Commercial Heaters UK -A Guide to

Commercial Heaters – Your Options

Commercial heaters are frequently used in almost all the industries today right from manufacturing , car show rooms , retail units to warehouses . There is a variety of heaters that serve different purposes. As an unavoidable necessity, it is essential for businesses to install a commercial heating solution in their premises, to either keep they’re staff or customers , or even both satisfied. Commercial heaters can also be used to keep products above certain temperatures to ensure no damage to them , such as frost protection etc.

Installing them may be an easy task as you simply order the supplier or warm air heating installer to do so, yet the most challenging part lies in different types of questions and queries before installing-

Please go through the following points if you want to get the most out of your commercial heating equipment –


First of all, make an in-depth assessment of what your heating needs exactly are. Looking at the devices randomly may take you on the wrong route.


The following are the most common types of commercial heaters on the market based on fuel types


Commercial Gas Heaters and Propane(LPG) Heaters


Commercial Gas heaters burn a variety of either natural gas, propane (LPG),  natural gas (NG) or other gaseous fuels to generate heat. Early gas heaters were similar to the Bunsen burner in that both they used a flame to heat air locally. This heated air was spread by convection to warm an entire area. Later, the burner’s flame was used to heat a structure made of asbestos, a strong and incombustible fibre. Although asbestos structures have been replaced by fire clay and other refractory materials, modern gas heaters still operate according to this principle but the refractory materials have now been replaced by a combustion chamber and a heat exchanger, which means that any products of combustion are now expelled via a flue pipe system, being infinitely safer than the early days. They are often Co-Axial flued , or sometimes referred to as room sealed , whereby they take the air required for combustion form outside the building , via a twin piped flue system, this results in higher efficiency as the building is more air tight . Both natural gas commercial gas heaters and propane commercial heaters often use similar designs, the only difference is the gas burner.


commercial heaters

Commercial Suspended Gas Heaters – In a Garden Centre


According to their radius of effect, gas heating systems can be divided into two types: the so-called gas convector and gas-turbine heating.


With gas convector is heaters, which are used primarily for heating individual rooms. The heat generated by the combustion of the gas is then discharged directly to the environment. The gas-turbine heating, on the other hand, is generally used as a central heating system to supply entire buildings

Commercial Heaters

Commercial Gas Floor Standing Heaters – With Free Blowing Heads or Can be Ducted


Commercial Heaters – Gas or Propane – Applications

There are a broad range of different applications for gas and propane heaters. Below are just some examples;-

  • Industrial Applications
  • Warehouses
  • Workshops
  • Garages
  • Greenhouses
  • Offices and Shops 
  • Retail Outlets



There are a whole host of optional features for gas heaters. Some are indirect-fired, some are corrosion resistant, some are finned and some are even explosion-proof others are designed to provide dynamic power regulation . They can feature custom designs or have a secondary heat exchanger ( condensing warm air heating) for maximum heat transfer. Gas heaters can also be fitted with an external temperature sensors and multiple / independent timing controls to suit the site conditions


Commercial Heaters – Oil – Gas Oil or Kerosene 


Oil commercial heaters predominantly burn fuel like heating oils such as gas oil or kerosene to generate heat but waste or used oils are also a popular fuel source.


There are many different varieties of oil and kerosene commercial heaters.

Probably the most common are stationary cabinet’s types. These are usually floor mounted and either blow out warm air through their vents or through duct.

commercial heaters

Commercial Heaters – Oil Fired , with free blowing heads or ducted option

Another popular type is the suspended unit heater. These can either be wall mounted or suspended from the ceiling. These are advantageous options as they take up less space.

commercial heaters

Commercial Oil Heaters – Used in a Greenhouse Heating application


Oil and kerosene commercial heaters transfer heat to a room over a longer period of time and at a slower rate. When the oil burner is engaged, heating oil travels from the tank or reservoir to the burner by way of a pump where it becomes a fine mist mixed with air. The fuel/air mixture is then injected into the burner where it is ignited in the combustion chamber of the heater, which then transfers the heat via a heat exchanger to the space being heated.



