Friday, 17 August 2018


TRENCH HEATING
Trench heating cannot be discussed without first explaining what a radiator is. Radiators as heat exchangers designed to transfer thermal energy from one medium to another for the purpose of space heating.  Merriam Webster dictionary defines a radiator as any set of various devices (as a series of pipes or tubes) for transferring heat from a fluid within to an area or object outside. The English dictionary also describes a radiator as a finned metal fixture that carries hot water or steam in order to heat a room. Simply put, a radiator is any device capable of exchanging heat or simply put, a radiator is a space heater.

Brief History of Radiators
The first person to ever use the term radiator to mean a heating device was Denison Olmsted of New Haven, Connecticut in 1834. He used it as a patent for a stove that could radiate heat through a heat exchanger. The heating radiator was invented by a Prussian-born Russian, Franz San Galli between 1855 and 1857. It is quite understandable that the inventor of this wonderful device is Russian since the coldest place on the planet is Russia. The bitter cold would have been a great incentive to warm up bones while busying himself with the radiator for two years. Radiators have since the invention, been one of the oldest and most effective ways of heating buildings apart from the traditional fireplaces. Radiators transfer heat mainly by the heat transfer method of convection and can, therefore, be called convectors. The term ‘convector’ is used to describe a set of devices in which their source of heat is not directly exposed. Wall mounted radiators and trench heaters are common devices used in heating buildings nowadays and they operate following the convection method.

The Trench Heating System
 Trench heating is a system of heating that provides an even distribution of heat along the perimeter of any room and prevents draughts, condensation, and cold spots. As implied by the name, a trench is dug in the floor and a simple convector unit is connected up to the heating system and completed with the Grille (it is in simple terms a grating or screen of metal bars or wires, placed in front of something as protection or to allow ventilation or discreet observation.), the single most important feature that a trench heater has.  The amount of heat likely to be generated from this heating method depends largely on the size of the trench. Trench heaters are long and rectangular in shape, designed for the convector unit to fit in snugly. The width and the length of the trench determine the heating element or convector unit that it contains and invariably determines the amount of cooler air that can be drawn in through the grilles to allow for exchange after convection. Subtle fan systems are installed in trench heaters to allow for a greater influx of air and consequently heat to prevent the size of the trench from being a problem.
A trench heater has to have multiple grilles in contact with the tube or casing carrying the liquid or steam pumped through the radiator to increase the surface area available for heat transfer or exchange within its environment. Trench heating is most commonly installed around the edges or perimeter of a room and the location of the heating grille can be chosen by the home or room owner depending on the layout of the room or building as a whole. Features like floor to ceiling glass windows or bay windows do not pose a problem during installation for this reason.




How Does a Trench Heating System Work?
Trench heating can be either water-based or electric. In each case, water pipes or electrical elements encased in conduits, run in trenches dug beneath the floor of the room. The trench heating system is made up of a pre-insulated steel boxed casing containing an aluminium finned copper tube-heating element. This casing is kept inside a trench or hole in the ground. While cold air easily flows into the trench through the grilles, provision has been made for hot water to pass through the element in the casing. The air going into the trench is warmed up through natural convection as it rises past the element out through the grille.
The fan assisted trench heating system is only different in that an integral fan draws air into the trench and pushes the hot air out. The water-based system is designed to run off a conventional boiler, but it is very important to check that this boiler has enough capacity. The function of the trench heating system will be impaired if airflow is obstructed by dirt or damage to the grilles. Dirt or damage renders that portion of the radiator ineffective as a heat exchanger. Therefore, it is strongly advised that during summertime, trench heaters should be protected with a special cover to prevent dust. During cold seasons, the cover can be removed so that the grilles can function properly.

Possible Locations of Trench Heating System
They can be run up a flight of stairs or around the edges or perimeter of a room. They can also be fitted upstairs because the design system is such that it can be customised as per the preference of each customer. For rooms with floor to ceiling windows or bays, trench heating systems can be laid at the foot of windows so it does not cause blockage of any part of the window. They can also be fitted across the threshold of patio doors. Trench heating systems can be used in domestic or commercial buildings, in offices, hotels, restaurants, banks and residential properties.

