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355 Study Guide Prelim 1
Financial Measures, Trends and Asset Management
Building Maintenance (all from an operating budget) Initial Investment (development, construction) Routine Maintenance (upkeep, routine: vacuuming, window cleaning) Preventive Maintenance (preventing bad things from happening: filter changes, cleaning refrigerator coils) Scheduled Maintenance (takes longer, more complex: swimming pool) Emergency/Breakdown Maintenance (worst case at the worst time) o Deferred Maintenance (waiting till the last minute; more expensive later) Renovation/Rehab (big change, expensive)
Asset managers = increase NOI (net operating income), maximize the value of property, from acquisition through sale, within the objectives of the owner. Revenue – Operating Expenses = CapEx. NOI = income after operating costs and fixed costs (doesn’t include depreciation, amortization, or debt service) To improve NOI, increase revenue or decrease costs
2 Cost Categories:
- Property Operation and Maintenance Costs (POM or R&M) – For hotels this is usually 5.1% of gross revenues. For restaurants, usually 1.5-1.8% of gross revenue.
- Utilities Costs – Usually 5.1% of gross revenue for hotels and 2.5-3.5% of gross revenue for restaurants.
How is CapEx obtained? Bargain between owner and Management Company. Reserve for Replacement = the owner will take a % of gross revenue and set it aside. Usually 3-5%; oftentimes 7% is what it should be. Newer building = lower percentage.
Owner/Investor Portfolio Manager Asset Manager Property Manager
Owner’s long-term objectives: Long-term appreciation – influenced by market, building/space market value will increase Hedge against inflation – by real estate now so you won’t have to pay more of it later Protection against currency changes – when the dollar is down, foreign countries buying property Portfolio diversification – smoother ROI. Domination niche market. Contrarian (vulture fund), social responsibility (urban revitalization), and EGO investor (trump)
Emergency Disaster Planning
What is an emergency = “a situation, often dangerous, which arises suddenly and calls for prompt action. An immediate need.” What is a disaster = “an event causing great loss, hardship, or suffering to many people. A great or sudden misfortune.”
Different types of emergencies and disasters: Natural – hurricane, snow, rain, wild fires, locusts, mudslides, meteors, sinkholes… Human-created – Terror attacks, pollutants, chemical leaks, arson (man-made fire) …
Four stages of an emergency/disaster:
- Mitigation – to make less severe Identify all possibilities and probabilities Minimize damage Develop plan of action Disseminate the plan to everyone Practice (fire drills) Adjust and fine-tune
- Preparedness – you know its coming (hurricane) Cleaning and preparing building Emergency supplies and equipment on site 1 st-aid equipment Building address is clearly posted Emergency info. Cards
- Reaction/Response Do what you planned to do Contract outside help (fire department, police..)
- Recovery Saves lives and protect injuries Clean-up & salvage Insurance company (written documentation, photo, video…)
Why we should have an emergency and disaster preparedness plan – to better handle any situation. Sarbanes Oxley legislation –corporate financial scandals Business Continuation Planning (BCP) – in the event of a disaster, the company can continue to go on so employees don’t lose jobs (data back up, emergency and disaster planning)… like Sonesta employees at Royal and Chateau during Katrina.
Elements of a good plan: Incident response team – must have a spokesperson (to media) Facility Data Document – building’s address, phone number, contact information for incident response team, insurance company, location of building components Communications with the outside supporting agencies (fire department, police, red cross, FEMA, homeland security) List of current vendors – electrical contractor, roofer, plumbing contractor Action plan with step-by-step instructions: o Specific procedures for specific types of emergencies (preparedness) o Post-incident Plan (is business disrupted? If yes, Notifying employees) – EE (employee) incident debriefing (crime or medical), community communications, identify and retain records.
Supplier market – no control over costs. If they dump illegally, both companies are responsible. How do we get billed? Tipping fees (number of tips/trips, weight or volume) How can we reduce tipping fees? Decrease weight, decrease volume, decrease number of tips/trips
Reduce * Reuse * Recycle * Transform * Pulp
Reduce: Source Reduction. Simply reduce the amount of garbage generated in the first place. Examples: ceramic cups vs. Styrofoam, reduce packaging, inventory control (perishables), notes on computer and not on paper. ** This is not the same as recycling to divert garbage from a landfill
Reuse: Purchase supplies in containers that can be refilled by supplier or by you. Examples: rags, kegs, condiment, fountain drinks.
