22-Mec-B2 Environmental Control in Buildings
Worked solutions to 13 past sittings (2013–2019), 104 questions. Pick a sitting, or start from a topic below.
- December 2019
- December 2018
- May 2018
- December 2017
- May 2017
- December 2016
- May 2016
- May 2015
- December 2014
- May 2014
- December 2013
- May 2013
- Undated paper
Topics across the sittings
Topics that come up in more than one sitting, taken from the headings of our worked solutions. A topic counts once per sitting.
- Preheat (5 sittings): December 2018 Q2 · May 2017 Q1 · December 2013 Q1 · May 2013 Q2 · Undated paper Q3
- Reheat (5 sittings): December 2018 Q3 · May 2018 Q1 · May 2017 Q1 · May 2016 Q2 · May 2013 Q2
- Cycle (4 sittings): December 2019 Q5 · December 2017 Q1 · May 2015 Q1 · May 2013 Q1
- Apparatus dew point (3 sittings): May 2016 Q8 · December 2013 Q2 · Undated paper Q1
- Indoor air quality (3 sittings): December 2017 Q5 · May 2015 Q4 · May 2014 Q7
- Mixing (3 sittings): December 2018 Q3 · May 2016 Q2 · December 2013 Q1
- Stack (3 sittings): December 2019 Q7 · December 2014 Q7 · Undated paper Q5
- Steam humidifier (3 sittings): December 2016 Q2 · December 2014 Q2 · Undated paper Q3
- Summer plant (3 sittings): December 2018 Q3 · May 2016 Q8 · Undated paper Q1
- Thermal comfort (3 sittings): May 2018 Q8 · May 2017 Q5 · December 2013 Q7
- Adiabatic saturation (2 sittings): December 2018 Q2 · May 2013 Q2
- Annual heating (2 sittings): December 2018 Q8 · May 2013 Q4
- Cavity wall with a window (2 sittings): December 2016 Q6 · May 2015 Q5
- Chilled-water reset (2 sittings): May 2017 Q5 · May 2013 Q7
- Coil capacity (2 sittings): May 2016 Q8 · December 2013 Q2
Questions by sitting
December 2019
- Question 1: All-outdoor-air operating-room plant — state points, air quantity, coil duty
- Question 2: Induced-draft cooling tower — air flow at the fan and make-up water
- Question 3: The self-sustainable house — definition, construction and building systems
- Question 4: Composite wall with a plaster thermal bridge; moisture flow and vapour barriers
- Question 5: Ground-source heat pump on R-134a — cycle, COP, refrigerant flow and running cost
- Question 6: Degree-day estimate for a Winnipeg building — gas quantity, relative cost and primary energy
- Question 7: Dilution ventilation for an indoor NO x source; stack and wind pressures on a tall building
- Question 8: Duct sizing for equal branch friction, and the effect of hot low-pressure air
December 2018
- Question 1: Composite wall — total resistance, heat loss and the controlling layer
- Question 2: Preheat, adiabatic saturation and reheat on 100% outdoor air
- Question 3: Summer plant — mixing, chilled-water coil, reheat and plant energy
- Question 4: R-134a refrigeration plant — COP, mass flow and compressor size
- Question 5: Cooling load of an east-facing office at 15:00 in July
- Question 6: Two-branch duct system balanced against the fan characteristic
- Question 7: Energy-efficient high-rise office design, and LEED certification
- Question 8: Annual heating and cooling energy and cost for a Toronto office
May 2018
- Question 1: Summer plant with cooling coil, reheat and a face-and-by-pass rebuild
- Question 2: Condensation on the walls of an enclosed balcony
- Question 3: Terminal reheat and VAV with discriminator control
- Question 4: Ground-water heat pump with R-134a
- Question 5: The zero net energy building
- Question 6: Equal-friction duct design for a conference centre
- Question 7: Design heat loss from a Toronto conference room
- Question 8: Carbon dioxide dilution and thermal comfort
December 2017
- Question 1: Summer air-conditioning plant — cycle, load and energy input
- Question 2: Winter heating and humidification plant — preheater rating and washer efficiency
- Question 3: Induced-draft counter-flow cooling tower
- Question 4: Ammonia cold-storage plant for a milk chilling duty
- Question 5: LEED certification and indoor air quality
- Question 6: Overall U factor of a curtain wall with 40% glass
- Question 7: Centrifugal fan selection from a manufacturer’s table
- Question 8: Seasonal gas consumption of an R-2000 house and the value of night setback
May 2017
- Question 1: Winter heating and humidifying plant — preheat, adiabatic spray, reheat
- Question 2: Summer cooling and dehumidifying plant — mixed state, coil duty, ADP and by-pass factor
- Question 3: Induced-draught counter-flow cooling tower
- Question 4: Two-stage ammonia plant with a flash chamber
- Question 5: Thermal comfort, chilled-water reset and campus cogeneration
- Question 6: U-factor of a 2 × 4 stud wall, and mould on an uninsulated solarium wall
- Question 7: Round duct sizing by the equal-friction method