Oil and kerosene heaters use single-phase or three-phase power.



There are a wide variety of applications for oil heaters. Examples include;


  • Warehouse & Factory heating
  • Drying,
  • Melting,
  • Annealing or heat treating,
  • Curing or tempering
  • Operations with gases and vapours,
  • Clean water heating
  • Heat process and high-purity waters,
  • Lightweight oils & degreasing solutions,
  • Heavy & medium weight oils,
  • Mild & severe corrosive solutions,
  • Caustic solutions and liquid paraffin.



Commercial Heaters – Electric Heaters


Electric heating systems are  heaters which produce heat via heating wires or heating coils. They can be roughly differentiated according to whether they store the heat, store it in part or deliver it directly or whether the heat is generated by infrared radiation or by the heating of air.



There are many variants of electric heaters. Below are the main types

1 – Natural convection

The portable heater with natural convection resembles a standard heater. It settles on the ground and heats up slowly.


  • Fresh air rises inside the cabinet by convection.
  • The air is then heated by an element.
  • The hot air exits through the openings and rises into the room.
  • There is no fan on this type of appliance.


  • The natural convection heater keeps the temperature constant, provided the room is closed or not too large.
  • Silent.

Meets the needs

  • Ideal for use for several hours at a time, for example, at the chalet or at night, in a room when the central heating of the building is switched off.


2 – Forced Convection or Blow Heaters


The forced convection heater, also referred to as forced air or blow heaters are a very popular model. These heaters are often small and light and distribute the heat with a fan.


Commercial Heaters

Commercial Electric Heaters



  • A fan moves the air around the heating elements and pushes it forward.
  • In ceramic models, electricity passes through ceramic plates that store heat in their mass, and then a fan spreads it.



  • Small and light.
  • Rather stable temperature in a closed room.
  • Heat sensation faster than with fanless model.
  • Allows directing of heat.

Meets the needs

  • Ideal for rapid heating distributed throughout a room, even when the area to be heated is large, then we do commercial electric heaters with an heat output of 80 kW , which we think are the largest portable electric heater on the UK market to date
Commercial Heaters

Commercial Electric Heaters – This is our 80kW portable electric heater



3 – Commercial Heaters -Radiation (radiant heating)


The radiant heater, also called radiant heating, often looks like a standing fan or cabinet heater. It heats according to the same principle as the lamps used on terraces. It can therefore heat a person very quickly!

Commercial Heaters

Commercial Portable Electric Infrared Heater



  • Uses a very hot element, usually halogen or quartz.
  • The element produces an infrared wave that quickly gives a sensation of warmth in a precise direction.


  • Quiet.
  • Sensation of immediate heat, much like the rays of the sun on a winter day; Warms bodies and objects, but not directly air.
  • Allows directing of heat.


Meets the needs

  • Ideal for directly heating a person in a room with a high ceiling (because hot air is rising) or in a room where there are drafts. Because of the risk of burns, it is not ideal when there are young children or elderly nearby.



Some of the key features of electric heaters are portability, precision temperature monitoring & control and design flexibility



Electric commercial heaters are commonly used throughout industrial and consumer products to heat all types of liquids, gases, vapours, and solids. In consumer products, electric heaters are commonly used for heating water, air and even flooring. Industrial warm air heating applications can utilize much higher wattages and these industrial electrical heaters can be used for applications such as heat treating for pest control , for drying of products etc, as well as standard space heating


Advantages of Commercial Electric Heating

  • Low cost in purchase
  • Low installation costs, since no piping necessary
  • No space required for burner or fuel storage
  • No chimney
  • Maintenance costs are eliminated
  • Good solution for temporarily heated rooms or buildings
  • No or little dust swirling, good for allergy sufferers