Recycle: Take materials that can be broken down (mechanically, chemically) and use to make new items. “A series of activities that includes collecting recyclable materials that would otherwise be considered waste, sorting and processing recyclables into raw materials such as fibers, and manufacturing raw materials into new products.” (US Environmental Protection Agency). Examples: paper, cardboard, glass, metal, plastics, yard waste recycling (compost), food waste recycling (turn it into compost or pig feed). ** You are not truly recycling if you are not buying recycled products.
Transform (waste): Incinerating waste. Burning garbage is not good for the air quality. Can’t put one in business, not worth the investment.
Pulping: grinding food waste, extracts water (video in class of pulping at Appel)
Hazardous Materials – storage, use and disposal MSDS sheets – Material safety data sheets (instructions for every chemical). Mandated by OSHA and EPA (Environmental Protection Agency) EPA audits – Comes to property to see if you abide by the MSDS sheets. Oftentimes initiated by employee complaint.
Typical hazardous materials found in hospitality facilities: chemicals, PCBs (carcinogens), grease/fat, septic system waste, used batteries, bio-hazards (blood-borne pathogens, biological substances).
All need to be handled according to regulations or your business can be subjected to: heavy fines, civil and criminal prosecution, really bad publicity, lawsuits by employees or others affected by the materials.
Mold, Asbestos, Lead, and LEED
Mold A living organism that feeds on organic material in a warm, moist environment. Most mold is not harmful, but icky. Some is harmful: aspergillus, stachybotris, and “black mold.” Find it anywhere where it is warm, dark, and damp. We worry about the toxins (some spores are highly toxic) which
cause flu-like symptoms. It needs to be cleaned and removed. If there is a small infestation (10 sf), clean it yourself. Otherwise, remediation for more serious jobs.
Procedure for fixing a mold infestation : Look for the extent of the infestation, find source of moisture and fix. If there is a large infestation, get it tested by a professional. If it is “bad mold,” need to find a qualified remediation contractor – must be legally disposed of Seal off the area (guestrooms out of service) and part or all of the building must be shrouded in polyethylene (plastic) Qualified workers in isolation suits and respirators This is time consuming, messy, and expensive.
Asbestos A naturally occurring mineral with excellent durability, acoustical and insulating properties. Excellent for fireproofing (prevents fires). It is also found in pipe insulation (boilers), equipment insulation, vinyl floor tiles (VATs), acoustic ceiling tile, drywall, automobile brake pads. If fibers from the mineral break off and are airborne, they can be inhaled and lodge themselves in the lungs. Known association with lung diseases, such as asbestosis and cancer. Dangerous when “friable” – this is when the asbestos is crumble or breaks off easily and can be pulverized with your hand. What needs to be done? Remediation and encapsulation!
Procedure for fixing an asbestos infestation: Be vigilant if building was built before 1980 If you have friable asbestos, you need to remediate or encapsulate If it’s in a place where it won’t be disturbed, it can be encapsulated (or securely covered) If it’s friable and will be disturbed, you must have it removed and disposed of by a quailed contractor. Disturbance can include: getting hit and chunks falling off, sanding, cutting/sawing, grinding, these often happen while you are replacing equipment or doing renovations. Need to assess your project thoroughly before beginning work. Expensive, messy, and time-consuming
Lead This is a naturally occurring element (more serious than asbestos and mold) that has been used for thousands of years, primarily in plumbing and paint. It was prohibited as a component in paint in the 1970s. Current plumbing fixtures still contain small amounts of lead, but you should not be exposed to it. Water supply system (from city or municipality) probability has some lead in the pipes and seams. Older buildings have lead in the paint (which may be covered up by more recent coats of pain) and in the plumbing system. It is toxic to humans (and animals), affecting bones, blood, and organs. It is a cumulative and is stored in the bones, displacing calcium. It will release slowly into the body over time and destroy blood cells, injure organs, and cause brain damage. It can mess up your central nervous system and make your bones brittle.