- Question 8: Internal heat gains at 4 p.m., and seasonal gas use by the degree-day method
December 2016
- Question 1: Summer air-conditioning plant for a department store
- Question 2: Winter plant with preheater, furnace and steam humidifier
- Question 3: Annual energy and running cost by the degree-day method
- Question 4: R-22 vapour-compression heat pump
- Question 5: Five concepts in sustainable building services
- Question 6: Cavity wall with a window, and moisture flow through walls
- Question 7: Fan energy, and duct pressure loss
- Question 8: Hourly cooling load by the CLTD / SCL / CLF method
May 2016
- Question 1: Seasonal heating fuel, and a gas furnace against an air-to-air heat pump in Winnipeg
- Question 2: Winter plant with preheat, mixing, reheat and steam humidification
- Question 3: Ventilation and infiltration heat loss, and the effect of attic ventilation on ceiling loss
- Question 4: Equal-friction duct sizing and system pressure loss
- Question 5: Induced-draft counterflow cooling tower
- Question 6: Two-stage R-134a plant with a flash chamber and a direct-contact intercooler
- Question 7: Comparing heating and cooling options for a downtown hospital
- Question 8: Summer plant — supply air, coil capacity, apparatus dew point and bypass factor
May 2015
- Question 1: Mixed-air plant with reheat — cycle, plant loads and energy input
- Question 2: Winter heating cycle with a steam humidifier
- Question 3: Centrifugal fan power and the fan laws
- Question 4: Indoor air quality — controls and standards, and a dilution-ventilation calculation
- Question 5: Cavity wall with a window — the window's share of the heat loss
- Question 6: Induced-draught cooling tower — leaving water temperature and make-up rate
- Question 7: Seasonal heating fuel, and a gas furnace versus an air-source heat pump
- Question 8: Ideal R-134a vapour-compression chiller, and refrigerant environmental concerns
December 2014
- Question 1: Summer air conditioning of a clothing store
- Question 2: Winter plant with heating coil and steam humidifier
- Question 3: Equal-friction sizing of a perimeter duct branch
- Question 4: Internal heat gains and a degree-day fuel estimate
- Question 5: Office heat loss, and moisture flow through wall structures
- Question 6: Refrigerant selection and plant strategy for a 1970s hospital chiller
- Question 7: Stack and wind pressures and infiltration in a 20-storey tower
- Question 8: Water-source R-134a heat pump
May 2014
- Question 1: Summer cooling plant with a governing ventilation rate
- Question 2: Winter preheat, humidify and reheat plant
- Question 3: Fan laws, duty point and throttling
- Question 4: Degree-day comparison of gas, electric and heat-pump heating
- Question 5: Ventilation, infiltration and attic ventilation
- Question 6: Summer cooling load method; sheathing thickness and vapour control
- Question 7: VAV systems and indoor air quality
- Question 8: R-134a air-source heat pump
December 2013
- Question 1: Natatorium — mixing, preheat and psychrometric cycle
- Question 2: Summer air conditioner — apparatus dew point and coil capacity
- Question 3: R-134a heat pump — COP, displacement and running cost
- Question 4: Tall-building infiltration — stack effect, wind and door traffic
- Question 5: West window solar heat gain and the infiltration load expression
- Question 6: Perimeter duct branch sized by the equal-friction method
- Question 7: VAV systems, CO 2 -limited occupancy and thermal comfort
- Question 8: Transmission heat loss through a frame dwelling wall
May 2013
- Question 1: Mixed-air plant with reheat — cycle, loads and plant energy
- Question 2: All-outdoor-air winter plant — preheat, adiabatic saturation and reheat
- Question 3: Two-stage ammonia refrigeration with a direct-contact intercooler
- Question 4: Annual heating and cooling energy and cost for an Ottawa office
- Question 5: Duct design methods and static-regain sizing
- Question 6: Mechanical-draught cooling tower — leaving water temperature and make-up
- Question 7: Carbon-dioxide dilution, the ASHRAE comfort chart and chilled-water reset
- Question 8: Parallel-path U-factor of a stud wall, and mould on an uninsulated concrete wall
Undated paper
- Question 1: Summer plant — mixing box, cooling coil, apparatus dew point
- Question 2: Interior office heating load; net-zero energy buildings
- Question 3: Winter plant — preheat, mix, heating coil and steam humidifier
- Question 4: Ground-source R-134a heat pump
- Question 5: Stack and wind pressures, and infiltration, in a 10-storey building
- Question 6: Equal-friction duct sizing
- Question 7: Annual heating cost by the degree-day method — Ottawa
- Question 8: Instantaneous heat gain through a west-facing double-glazed window