How to calculate how much heat you require , to get your correct commercial heaters or heater

Once you have determined the type of heater for you building you then need to work out which size you require. This can be achieved in the form of a simple heat loss calculation. The most important factors to consider are the dimensions of the building, the length, width and average height. There are a number of online calculators that you can use to work out the heat requirements.  The answer will typically be given in kW (kilowatts) of BTU (British Thermal Units)

Once the appropriate type of commercial heater has been decided and then installed it is advisable to appoint experienced operators at your factory premises so that they can ensure the heater(s) function correctly

Space plays a vital role as far as the correct installation of these apparatuses is concerned. Take measurement of the space where the device or devices are to be installed.

Let us help you choose the right commercial heater that’s best for your business

No single heating system is the right option for each and every commercial property. The size and location of your business, as well as the size of your budget, will all factor in to your decision. At Flexiheat UK we are ready to provide you with expert advice to help you select the commercial HVAC system that fits your business needs. Call us now or contact us via email



Gas Heaters UK – What’s your options ?

Gas Heaters UK

Gas Heaters UK – Natural gas is a fossil fuel that releases almost no classical pollutants during combustion. It has the lowest carbon content and the highest hydrogen content of all fossil fuels.

In terms of the same energy content, about 25 percent less carbon dioxide (CO2) is produced when burning natural gas than when burning fuel oil. In terms of fine dust, too, natural gas, compared to wood and oil, has a considerable advantage due to the absence of carbon black. One cubic meter of natural gas contains around 10kWh of energy

Natural gas is very affordable, so running a gas heater can be budget friendly. This type of gas is also very clean, so it is good for the environment, which is an additional benefit of using a gas heater.

Most gas heaters are designed to turn off if they fall over or overheat. This safety feature makes gas heaters even safer for your home or office.

These types of heaters provide a very warm heat and are excellent for supplementing an existing heating system. Natural gas is a popular heating option for commercial and industrial locations because it provides a very comfortable heat, making the area feel warm and cozy all winter. Gas heaters are also extremely effective and can be used in a variety of places.


There are a whole host of variants when it comes to heating with gas in the UK. Below are the main ones;-





Gas Heaters UK

A suspended warm air unit heater discharges warmth directly into the space to be heated in a conventional cross-flow manner.  Offering space saving ‘off-floor’ mounting, they are a popular choice for heating commercial and industrial buildings.



Gas Heaters UK

Gas heaters cabinets are a popular heating solution to industry. Often floor mounted and can be use in warehouses, factory workshops and commercial units. Some models use butane, propane or liquefied petroleum gas, but natural gas is the most common fuel for this type of heater.



Gas Heaters UK

A condensing unit heater is fast becoming a main stay as a heating source in industrial and commercial sector as customers look to lower their energy bills and carbon footprint; these highly efficient, energy saving units are a popular heating solution and can be found in many applications. Below are just a few examples;-

  • Automotive workshops
  • Factories
  • Retail outlets
  • Sports facilities and halls
  • Warehouses
  • Workshops



Gas Heaters UK

Propane / LPG Direct Fired Heater


Perfect for heating Garages or workshops & construction sites, a propane space heater is direct fired which means it does not have a flue. Because of this, it is especially important that safety precautions are adhered to as propane  gas or LPG can be very combustible. These heaters need to be used in an area that is well ventilated and should only be used under direct supervision.



Gas Heaters UK

Indirect Gas Mobile Heaters – Propane or Natural Gas


Indirect gas fired  mobile  heaters are very high in terms of efficiency. They provide large volume of 100% clean, dry and fume free warm air. They are most suitable in places with limited ventilation like marquees, shops, event tents, food preparation areas or exhibition halls. They can be used with a variety of flexible hoses that make the warm air  spread effectively.