Procedures for fixing a lead infestation: Encapsulation or removal Both should be don’t by certified professionals only (certification includes scheduled testing of lead exposure levels in the blood)
ROI is 25-40%
Operating costs savings of: Energy: 30% Water use: 30 – 50% Waste cost: 50 -97%
Productivity increases: Hospitals: 2.5 day earlier discharge Schools: 20% better test performance Retail: increased $/sq ft Offices: 2 – 18% increase in productivity
What you might not hear: Initial Costs:
The certification process itself can be expensive (fees for filing paperwork & inspections)
Actual financial impact on project ranges from 1% -- 10% premium (depends on level of
certification and building type)
The paperwork can be onerous
Construction:
Hard to find qualified contractors who will do the LEED-certified work
Need to train construction workers to not take short-cuts that defeat LEED goals
Operating the Building, Post-Occupancy:
LEED – NC has to be recertified as LEED – EB periodically to retain certification
Savings realized (which impact your certification) vary greatly by location, due to
weather differences and local energy costs
Operating a LEED building can be tricky – need to find technicians who are trained
on specialized/state-of-the-art equipment
Water Systems – Water Supply and Wastewater Disposal Systems
Flow pressure – measured in pounds per square inch (psi). Flow volume – measured in gallons per minute (gpm). Aquifers – large deposits of water that lay deep undergrouand.
Water Supply Systems – two types Constant Pressure Systems (low rise, low volume). Water supply, pump from bottom to each floor. Pressure is used to fill each fixture. This is adequate for most small applications without excessive water use. Gravity-fed Systems (high rise, high volume). Water supply, pumps used to storage tank on top of the building. Gravity pulls water down to each floor. No suction, just water right. Some hotels might put another tank in the middle of the property.
Wastewater Systems: Two major systems for removing water from the property Storm Sewer System - UNTREATED; often goes to a lake. Removes environmental water from the outside (rain, snow). Some bad things go in grains (car oil, fumes, and dead animals). After awhile this will pollute the water supply.
- Solid waste settles to bottom and water on top forms a scum layer. The water in the middle is clear, but not clean. 3. Water flows out top into perforated pipes in the septic field
- Water slowly leaches out into the ground and down to the water table
- The sludge in the tank is treated with bacteria and other organisms that eat it to render it harmless
- Must have tank pumped out by a qualified contractor periodically
Another type of water removal system: Sump Pump Not part of the plumbing system. If a part of a building is below ground level, water will try to come into it Find the lowest point in the basement, put in a sump crock. Water will flow into it and collect in that crock. When there is enough water in the crock, the sump pump will pump the water out and onto the property.
pH scale (potential for hydrogen) is 0 to 14. 0 = acidic, 7 = neutral, 14 = basic (more alkaline, hard water) High alkaline water is quite common (caused by a high mineral content, often calcium-based).
What’s in our water? Three basic components (besides H 2 O)
- Dissolved solids - (iron, calcium, lead (bad), sulfur, magnesium, salt) Hard water (alkalinity) - deposits, soap won’t lather, dry skin & hair. Soften the water to address hard water; replace the hard water minerals (calcium, magnesium) with salts to bring the pH down (sodium-chloride). Scale formation – scale is built up minerals on surfaces. As water gets hotter, scale builds more quickly. Pipes get filled up, water flow is reduced. Scale is also an insulating material so there isn’t efficient heat transfer through pipes. Add chemicals to treat and reduce the scale. Don’t use just tap water in a boiler.
- Dissolved gases – oxygen and carbon dioxide
- Suspended solids – dirt, leaves, trigs, bacteria
High temperatures have adverse effects on water!
- An increase of scale
- Corrosive action – corroding pipes with heat
- Microbial growth increase
- Liquids expand with heat
Water Heating Systems – Domestic Hot Water (DHW)
Indirect water heaters (electric heaters)
Consists of a large tank that is filled with water. An electric element with a heater is immersed in the tank. The water is then heated to a preset temperature. This tank is also equipped with a float valve. (when the water level in the tank reaches a low-point, a valve open to let fresh (cold) water in the tank.
“Fire-tube” boiler
Heating water in larger building where water enters a very large tank and surrounds a series of tubes through which either fire or stream travel. Also can be a tank-less heater. “Water-tube” boiler
Similar to a fire-tube boiler but water passes through the tubes and the heat from fire or stream is in the tank through which the tubes pass, again heating the water.
Instantaneous heater; tank-less heater, booster heater
Instantaneous heaters don’t store hot water but create it on the spot. A booster heater is used to further increase the temperature of water that is already hot. We use these on dishwashing machines, where water must be to 180 degrees F. Tank-less heaters are fueled by electricity and natural gas or propane.
