent Local HRV Local HRV Fresh Air to Fancoil Fresh Air to Fancoil

Domestic Hot Water ApproachesDomestic Hot Water Approaches As Is As Is New Heat Source New Heat Source Electric Electric

Final Garden ApartmentsFinal Garden Apartments System Selection 9-4-2009 System Selection 9-4-2009

Heating and Air-conditioningHeating and Air-conditioning Replace furnaces with fan-coilsReplace furnaces with fan-coils Reuse supply and return ductworkReuse supply and return ductwork Install one new wall-hung condensing boiler per four living Install one new wall-hung condensing boiler per four living

unitsunits Replace unit air-conditionersReplace unit air-conditioners

VentilationVentilation Add kitchen and bathroom exhaust fans, ducted to exterior Add kitchen and bathroom exhaust fans, ducted to exterior

brick vents/wall capsbrick vents/wall caps Add fresh air connection to furnace return air ductAdd fresh air connection to furnace return air duct

Domestic Hot WaterDomestic Hot Water Replace water heaters with indirect-fired storage tanks Replace water heaters with indirect-fired storage tanks

Old Colony, BostonOld Colony, Boston

116 UNITS (1000 UNITS OVER 10 YRS)116 UNITS (1000 UNITS OVER 10 YRS)

Old Colony, BostonOld Colony, Boston

Typical 1 Br Midrise Unit

Typical Townhouse Unit

335 Maplewood Ave335 Maplewood Ave

Project Blog: www.petersenengineering.com

Existing Proposed

DurableDurable

Questions?Questions?

james@petersenengineering.comjames@petersenengineering.com

www.petersenengineering.comwww.petersenengineering.com

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