Gas Heaters UK

Gas Unit Heater – Natural Gas or LPG


Gas unit heaters are designed for use in space heating applications. Gas unit heaters are typically used in areas with high ceilings, and are exposed in the space to be heated. Gas unit heaters offer low installed cost, and are able to heat large volume areas without requiring extensive duct systems. They can be installed either vertically or horizontally and can also be supplied with a centrifugal fan.

So what ever your requirement for a heater, fired by gas , either natural or Propane / LPG , then we at Flexiheat UK , have the best range of  Gas Heaters UK  wide.

Should you require anymore assistance or information on our Gas Heaters , please don’t hesitate to contact our sales team on 01202 822221 or click here for our email contact form












Industrial Space Heater UK – Your Options

Industrial Space Heater

Industrial Space Heater – Is the heating bill for your plant or warehouse too high? What about cold dock door areas and unbalanced temperatures? Is negative building air pressure a problem? Have you experienced employee complaints and lost productivity from heating or indoor air quality problems? Do you have high maintenance costs for existing heating equipment?

There are only a few common problems that result from choosing the wrong heating system, using obsolete heating/ventilating equipment or simply miscalculating space heaters

Annual space heating costs are a significant part of operating budgets for industrial units, manufacturing plants and large warehouses. Selection and application of the proper space heaters can reduce annual energy costs more than 60% and increase company profits.

What factors determine the best space heating system? Everyone wants a heating and ventilating system that meets their unique requirements at the lowest total cost,wheter it be warm air heating to deliver warm air heating power for various applications such as exhibition halls , or frost protection / temperature protection for building sites, we have a large range of many high performance industrial heaters that can achieve your required results.

Prior to selecting industrial heaters you must first decide the heating/ventilating requirements and understand all the cost factors that determine the true lowest total-cost solution for a specific facility or regular site use.


Industrial Space Heater and Space Heating Systems

A gas-fired heating system usually offers the most cost-effective way to heat industrial buildings. Oil-fired and electric heaters are sometimes used for specific space heating applications or when gas is unavailable.

Gas-fired space heating systems are classed as being either direct fired (normally warm air heating ) or indirect fired, and with adjustable thermostatic control and variable heat output, with low heat settings the can provide heat for many applications.

Indirect-fired heating systems use a method of heat transfer, such as a heat exchanger, which lowers overall energy efficiency. A flue is needed to vent the products of combustion outside the building. The inside air is re-circulated with little or no provision for ventilation with outside air. There are two popular types of indirect-fired heating systems.

1.Boiler systems (hot water and steam) have historically been a major source of industrial heat and power. These centralized systems were often used for space heating when energy costs were low, or when steam was a by-product of boilers used for nearby process heating applications.However, industrial boiler heating systems are becoming a thing of the past due to rising energy prices, poor efficiency, uneven heat distribution and high maintenance costs. Many large facilities are now replacing space heating with boilers with efficient gas or oil fired space heaters and use the energy savings to pay for the new equipment.Although condensing boiler technology has improved greatly over the last decade, and “wet systems” are still very popular.


gas condensing boiler

Gas Condensing Boiler , fully modulating with efficiencies of up to 109%

For more information on our range of condensing gas boilers or condensing oil boilers , please click on the links  for further information on our ranges. These “wet heating systems” often use a unit heaters or sometimes referred to as a hot water unit heater or steam unit heater ( if utilizing steam as the heating medium ). These are pictured below , and are basically an industrial radiator with a axial fan behind them that blows out the warm air.

These industrial unit heaters are available with a heating power of up to 400kW, dependant on the medium and temperature feeding these industrial heaters

Industrial Space Heater

Hot Water or Steam Unit Heaters




2.Unit heaters are a proven method of heating small, open spaces. Multiple heaters are installed around the perimeter of a building to match heat losses. The benefits of unit heaters include redundancy in case one unit fails, intermittent fan operation that reduces electrical costs and installation on the ceiling or mounted on walls to not take up floor space. Due to a limited air throw, their efficiency can decrease with increased height above the floor.


