question: Why do washers have temperature settings such as "hot cold" or "cold cold"?
comment: It's just missing punctuation. "Hot, cold" means "hot wash, cold rinse." And so on for the other combinations.
passages: However, higher-temperature washing uses more energy, and many fabrics and elastics are damaged at higher temperatures. Temperatures exceeding have the undesirable effect of inactivating the enzymes when using biological detergent.
  
  Many machines are cold-fill, connected to cold water only, which they heat to operating temperature. Where water can be heated more cheaply or with less carbon dioxide emission than by electricity, cold-fill operation is inefficient.
   Early automatic washing machines were usually connected to a water supply via temporary slip-on connectors to sink taps. Later, permanent connections to both the hot and cold water supplies became the norm, as dedicated laundry water hookups became common. Most modern front-loading European machines now only have a cold water connection (called "cold fill") and rely completely on internal electric heaters to raise the water temperature.
  
  Many of the early automatic machines had coin-in-the-slot facilities and were installed in the basement laundry rooms of apartment houses.
  
  Section::::History.:World War II and after.
   Contemporary warm glass work is almost universally done in an electrically-heated kiln, although some gas or oil-fired kilns are still used. The reason for this is the extra control accuracy and programmability available with electric heating, as well as their lower capital cost and convenient installation.
  
  All kilns for glass work require a pyrometer, usually based on a thermocouple, as knowledge of the kiln temperature is essential for controlling the process.
   Process pump specifications that are important to consider include the process flow, process pressure, pump material, elastomer and mechanical shaft seal material, motor voltage, motor electrical class, motor IP rating and pump rating. If the cold water temperature is lower than −5 °C, then a special pump needs to be used to be able to pump the high concentrations of ethylene glycol. Other important specifications include the internal water tank size and materials and full load current.
   Features available in most modern consumer washing machines:
  
  BULLET::::- Delayed execution: a timer to delay the start of the laundry cycle
  
  BULLET::::- Predefined programs for different laundry types
  
  BULLET::::- Rotation speed settings
  
  BULLET::::- Variable temperatures, including cold wash
  
  Additionally some of the modern machines feature:
  
  BULLET::::- Child lock
  
  BULLET::::- Steam
  
  BULLET::::- Time remaining indication
   Section::::Wash cycles.:Washing.
  
  Many front loading machines have internal electrical heating elements to heat the wash water, to near boiling if desired. The rate of chemical cleaning action of the detergent and other laundry chemicals increases greatly with temperature, in accordance with the Arrhenius equation. Washing machines with internal heaters can use special detergents formulated to release different chemical ingredients at different temperatures, allowing different type of stains and soils to be cleaned from the clothes as the wash water is heated up by the electrical heater.
   Section::::Water coil.
  
  The water coil freeze stat performs a similar function to the air coil freeze stat, but is used on a different type of HVAC system. Its function is to keep the freon-to-liquid heat exchanger (commonly called "liquid coils") from freezing.
   BULLET::::- The thermostat is at the top left.
  
  BULLET::::- The heat (wattage) selector switch is at the top right.
  
  BULLET::::- The switch at the bottom is a normally open switch that serves as a "tipover switch" safety device: as long as the heater is standing upright, the switch is engaged and the circuit is closed.
  
  BULLET::::- The grip for the power cord is at the bottom right.
   BULLET::::- 1994 44-liter washing machines and dryers refreshed, new control panel design
  
  BULLET::::- 1995 Final year for the 44-liter top load washing machines, final refresh of the 44-liter washing machines and related tumble dryers, all models now have a internal model number ending with A (ie, 20005-WM200A) timer models now have hybrid timers, all models equipped with magnet drain pumps, control panel refreshed once again
  
  BULLET::::- 1998 50-liter machines introduced with a all-new design, still using Quattro. Door seal moved from outer tub to door
  
  BULLET::::- 2000 Takeover by Antonio Merloni
   Of concern is recent data suggesting that, in reality, modern domestic washing machines do not reach the temperature specified on the machine controls.
  
  Section::::Home and everyday hygiene.:Medical hygiene at home.
   In older washing machines, the permanent press setting sprays moisture during the spin cycle to maintain the moisture content of the permanent press fabrics above a certain specified limit to reduce wrinkling. Most older clothes dryers feature an automatic permanent press setting, which puts clothes through a cool-down cycle at the end of the normal heated drying cycle. Modern dryers tend to include this as a standard feature.
   Electric kilns have controllers with a variety of sophistication: the simplest is the "Infinity Control", a simple open-loop power regulator. As this only controls power, rather than temperature, such a kiln must be manually controlled throughout the cycle. As firing cycles extend over several hours, potentially days for large architectural pieces, automatic unattended control is obviously important. Automatic temperature control uses a PID controller that maintains a constant set temperature. More sophisticated controllers allow the ramp heating and cooling rates to be controlled too, an important factor in glass heating. Controllers dedicated for glass kiln use have their entire heating cycles defined before use with multiple set temperatures, hold times and ramps between them. The most sophisiticated controllers of all are dedicated to glass use and allow pre-defined cycles such as "Fuse" or "Slump" to be selected from a simple menu, without their operator needing to be aware of the precise temperatures required.
   On the early electromechanical timers, the motor ran at a constant speed throughout the wash cycle, although it was possible for the user to truncate parts of the program by manually advancing the control dial. However, by the 1950s demand for greater flexibility in the wash cycle led to the introduction of more sophisticated electrical timers to supplement the electromechanical timer. These newer timers enabled greater variation in functions such as the wash time. With this arrangement, the electric timer motor is periodically switched off to permit the clothing to soak, and is only re-energized just prior to a micro-switch being engaged or disengaged for the next stage of the process. Fully electronic timers did not become widespread until decades later.
   BULLET::::- Better temperature management.
  
