CHAPTER 8 Mechanical Systems and Insulation Electrical Service

CHAPTER 8 Mechanical Systems and Insulation

Electrical Service Entrance Cable � This is a cable located outside a house � It provides electricity service through underground or overhead wires from the road to the structure � It typically provides 240 Volts electricity from the street supply ◦ The size of the entrance cable controls the amount of electricity that is available

Electric Service Size � Electric service size describes the number of amps that are provided to any structure through a primary wire service � Once the power enters a structure, it travels to a main disconnect with 2 circuit breakers or fuses ◦ One fuse is for the negative black wire while the other is for the positive red wire ◦ Fuses are rated according to the amperage that the wire can carry safely (e. g. 60 amps / 100 amps etc. ) � Service cables size is determined by the thickness of the

Distribution Panel � Distribution panels are electrical panels that are located between service entrance wires and power distribution in any structure � It acts as an interface and is connected by service wires to the main disconnect � Types of distribution panels: 1. Knob and tube (old system, prone to fire, results in high insurance premiums) 2. Circuit breakers (new industry standard, safer and cheaper to insure) � Some properties in downtown Toronto still have knob and tube distribution panels

RECAP � What type of electricity distribution is more expensive to insure and most prone to fire? ◦ Knob and tube � What is the name of the distribution panel type that replaced knob and tube? ◦ Circuit breakers

Electricity Main Disconnect � An electricity main disconnect switch provides people with the option to shut-off-all power in a structure ◦ It is the main power switch for a structure � Switch handles are typically located outside the structure while breakers or main fuses are located inside the main structure � Hydro authorities frequently seal covers onto the main disconnect so that only they are able to access it

Grounded Outlets �A grounded outlet is the third ground wire ◦ It does not conduct electricity ◦ It grounds excess electricity ◦ It acts as a safety measure � Grounding is a process by which electricity is diverted to the ground � Positive wire = red/white, negative wire = red, ground wire = copper/green

RECAP � What color is the ground wire? � What is the function of the grounded outlet? ◦ The grounded outlet wire is green ◦ It grounds excess electricity or bypasses electricity to the ground

Heating Systems � Heating warm � There 1. 2. 3. 4. 5. systems are used to keep structures are several types of systems: Steam Warm air Radiant Electrical Hot water

Furnaces � Furnaces are central heating systems that generate heat in one location and distribute it to different parts of the structure ◦ Distribution normally happens through sheet metal ducts � All furnaces except electric furnaces have: 1. Heat Exchanger 2. Burner 3. Blower

Furnaces � Electric furnaces have heating elements/coils � Convection cold is the movement caused by hot and ◦ Cooler gasses are more dense and they sink because of gravity ◦ Hotter gases are less dense and rise because of gravity ◦ This movement results in the transfer of heat � Convectional burning gas refers to heat generated by coils or ◦ It is distributed through structures by a fan

� Types Furnaces of furnaces 1. Electrical furnace �Does not rely on actual combustion, which means it does not have a chimney, burner or heat exchanger �Instead, it has heating elements �Blower forces air across heating element to warm air, and the air is circulated in the home through ducts 2. Gas furnace �Four types 1. 2. 3. 4. Convectional Mid-efficiency High-efficiency pulse

Furnaces 3. Gravity Furnace/Octopus Furnace �Function the same way as a convectional furnace but do not have a fan to blow air through the ducts �It uses convection (gravity) to circulate hot air �It has 8 pipes going to 8 different rooms which is why it is called Octopus Furnace �Pipes carry hot air, which rises as cool air sinks to the ground �Cool air returns to furnace through an inlet �These furnaces are obsolete because of their high level of inefficiency 4. Oil Furnace �Similar to gas furnace �Oil must be stored on site to operate it

RECAP � What is the main difference between a conventional furnace and a gravity furnace? ◦ A gravity furnace does not have a fan � Which furnace type has a radiator? ◦ Convectional furnace � What kind of furnace is a gas furnace? � What is an octopus furnace? ◦ Convectional ◦ A convectional and gravity furnace

�A Boiler boiler is a heating system that generates heat in one location and distributes it through pipes to other locations in a structure ◦ They are made up of open and closed systems � Hot water systems do not boil water but heat it to a maximum of 160 degrees Fahrenheit � Boilers have two primary components: 1. Heat exchanger which contains natural gas or oil on one side and the water that will be heated on the other 2. Boiler

� Types Boiler of boiler systems 1. Closed-boiler system �Does not have overflow expansion pipe or tank �It is industry standard these days �Has circulating pump that forces water throughout home pipe system 2. Open-boiler system �Has overflow expansion pipe or tank �Old system that has been discontinued �It requires expansion tank which is typically placed above the highest radiator in a structure �This tank allows for expansion when the water is heated �It does not require a pump since it makes use of gravity

� HVAC = “heating, ventilation and air conditioning” ◦ It is a heating/cooling system used in commercial buildings typically mounted above ceilings ◦ It ensures even distribution of fresh air, heating and cooling throughout a structure � HVAC has the following components: 1. Air handler = series of fans that moves air 2. Ductwork = ducts transport air through structure 3. Condensing unit = compresses the Freon gas that is used to cool air; is placed outside the structure 4. Roof Top HVAC = mounted on roof of structure

Chimney � Chimneys are vertical structures that contain a single or multiple flues that help discharge smoke/gases from a furnace or fire � Chimneys are no longer required and are often removed till they are below roof-level during re-roofing ◦ This means you don’t have to worry about maintaining them ◦ It also reduces risk of water leakage from chimney flashing (see flashing)

Chimney Flue and Cap �A flue is a distinct and separate channel that allows for smoke in the chimney �A cap is a structure above the chimney that prevents water from entering it

� Classes Drainage Systems of drainage systems 1. Class 1 – no tank �Waterless toilets with pit; found on construction sites 2. Class 2 – no tank �Can only be used for non-human waste, called greywater system 3. Class 3 – no tank �Uses cesspool, similar to class 2 but used for human waste 4. Class 4 – has a tank �Private drainage system that is common in rural areas, called leeching bed system 5. Class 5 – has a tank �Holding tank, not private drainage system �Emptied by collection company

Drainage Systems � Class 4 and 5 are used in rural and recreational areas � Class 4 system includes: 1. Septic tank – which has bacteria that eats/decomposes waste 2. Leeching bed – filter with holes surrounded by filter materials such as sand

Drainage Systems � Types of leeching beds 1. Conventional Leeching Bed �Most common �Installed where land well-drained and bed can work using stone-filled trenches dug below ground level �Water is allowed to leech back into ground water, filtering through various layers of ground 2. Raised �Second most common �Used where landscape doesn’t allow for self-filtration �Filtering materials are brought onsite and a raised bed is made for stone-filled trenches

Drainage Systems 3. Filter � Used only when space is limited � The entire bed is excavated and filled with special filtering sand that allow for closer pipes within the bed � ◦ Class 5 Holding Tank It is the porta-potty system where tank periodically emptied by waste removal services

RECAP � Class 4 septic tank system is a private drainage system � Class 4 septic tank system consists of an absorption bed or leeching bed � Class 4 septic tank is a treatment tank

R-2000 � R-2000 is an energy efficiency program pertaining to the construction of new homes � It sets performance standards that are more stringent than those stated in Building Codes � It is the most energy efficient construction designation and includes all things energy efficient, such as solar panel roofs and CSA standard windows