Industrial Space Heater

Standard Gas Unit Heaters – Efficiencies of 91%

For more information on our range of standard gas unit heaters, click here for our standard range or here for our premium range , which has a stainless steel heat exchanger and combustion chamber

The initial installed cost is relatively low for small facilities that only require a few  industrial space heaters but the costs can be higher for large buildings that require multiple heaters. A proportion of heat and energy will escape up the flue. Typical overall efficiencies can vary from 85% to 91%, and these industrial space heaters can be used in a room sealed configuration , meaning that the combustion air that is required is taken from the external air to the building.  This industrial space heater technology has moved on greatly over the last 5 years or so , with the development of  warm air condensing technology , which has resulted in this industrial space heater range achieving efficiencies from 96.6% to 108% , with a pre-mix gas burner with low NOx emissions (class 5) form more information on this range click here.Both the standard or condensing range of  these industrial space heaters ( commonly known as unit heaters ) can be fired by either natural gas or propane gas. There is also an option to have a oil fired suspended industrial heater , please click here for information on this range , which goes from 52kW to 209kW.



Unit heaters are often used in partnership with make up air heaters in industrial plants or warehouses with constant or variable exhaust loads to provide ventilation.

Industrial Space Heater – Floor Standing Option

If floor space is available, quite a few people opt to have a floor standing industrial heater, as these are often more easily installed , as they are at low level , negating the need for lifting equipment and other associated problems when installing an industrial space heater , pipework etc at high level. They are also easier to service and maintain  at low level , something which needs to be considered when selecting your appropriate industrial space heater. These can be fulled by either gas ( both natural gas or LPG , and even waste oil , bio oil or vegetable oil with one of our multi oil burners ).Here is an example of one looks like , with standard distribution heads –


Industrial Space Heater


For more information on these Industrial space heater ranges , please see our products page here

Industrial Space Heater – Selection factors 

  • How important are balanced temperatures throughout the building, from wall-to-wall and floor-to-ceiling?
  • Where will the heating system be located? Will it consume floor, ceiling, or racking space that could be used for manufacturing or storage?
  • What are the facility’s indoor ventilation requirements and air quality? How much fresh air is required by industry guidelines to dilute contaminants generated by LP forklift trucks, welding fumes, and other manufacturing processes?
  • Is spot heating or zone heating required?
  • How will the loading bay areas be heated and how fast must temperatures recover? or can I use a heated or ambient air curtain ? see here for more info –
  • What are acceptable noise levels?
  • Is makeup air needed to compensate for exhausted air? Or shall I use room sealed heaters ?

Should you require anymore assistance or information on our Industrial Space Heater range, please don’t hesitate to contact our sales team on 01202 822221 or click here for our email contact form

Warehouse Heaters UK – What are you options ?

Warehouse Heaters

Warehouse Heaters – It’s essential that when you’re working in a warehouse, it is heated in a sufficient way in order for your business to run correctly and smoothly. Without the correct heating, your warehouse wouldn’t be a suitable place for your employees to be working in, or for your customers to browse in an adequate temperature. A warm air heating system tends to be the most popular heating system for warehouse heating, as heated air is the perfect solution or ideal solution for large volumes that you get with warehouse space.

It’s important to use heaters with high energy efficiency that provide good heat distribution, and a consistent temperature – All of our industrial heaters are ErP 2021 compliant – which ensures the warmed air is produced with high energy efficiency. These units are a great heating solution, and provide consistent temperatures, with lower running costs.

The Warehouse Itself

Deciding on the right heating system will depend on several factors, such as the layout of the warehouse. Having big doors constantly opening and closing makes it difficult to control the temperature and, consequently, makes it more difficult to keep it at adequate levels. If your warehouse is very big, your heating needs will vary, compared to a smaller warehouse. You might just need heating in specific areas, so it’s important to make sure you’re getting the right heating solution for your warehouse.