  Section::::Disadvantages.
  
  BULLET::::- The system can be more expensive to run when usage is high and if the fan continues or starts to run when the door is opened.
  
  BULLET::::- A thermal cutout safety device is required to prevent overheating of the heating element.
  
  BULLET::::- Increased electrical and mechanical complexity compared to a basic upright freezer or freezer chest, making it more prone to component failure.
   Usually washing machines thermostats have fewer fixed temperature detection points than the number of wash temperatures used. For intermediate temperatures, the cam mechanism uses the stop and wait method to heat to the nearest temp below the one desired, then uses only fixed timing of the heating element to increase the water to the desired temperature.
   Washer fluid may sometimes be preheated before being delivered onto the windshield. This is especially desirable in colder climates when a thin layer of ice or frost accumulates on the windshield's surface, because it eliminates the need to manually scrape the windshield or pour warm water on the glass. Although there are a few aftermarket preheat devices available, many automobile makers offer this feature factory installed on at least some of their vehicles. For example, General Motors had begun equipping vehicles with heated washer fluid systems from the factory beginning in 2006 with the Buick Lucerne sedan. The system emits a fine mist of heated water that clears frost without damaging the windshield itself. GM also claims heated washer fluid helps in removing bug splatters and other road accumulation. The company halted the production of these mechanisms after they found that it was prone to start engine fires. A different system patented by BMW first sprays "intensive" washer fluid and then standard washer fluid on to the windscreen.
   With washing machine cam timers, it is necessary to wait a variable amount of time (for example waiting for a tank of water to heat up to a preset temperature). To achieve this, the cam motor subjects itself to control by one of its switches. The timer sequence switches the cam motor off, and the motor is started again by the signal from the thermostat when the required temperature is reached.
   Around 2015 and 2017, some manufacturers(namely Samsung and LG Electronics) offered washers and dryers that either have a top loading washer and dryer built on top of a front loading washer and dryer respectively (in Samsung washers and dryers) or offer users an optional top loading washer that can be installed under a washer or dryer (for LG washers and dryers) Both manufacturers have also introduced front loading washers allowing users to add items after a wash cycle has started, and Samsung has also introduced top loading washers with a built in sink and a detergent dispenser that claims to leave no residue on the dispenser itself. In IFA 2017, Samsung released the QDrive, a front loading washer similar to the Dyson ContraRotator but instead of 2 counterrotating drums, the QDrive has a single drum with a counterrotating impeller mounted on the back of the drum. Samsung claims this technique reduces cycle times by half and energy consumption by 20%.
   Inside the Number One Electronic Switching System (1ESS) crossbar switch and certain other high-reliability designs, the reed switches are always switched "dry" (without load) to avoid that problem, leading to much longer contact life.
   BULLET::::- k = the spring constant of one washer
   Many commercial washers are built for use by the general public, and are installed in publicly accessible laundromats or laundrettes, operated by money accepting devices or card readers. The features of a commercial laundromat washer are more limited than a consumer washer, usually offering just two or three basic wash programs and an option to choose wash cycle temperatures.
   BULLET::::- Samsung (South Korea) including Kenmore (USA)
  
  BULLET::::- Sharp (Japan)
  
  BULLET::::- TCL (China)
  
  BULLET::::- Toshiba (Japan)
  
  BULLET::::- Vestel (Turkey): Vestel, Regal, Vestfrost (Denmark)
  
  BULLET::::- Videocon (India)
  
  BULLET::::- Whirlpool(US): including the brand names Acros, Admiral, Amana, Bauknecht, Estate, Inglis, Kenmore, Laden, Maytag, Magic Chef, Kirkland, Roper & Philips, Brastemp and Consul (Brazilian market)
  
  Section::::See also.
  
  BULLET::::- Centrifugation
  
  BULLET::::- Clothes dryer
  
  BULLET::::- Combo washer dryer
  
  BULLET::::- Detergent
  
  BULLET::::- Drying cabinet
  
  BULLET::::- Energetic efficiency
  
  BULLET::::- Home appliance
  
  BULLET::::- Ironing
  
  BULLET::::- Laundry detergent
  
  BULLET::::- Laundry symbols
  
  BULLET::::- List of home appliances
  
  BULLET::::- Major appliance
  
  BULLET::::- Silver Nano
  
  BULLET::::- Standpipe
  
  BULLET::::- L'Increvable
  
  Section::::References.
   Many dryers also have attachments for drying shoes or boots, or air pouches which can be folded to dry clothes in place of a clothes dryer. The dryer can be run for under an hour to warm the futon without completely drying it, or over an hour to reduce the population of mites.
   BULLET::::- 1965 Fully automatic washing machines and compact dishwasher introduced
  
  BULLET::::- 1967 Appliance export started
  
  BULLET::::- 1978 ASEA takeover, name changed to ASEA Cylinda
  
  BULLET::::- 1984 Introduction of the "Quattro" line of machines with four shock absorbers, no springs and a direct-connecting door, Asea starts selling washing machines and tumble dryers in The Netherlands
  
  BULLET::::- 1988 Takeover by ASKO, name changed to ASKO ASEA
  
  BULLET::::- 1992 Name change to ASKO, washing machine 20003 introduced with, a world's first for a domestic machine, frequency converter (FU) brushless motor, 44-liter machines refreshed, models 11003 and 12003 now with 1400 RPM.
   Temperature sensors are required to protect the motor against overheating. For some applications by other manufacturers, the increase of the motor current is also monitored. Thermoswitches or PTC thermistors which are embedded in the motor windings mostly reliably fulfil this task. They trip when the temperature limit has been exceeded and the controls switch off the motor.
  
  Section::::Functions.:Process control functions.
  