Insulation Insulate hot water pipes to keep water hot Insulate cold water pipes to prevent condensation, protect from pipes freezing, and keeping water cold in the summer time.
DHW Safety
Typical supply temperature >> 110 – 115 oF (for human contact) Plumbing fixtures (faucets and showerheads) that contain heat sensor. If the sensor finds that the water is too hot, cold water is automatically mixed in with hot water. DO NOT EVER exceed 115 degrees F at the tap (faucet).
Typical supply for dishwashing, cleaning >> 180 oF To kill all bacteria; may have a booster heater
OSHA requirements for DHW safety: the paradox Legionella is a name of a bacterium (infested hot water). Occupational Safety and Health Administration recommends that domestic hot water storage tanks be held at a minimum of 140 degrees F, with water circulating through the system at a minimum of 122 degrees F. Someone can be scalded at 120 degrees F.
Question: Can we rely on the guests/employees to protect themselves against scalding? No. Anti-scald device (you can add to a fixture or purchase a fixture with the device; device set at highest temperature that it will produce). That’s why we would implement a heat sensor to guest bathroom fixtures.
**Water Systems – Water for Equipment (not for human consumption) **Special Water Treatment Issues****
Cooling Systems
Cooling tower water, water exposed to environment (outdoors), need to control microbial growth because of legionella.
Hot Water for Heating (not for drinking/human consumption)
Dissolved solids scale formation Suspended solids bacteria/microbes
Water Entertainment -- Swimming Pools and Spas
Pools Chemistry – Chlorine or bromine are the most sanity methods for humans to swim in. High mineral content and high pH = skin and hair dries out. Low pH = high acid and will
swimmers’ eyes and skin. Pool temperatures should be between 78 and 82 degrees F. Ozone (O 3 ) is a powerful oxidizing agent (better at killing than chlorine and bromine), have to check location to see if it is appropriate to use. Spas Chemistry issues the same as for pools – Chemicals decay even faster with warmer temperatures
People that sit in hot tubs – sweat, body oil, lotion, shampoo, urine, laundry detergent (bathing suits), kids is diapers (feces), virus, bacteria, blood… If the jets stop and there is a foam, that is all these things in suspension. Procedures: 1) Shut it down 2) Drain it 3) Clean it 4) Refill it 5) Shock with chemicals 6) Rest.
Water is usually held between the range of 102 and 105 degrees F. Because many types of microbes (bacteria, yeast, viruses) will multiple at this temperature, a spa will have more chorine/bromine levels than a swimming pool.
Electrical Systems
What is electricity? The result of the negative charges of electrons and the positive charges of protons in an atom. Creates an electrostatic charge.
How it is distributed:
When it has reached MY facilities there are transformers : step down (decreasing the voltage) and step up (increasing the voltage).
First stop, transformer Cooling options: Dry (air), air-cooled (older transformers but PCB’s are carcinogens) Location: Above ground or below ground/vault (older cities have metal gates so the transformer will most likely be below-ground).
Definitions: Volt. The measure of electrical pressure. This is the force that causes electricity to flow. Volts = Amps x Ohms
Electricity flows in units called amperes or amps. Electricity encounters friction which is measured in units called ohms. A watt is a unit of power. Watts = Volts x Amps. 1,000 watts = 1 kilowatt. Companies use kilowatts to bill commercial customers for electricity. The measure of overall consumption is called kilowatt-hour.
2 kinds of electrical current: direct current and alternating current. DC current is generated by a battery. It is called DC current because it is supplied at a constant time rate at either a positive or a negative polarity (electrical charge). On a graph, it stays positive. Most utility companies provide AC current which looks like a sine wave (both positive and negative polarity).
Frequency is called Hertz. The normal supply for electrical equipment is 60Hz in America but 50 Hz in Europe.
Electricity is made in a generator. The generator uses metal coils that are attached to a shaft. The shaft spins and rubs against magnets, generating an electrical charge. Most popular plants are nuclear generated and use coal, then natural gas, then petroleum.
Circuits with higher current travel to electrical panels that then distribute the power to various rooms or sub-circuits. Fuses are only show that they have been exposed to too great a current and burn out. Circuit breakers break the circuit when exposed to too much current but can be reset. Electric wires are made of copper. The most common types of wire protection is non-metallic sheathed cable (Romex).