Warehouse heaters – their applications  

It’s important to ensure that your warehouse is well heated throughout the winter to make sure your employees have a suitable working area.  As the colder days and nights begin to come in, your warehouse will probably require to be warmed up. Some warehouses will need the whole place warming up, whereas others will just require a particular area warming up.

There’s a number of different ways you can heat your warehouse.

Types of warehouse heaters

The next step in heating your warehouse is choosing a heating system. You need to find the solution that works best for you, so it’s important to note the differences between types of heating, so that you know what you have to work with. Please note direct fired units as not recommended, as they introduce products of combustion, which are poisonous will harm humans. Also many insurance companies will not ensure a warehouse that has direct fired heaters, because of this and also the fire hazard . Indirect fired heating options include:

Floor standing cabinet heaters

If you prefer, or if your space isn’t at a premium, you might want to check out floor standing indirect fired heaters, which are available in a number of possible installations: vertically, horizontally or even on the exterior of your warehouse – this is because these heaters have several heat outputs and burners, so their versatility makes them incredibly useful in the workplace. Floor standing heaters can be equipped with either Oil, Gas or in some case Multi / Waste Oil burners depending on the type of fuel source is preferred. Floor standing warehouse heaters are the easiest of all to maintain, as access is granted at any time, without the need of scissor lifts or any scaffolding etc, that you may need when having suspended heaters to service. Flexiheat have a wide range of floor standing cabinet heaters to suit any warm air heating application. Also ongoing maintenance is easier, as the heaters mounted on the floor space, thus it’s easy to get to the heat exchanger and burner for example.


warehouse heaters

Warehouse Heaters – Gas, Oil or Multi Oil Fired


For more information on the ranges available to you , please see our products page here

Suspended Unit Heaters

Perfect if you don’t have a lot of space, as they are out of the way of daily traffic. With plenty to choose from in terms of design, suspended warm air unit heaters are also easy to install and maintain. Suspended heaters come in all different shapes and sizes and can run off either Gas, Oil or with a wet system, whereby a boiler sends heated water to hydronic (or water fed ) unit heaters , which are basically industrial radiators with a fan behind them , that blows out the warm air. These unit heaters can also be supplied to work on low pressure steam as well as hot water, should you have steam as a resource available as a heating medium. They free up valuable floor space and can be wall mounted or mounted in high roofs, blowing the warmed air to the floor level.

warehouse heaters

Warehouse Heaters – Gas – Suspended

For more information on the ranges available to you , please see our products page here


suspended oil heaters; oil fired warm air heaters; erp compliant 2021 lot21; oil fired unit heater;

Warehouse oil heaters – Suspended

For more information on the oil suspended heaters available to you , please see our product page Oil Unit Heaters


Warehouse Heaters

Warehouse Heaters – Hydronic or Water Fed Unit Heaters

For more information on the hydronic unit heaters available to you , please see our product pages – Click here for our EPP plastic low temperature water fed fan coil heaters or or our steel cased that will do LTHW, MTHH or HTHW  water fed applications – then please click here – Unit Heaters or should you require steam powered units click here – steam unit heaters 


Spot heating in a warehouse

There are occasions when only a single spot within a warehouse or factory needs to be heated. For example:  an admin desk, a person on a production line or a lunch break area. Probably the most common type of spot heating is from an electric infrared radiation / radiant heater, which are portable or mobile , and can used in various locations as and when the heat is required. These radiant heaters use an electric element or a number of these to produce radiant heat directly. Infrared heating or radiant heating is very much suited to heating specific objects or people that are stationary, and take up little floor space. Below is a picture of infrared heaters in use.For more information on this range please see our dedicated webpage portable infrared heaters

warehouse heaters

Spot Heating with Electric Infrared Heaters



Should you require anymore assistance or information on our warehouse heaters , please don’t hesitate to contact our sales team on 01202 822221 or click here for our email contact form