Hobs - Did you know?

The hob is used for boiling, frying, steaming, simmering and braising. It primarily works by the conduction of heat from the flame through the pan surface. A certain amount of radiant heat is also generated. A large volume of primary air is provided so that the pan can be located as close as possible to the burner head and so gain the heat from the flame. The flame should not be allowed to lick up the side of the pan as heat will be wasted. 

The hotplate is usually a solid steel flat plate or ceramic surface, on which the pan sits, or it can take the form of a griddle, which is used for dry-frying foods such as eggs etc. The flame is located beneath the metal and heats it to the desired temperature.

The heat setting of a hob or hotplate often has a grading, such as simmer, medium and high. The flame does not adjust to the heat requirements of the food being cooked and if set too high, the contents of the pan may boil over or burn. Some appliances have thermostatically controlled burners. They work using a contact sensor that is filled with a volatile fluid that, when heated, expands forcing the gas valve to close down to a by-pass rate. With freestanding cookers all control taps and the oven thermostat are located on a pipe, named the float rail, which is located behind the control knob fascia. During any maintenance work all these gas connections should be sprayed with leak detection fluid to ensure they are gas tight. The gas burners used with the associated parts of the cooker are generally unprotected, in terms of flame failure. This means that should the flame go out, gas is allowed to discharge freely into the room. The oven will be found to have a flame failure device fitted, usually of the liquid vapor type, which will shut down the main flow of gas but will still allow a discharge through the by-pass. Cookers supplied by LPG are controlled and all control taps generally require the operation of a thermo-electric FSD before gas is allowed to flow freely. 

The Grill - did you know

The grill is used for toasting, grilling or browning previously cooked food. It works

by directing radiant heat that has been produced on the surface of a red-hot fret,

mesh or gauze surface, on to the food. There are two designs of grill.

First, those referred to as conventional grills, as they have been around the longest.

The grill consists of a pressed steel burner, fed via an injector at one end and located

beneath an expanded metal fret. The flames, on leaving the burner, heat the metal fret

and cause it to glow red-hot. The combustion products rise by convection through

holes in the canopy top. The biggest problem with this design is the problem of

uneven cooking, a result of the burner failing to heat the whole surface of the fret

uniformly.

In the second design of grill, known as a surface combustion grill, the injector feeds gas

into the primary air intake, this entails some 80–90% of that required for combustion.

The mixed gas and air now travels to the centre of a sealed chamber, which has a fine

metal mesh burner surface where the ignition probe is located and where combustion

takes place, the air/gas mixture clings to its face, producing an evenly heated radiant

surface across the entire burner.

Deep Fryers - Did you know

 Deep fryers:

These are appliances that hold a quantity of oil or fat in which food such as chips, fish and doughnuts are cooked. There are two different designs - one that has a flat bottom with the oil heated directly from below and a second type has oil that is heated at a location above the base so maintaining a cool zone below the flame in which old food particles can sink without carbonizing and spoiling the flavor of the food load. There are two methods of heating the oil using this design of fryer. In the first method there is what is known as a V-shaped fryer, with the lower V section below the burner. The second method requires the gas flame to be fired directly into tubes that pass through the mass of the oil. With the flat bottom fryer it is essential that, before each frying all old particles are strained from the oil. The heat input can vary between 8 kW and 40 kW depending on the size of fryer.

Grill and Salamanders - Did you know

Grill and Salamanders

Under-fired or flare grills give a heat source below the food, operating up to 30 kW. The grill consists of a burner firing upwards on to a bed of refractory ceramic or pumice material. The food is placed on a series of bars. As the hot fat from the food drops, it is burnt off in the form of an ‘uncontrolled’ flame, giving the meat a characteristic appearance and flavor. 