Buying Electricity Reading meters: o Consumption: this is the total amount of electricity used, measured in kilowatt-hours. o Demand: this is the max. rate…business (never residential), measured in kilowatts.
Reading your electric bill: o Consumption charges o Demand charges o Ratchet clauses (facility charge) – also based on demand o Other charges Managing the bill o Peak-shaving – when equipment is turned off during peak usage times to reduce the spike in electric demand (reduces the demand charge) o Load-shedding software – automated, and can monitor the actual demand at the demand meter in real time. None Essential loads: Storage lighting, pool heats, central A/C, ventilation, non-essential lighting Do not shed: refrigerators, water pumps, elevators, fire pumps, emergency lightening…
Issues with power quality: surges (too much voltage), transients (intense bursts of high voltage), sages (too little voltage), brownouts (electrical sags at 5% greater in voltage), blackouts (loss of power), electrical noise (static on the electrical line).
Electrical Safety
used to create light is wasted in heat, not efficient (low efficacy of 15-20 lumens/watt), short life (800-1,000 hours). b. Tungsten Halogen. Halogen gas and tungsten filament. CRI=100. Instant start time and low CCT. Better than regular incandescent lamps because of the life (TH has a life of 3,000 hours), and lumens (TH gets 1,200 lumens/watt). They are still hot though. Foodies might see the new tungsten halogen lights with dichroitic coating.
2) Electric Discharge Lamps a. Fluorescent lighting (CFLs). Compact Fluorescent Lamps. Various shapes and sizes (in classrooms). Uses some sort of gas to produce light. Ballast takes energy, creates an arc, shooting into tube, exciting gases/phosphurs. Pros: more efficient because of less wasted heat. Produces 40-80 lumens/watt. 4:1 ratio – incandescent lamps use 4x the energy of CFLs to produce the same amount of light. Longer life (7,000-20,000 hrs). Cons: Poor CRI (50-70 range, but has improved recently to 80-85). Mercury disposal is an issue. Poor CCT: very cool, green or blue. Hard to dim and slow strike time. It is also temperature sensitive (won’t start in cold weather). b. High intensity discharge lamps (HIDs). Issue: “strike” time, or time to get lamp fully illuminated. $20/lamp. Types of HID Lamps:
Mercury Vapor – used in parking lots, being discontinued Moderate efficiency (15 - 60 lumens/watt) Long lamp life (12,000 - 24,000 hours) Greenish color light (CRI 45-50) These are going away, due to mercury content and relatively low efficiency
Metal Halide - popular, used in BOH hospitality applications Improved efficiency (80 - 100 lumens/watt) Moderate lamp life Dies quickly at the end of lamp life (“lumen depreciation”) Light color not bad, as long as you don’t need precision in color representation (65- CRI, 3500 – 4000 CCT) Big growth area in lighting industry – you’ll see these in retail (big box) applications
High-Pressure Sodium Vapor – exteriors, warehouse lighting, less popular Very efficient (85 - 140 lumens/watt) Long lamp life (16,000 - 24,000 hours) Color: Yellowish, CCT = 1900 – 2000 Caution – some products contain mercury, creating need for special handling when disposing. Mercury-free options are available.
Low-Pressure Sodium Vapor – very efficient, great for BOH areas Most efficient (150+ lumens/watt) Reasonably long lifetimes Yellowish light (CCT = 1800 – 2000) Also see these in storage warehouses, some factories, etc.
3) Light Emitting Diodes (LEDs). Semiconductors that illuminate when electrons move around. Pros: no filament, semiconductor is a little chip, gives off no heat, all energy goes to light,
extremely efficient, very long life: red (100,000hrs), green, blue, yellow (50,000hrs), and good optical control (focus, dim). Cons: size is limited, expensive (but decreasing).
How much light in a space? There is general lighting (enough to move through the space) and task lighting. Don’t use fluorescent lights in bathrooms.