Advantages of Trench Heating Systems over Wall-mounted Radiators.
Trench heating systems have quite a number of advantages over the wall-mounted radiator. They are the most practical form of heating glazed façades and offer the most options. They are efficient in that they use a ‘low water’ high heat output element. This need to heat very low amount of water proves very effective when used together with ground source and air source heat pump systems. Trench heating is a system that takes away the need to have standard radiators fitted on the wall. Wall-mounted radiator, as the name implies, is a radiator that is fitted to walls. As an older type of radiator system, the traditional wall-mounted radiator can be a popular choice for heating around glazed-in façades, due to its “proven track record” in heating, the fact that most people understand what it does and how it does it. However, conventional radiators pose several problems when used to heat glazed façades; they are not often aesthetically pleasing, they can be obtrusive and can obscure façades. They also tend to use up floor space and can be very susceptible to damage.
While Trench heating systems are space saving, taking up minimal floor space, wall mounted radiators take up a big chunk of space that could have been used for something else. They are not invisible, but mostly out of sight unlike the wall mounted radiators. Trench heating is also energy efficient and this makes it very economical to run.
They are efficient and quick to heat, they add aesthetic value and some sort of sophisticated look to the layout of any room they are installed in. This is because the grilles come in different materials such as wood or aluminium and in various designs. Also, trench heating systems are not as disruptive and therefore they are less expensive to install especially when building a new home from scratch. With trench heating, any finish material such as wood, rug or carpet can be used for your floors without any specific limits. They are also not as expensive when renovating a house or fitting into an already built house. Trench heating systems also dispense heat evenly in rooms such that there are no cold spots or occurrences of draught. Trench heaters are also perfect when powerful minimal heat is required. Trench heating systems are also silent in operation and require very little maintenance.
In addition to all these, trench heating systems also have health benefits. They are usually recommended in homes where one or more of the residents suffer from asthma or other types of allergies. Wall mounted radiators would cause more air turbulence that would be created by trench heaters. The lesser the air turbulence trench heaters create, the lesser the circulation of allergens and dust particles, hence creating a clean environment not just for the residents with asthma or other allergies but for residents who do not suffer from any allergies. Also, the risk of condensation building on widows with trench heating systems is reduced, making makes them ideal for use in conservatories or buildings that have floor to ceiling windows.


Disadvantages of Trench Heating
Trench heating systems have few disadvantages as opposed to their advantages, one of which is that they tend to accumulate dust. However with roll up grilles access is simple and a vacuum is perfect for a quick spruce up. They also present trip hazards to those who wear stiletto shoes!
 As versatile as a trench radiator can be, with its ability to be installed throughout different floor voids and around curved glazed façades, there are some circumstances where the trench heating system will not be appropriate for certain applications. Some of these circumstances are when floor voids are either too shallow or are completely solid. That is when digging or create a trench would be almost impossible. Also, when construction costs for creating trench channels are prohibitive, the trench heating system will not be applicable.

Output Comparison Control
Most times your heat requirements may not be exactly the same as the heat output of your chosen radiator. It is always better to have too much heat than not enough, therefore, it is recommended that you choose a radiator size with a higher rather than lower heat output and fit thermostatic valves so that you can regulate the temperature of the room.
Output range is shown in Watts and BTUs (British Thermal Units). Wattage is based on the system’s likely operating temperature and is shown as Delta 50 (∆t 50◦C) which is the current European rating. The conversion units for calculating what heat output you need from your radiator for a specific room are below
To convert Delta 50 to Delta 60, multiply Delta 50 heat output by 1.264
To convert Delta 60 to Delta 50, divide Delta 60 heat output by 1.264
To convert BTUs to watts, divide by 3.142
To convert from Watts to BTUs, multiply by 3.142
Note that the choice of grille finish may determine final heat output.


Performance Determination
Until 2015, there had been no uniform standard for determining the performance of Trench Heating. The EN 16430 standard was validated in March 2015 and provides common standards of manufacture and performance which were applied immediately. This new standard has put an end to uncertainties in the design and output of Trench Heating when comparing the performance data of different manufacturers.
The EN 16430 test procedure comprises of three parts which are the Technical specification and requirements, Test method and rating for thermal output and Test method and rating for cooling capacity. Part of this test procedure monitors the ambient room air temperature which is measured in the centre of a test booth at a distance 2m from the façade at a height of 0.75m above finished floor level (FFL). To ensure an accurate reading, the test room is designed so the ambient air temperature is measured and not mixed up with the temperature of the air entering into the coil which may be variable due to the inevitable dilution between leaving the air and entering the air.
This test does not only cover heating and cooling performance but also pressure, noise, electrical and maintenance safety.

Control Options
Heat output may be controlled by screening the radiator or its parts, introducing changes in the air circulation intensity using forced or induced draught fans or by changing the temperature of the surrounding. A full set of controls should ideally consist of a boiler thermostat, a timer or programmer, a room thermostat and thermostatic radiator valves. Room thermostats are simple dials on the wall that allow you to control the temperature of the home. They are limited in options and are inflexible because achieving the desired temperature for everyone in the building proves difficult when there is more than one radiator.
A new technology for controlling heat output is the smart heating control. It is generally used for domestic heating. It allows control remotely from a computer, tablet or smartphone. A clear advantage of a smart heating control system is that if your plans change, you can make changes remotely. Using heat controls help to minimize the emission of carbon dioxide. It also saves money on heating bills.  Heat controls allow you to schedule your heater to go off and on when needed and the areas of the home where you want to be heated can be selected also with the desired temperature.

Recommended suppliers of Premium Brand Trench Heating including Jaga Trench Heaters



The above Trench Heating Suppliers sell commercial and domestic trench heating.


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