Horizontally fired grills use surface combustion plaques between 3 kW and 12 kW and are often accompanied by a rotisserie to cook food. The fat from the food can drop to be collected in a container at the base. Over-fired grills or salamanders have the heat source above the food and operate between 5 kW and 16 kW. They can also be used for toasting. This type of grill often has a grooved solid aluminum branding plate on to which the food is placed. This plate allows the hot fat to drain away but at the same time assists in cooking the food on both sides due to absorbed heat that is held in the aluminum plate.

Salamander

Grill

Dangers of CO (Carbon Monoxide) and the Effects of CO in the Air

                             Carbon Monoxide

What is Carbon Monoxide?..

Carbon monoxide, or “CO,” is an odourless, colourless gas that can kill you. CO in the environment can have a devastating effect on human health. For most of us it would be the most dangerous gas we might ever experience. It is often referred to as the ‘hidden gas’ because it is very hard to detect. However, the effects of CO are quite dramatic and in high concentrations it will kill within a few minutes.

When we breathe, our lungs absorb oxygen. However, CO is absorbed more readily into the blood stream than oxygen and when our haemoglobin, or red blood cells, become saturated with CO, no oxygen can be absorbed. One of the functions of oxygen is to remove waste matter from our tissues, so without oxygen our blood rapidly become poisoned. 

What percentage of CO can be harmful and what percentage can kill us?

CO in air  -  0.01%

Saturation of CO in blood  - 0–15%

Effects of CO in adults - Slight headache after 2–3 hours  

 

CO in air  -  0.15% - 0.3%

Saturation of CO in blood - 50–55%- 55-65%

Effects of CO in adults - Severe headache, nausea, and dizziness within 10 minutes; increased breathing and convulsions, leading to collapse, possible death after 15 minutes.

Yellow flames coming out from gas appliances is a sign that your appliance isn't burning correctly and efficiently. Thus, its important to keep your appliance in good health by servicing it regularly. 

Gas Regulators - what are they and how do they work?

 What is a gas regulator?

A gas regulator, also known as a gas pressure regulator, is a mechanical device used with a gas cylinder. It’s designed to slow down the compressed gas rushing out of a cylinder and release it in a controlled and steady stream to the appliance it’s connected to.

Which one is right for you?

There are all kinds of gas regulators available. Choosing the correct one for your installation or appliance is extremely important. First we have to understand why we need one and if it should be used indoors or outdoors.

This is your common low pressure regulator with a gauge. This is used on cooking appliances and heating appliances. This is attached to a 9 Kg bottle and will be connected to the appliance.  

This is a low pressure bullnose regulator. This one is ideal for outdoors installations and should be mounted against a wall. This regulator is for bigger sized cylinders like the 19 Kg or 48 Kg.

(Gas Dryers) Did you know?

 

Have you heard about gas dryers?

According to Energy Star, a government-backed program that helps consumers learn about energy-efficient homes and products, your tumble dryer (or clothes dryer) is most likely the most energy-hungry appliance in your home even more than your refrigerator. 

If you’re shopping for a new dryer, now is a great opportunity to learn about ways to save energy. 

Gas dryers heat up much more quickly and generate more heat which in turn dries clothes faster. An electric dryer takes longer to reach its hottest point and doesn’t get as hot, so it uses electricity for a longer duration because it takes longer to tumble the clothes dry. If you want to save money on electricity, a gas dryer is well worth the consideration.

We break-down the pro's and con's of the gas dryer.

Pros:

• More energy efficient than electric dryers. 
• Dries a load of laundry more quickly.
• Uses a standard electrical outlet.

Cons: 

• Requires a gas hook-up.
• Must be placed near a vent that goes outside the home.
• Often more expensive than a comparable electric dryer.

Importance of  a Service:

Both of these types of dryers (electric or gas) pose safety hazards that can be mitigated with proper installation, maintenance and usage. It’s worth noting that the safety concerns about gas and electric dryers apply to pretty much any major home appliance. It is recommended to have your gas appliances and installations serviced regularly to ensure that they use gas efficiently.

Designs:

                                       

LG Ultra Large Capacity
Gas Dryer
with Sensor Dry Technology

Need more convincing? Watch the video below.