Centralized Heating Systems. We will either circulate ho water throughout the building or circulate forced air. This is done using a boiler. o Boilers generate steam or hot water. ▪ Steam is generated through radiators and traps. A particular boiler, boilers water and creates a low-pressure steam. This steam circulates the building. As steam cools of, the water vapor condenses and must return back to the boiler (this is what a trap does). CON: control of individual space temperature is a problem because the valves are unreliable. ▪ Hot Water Systems (a.k.a. hydronic) circulate hot water and glycol (antifreeze) throughout pipes in the building. o Baseboard heating. Mostly in residences and offices. o Radiant Heat. Mostly in residences. Some luxury properties put these in their bathrooms. These are pipes that circulate through the floor so there aren’t drafty areas in the room. o Fan Coils. These are most often in guestrooms and offices. Looking inside the fan coil unit, the top part is radiant (electric heat), underneath that is the fan, and the bottom part are coils for cold water. o Air Handling System. These are for large systems and work by using the buildings hot or cold water and streaming them through coils and blowing air over the coils to heat/cool the room.
Piping arrangements: This uses the principal of supply and return. 2 pipe system. One pipe supplies water to the fan coil unit and one to remove the water and return it to the boiler. The chiller system also uses the same pipes. Can’t switch from heat to chilled air (one only), but cheap to install 3 pipe system. Only a single return line so the cold water will need more chilling and the warm water might need for heating. This is not energy efficient, only benefit is not installing that extra pipe. 4 pipe system. Expensive to install but this is what you should have to assure customer comfort.
Forced-air Systems. Mostly residences but some small commercial buildings might use this. Burning some kind of fuel (fuel oil or propane), where air circulates around it and goes through ductwork (metal tubes that let air flow through the house), then it comes out through floor registers. It gets drawn back in through a return duct so the air comes back in and gets reheated.
Heat Pumps. This is a form of electrical heating. These can be centralized or decentralized. They are air- conditioning units in reverse. Instead of releasing the heat in the condenser out to the open air, the cycle is reversed and the condense heat is blown into the guest room. These are in residences too. These are good for places with mild winters.
Safety tip: A pipe outside your house is for exhaust from a furnace. Keep it clear, otherwise, carbon- monoxide could get in the house!
PRVs. Pressure relief valve. Heating systems employ this to prevent boilers from operating at too high a pressure. The valve is set to open and release steam from the boiler if the pressure reaches a certain level.
Boilers should also have carbon monoxide detectors in case of a leak. Make sure an employee has a boiler operator’s license.
Energy Conservation: Maintaining heating equipment Insulating ductwork and pipes Weather-stripping – preventing infiltration Door closers
COOLING SYSTEMS
Sealing the building Window replacement Overhead fans Setback thermostats (digital) Occupancy sensors
Building Design and Renovation: Design for solar exposure Solar heating systems Radiant heat – running heating hot water tubes through a room’s floor Revolving doors Integrated PMS/FO systems – property management system connected to guest thermostats Card-key systems – if the key is in the slot, the power is on
Air-conditioning is conditioning the air (not always cooling it). Components include humidity, filtration (cleanliness), and ventilation (air exchanges).
Definition of comfort air conditioning : “the process of treating air so as to control simultaneously its temperature, humidity, cleanliness, and distribution to meet the comfort requirements of the occupants of the conditioned space.”
Comfort zone depends on sensible heat, relative heat, the season (getting acclimated) and how people are dressed. Temperatures are set to meet the desired conditions at the “breathing line” in a space We detect temperature in our heads A thermostat will be 3-5ft. above finished floor (aff) and it will measure the temperature and humidity and adjust accordingly
Ideal “ambient condition” ranges: Humidity: 40-60% relative humidity range. If the humidity is too low it will cause static discharge. Temperature: 68-78°F All depending on air movement
Activities affect peoples’ comfort level: In restaurants, employees are hot and customers are cold.
Psychrometrics. The study of air and its qualities. A psychrometer measures the relative humidity. BTU (British thermal unit). The amount of heat that must be added to one pound of water to raise the temperature one degree Fahrenheit. Cooling ton. One cooling ton = 12,000 btus.
Cooling loads : Internal (hot water pipes, machinery like computers and lights, people, kitchen equipment). External (sun, roof, walls, windows, doors, sensible heat/humidity, infiltration).
Refrigeration Cycle. Used to remove heat from air in a space. This is possible because of Boyle’s Law: At a constant temperature, the volume of a gas is inversely proportional to the pressure upon it. When there is a big space (big volume), the pressure is low and vice versa. The refrigeration system is composed of a refrigerant (gas used to transfer heat), a compressor, condenser, expansion valve, and evaporator:
