Warehouse Heaters: A complete guide for every warehouse owner

Warehouse Heaters

Warehouse heater

Warehouse heaters are a necessary comfort for many businesses and building operators where productivity is important in getting the job done.

Due to the spacious nature of warehouses, it is natural to have temperature issues regardless of how perfect the warehouse space was designed. Even in cases where the warehouse was built with modern technology, the temperature balance will still be affected due to shipments and delivery activities (which are inevitable). In addition, it is not easy to detect holes in tall ceilings, as well as plenteous windows and doors, gaps and crevices.

As a warehouse owner or worker, you would have noticed the striking difference in air temperatures between the ceiling and ground floor.

The reason for this temperature shift is explained by science –  It is a result of the density difference between cold air and hot air. As seen in the atmosphere, especially in sea areas, cold air always pushes hot air up, establishing two "fluid" layers.

The best bet to keeping a warehouse warm at all times is by installing warehouse heaters. Heaters can come in many forms and sizes, including sources of energy.

This guide will first walk you through the standard qualities of warehouse heaters. Then walk you through the types of warehouse heaters based on their sources of energy and mode of operation.

More about Warehouse Heaters

Heaters are devices – huge or small – that provide warmth to an environment such as a warehouse, home, or office. Mostly used indoors, as a means of controlling the temperature and preventing the external weather to determine the internal temperature. The process of controlling the heat system of a building (and can include warehouses) is best known as central heating . The system in charge is termed a central heating system (CHS).

Though by and large, most warehouses are heated only in areas that really require it due to costs.  Other parts of a warehouse may only include 'spot' heating or employ different unit heaters to maximize temperature efficiency.

Heat Generation in Warehouse Heaters

Warehouse heaters produce heat internally with the aid of a burner, heat pump or furnace. Heaters can be centrally located in a warehouse or hung from the roof supports, depending on the mode of operation and source of energy. Quite often, the mode of transferring the heat produced from the heater could be by convection, radiation or conduction and will be a factor of choice, cost and overall efficiency.

The generation of heat in most warehouse heaters are dependent on the design and purpose of the manufacturer.

Apart from heaters with the already-mentioned types of fuels such as gases, liquid, and solid fossils, many modern heaters are designed to utilize electricity as their main source of energy. In a baseboard or portable heater fashion, the electrical module heats ribbons which are made up of high resistance wire. Depending on the size of the environment, electrical heaters can serve as a backup heat source or a main source. However, a warehouse is likely to have an electrical heater as a supplement or backup heat source.

The heat pump system dates back to the 1950s in America and Japan. Heat extraction process in the heat pump largely depends on sources such as exhaust air from the warehouse, environmental air. The direction of heat is from the external environment... into the building.

Heat Distribution in Warehouse Heaters

Heat produced in warehouse heaters can be distributed via air, water, or radiation. Oftentimes, many heating systems combine the three means of distribution.

Distribution by water

The whole process of transferring heat from one medium to another medium is termed hydronics.

Experts in this field use pipes to transport steam or heated water from the production chamber to the rooms. Old heating systems rely on the help of gravitational forces to push the heated water in a direction. New, advanced versions require a circulator which provides the necessary force to pump the steam. After producing the heat, it is transferred to the internal air with the aid of hydro-air, radiators or any other functional heat exchanger. More often than not, radiators are installed on the walls or grounded in the basement of the warehouse. Again, the placements of radiators are determined by the purpose of the heater.

Distribution by Air

Heat pumps that make use of the warm air systems transfer heated air via a supply network of ducts and collect air through fiberglass or metal ducts. This duct network can also be found in other systems such as the evaporator coil for electrical air conditioners. To separate air from dust and small particles, the incoming air is filtered by semi-permeable surfaces known as air cleaners.

Heat distribution by Destratification

As explained earlier, the rooftops of warehouses inevitably trap some amount of heat. Instead of leaving the heat energy untapped, it can be used to heat other parts of the room through the process of destratification. The main machine responsible for destratification is a suspended fan. Mounting suspended fans on your roof supports would help re-circulate the heated air from the machines, humans and heating systems back to every part of the warehouse.

Types of Warehouse Heaters

Warehouse heaters can either be classified based on the energy source or the mode of operation. Below are the different types of warehouse heaters available in the HVAC market:

Based on Mode of Operation

Pipe Heater
Pipe heaters: 

Pipe heaters are meant to be installed inside various pipes. Aside from maintaining the internal environment of warehouses, they are also designed to aid processes that demand low heat like the production of waxes, molasses, tar or corrosion-prone substances. Unlike Immersion heaters, pipe heaters are not in direct contact with the heated liquid.

Radiant Heater
Radiant Heaters: 

Radiant heaters are designed to emit infrared radiations from the warm or hot surface of the heater. They can come in two basic forms namely; plaque heaters and suspended tubes. Either way, the mode of operation remains the same. They are not modeled to pass heat via air media; their means of emission is through objects and humans. Radiant heaters are commonly found near the ceiling or warehouse entry or exit areas, such as loading bays.

Immersion Heater
Immersion heaters: 

Compared to other heating systems, Immersion heating system is a faster means of boiling liquids. An immersion heater comes in direct contact with the liquid, making it easier for the liquid to attain their boiling points. The same model is used in a boiling ring, which is used to boil water at home. Examples of Immersion heaters are flanged heaters, screw plug heaters, circulation heaters and over-the-side heaters.

Circulation heater
Circulation heaters: 

Circulation heaters aka in-line heaters are classified as Immersion heaters. They are designed with various watt densities depending on the type of liquid the manufacturer aims to heat. Other factors that contribute to the nature of the circulation heater are the viscosity and flow rate of the liquid. Maintenance is aided by the installment of drain valves, which allows clean and easy release of the liquids used.  

Based on Source of Energy

unit heater
Unit Heaters:

Due to the availability of fuel, many warehouses bank on the use of unit heaters. Unit heaters can run on the cheap and available fossil fuels like propane, natural gas, and electricity. Unit heaters are made up of fans. These fans blow in and out of the warehouse in an adjacent position to the coil. Unit heaters can be used in bulk or as a complement to other forms of heaters.

Heat Pump
Heat Pumps:

Heat pumps are known for extracting heat from cold air and transferring the energy into the warehouse internal environment. They are designed with a refrigerant which circulates the extracted heat throughout the warehouse. Heat pumps are a perfect option for companies searching for a clean energy alternative, as heat pumps do not use fuel. It is fashioned to trap heat from the neighboring areas. Limitations include how cold the ambient temperatures are outside for extraction but can be very effective in many locations including the Dallas, Ft. Worth area.

water oil-gas heater
Water Oil/Gas Heaters (Boilers):

The water oil/gas heating system is pretty simple. It is an Immersion heating system, which uses water as its primary liquid. The heater can either run on gas or oil as fuel. It is designed with a boiler, which heats the water directly. After reaching the boiling point, the water starts changing into its gaseous state (which is also known as steam). The steam is passed through pipes and transferred to the radiator. On absorbing the heat from the steam, the radiators emit the heat energy to humans and objects inside the warehouse.

natural energy heater
Natural Energy Heaters:

The term natural energy refers to any form of green energy that doesn’t involve the use of fossil fuels for instance, geothermal energy, wind energy and solar energy. Other types of heaters can also use natural energy, since it would be firstly converted from its initial form to electric energy to work. However, these natural energy heaters rely solely on natural energy. The challenge is that natural energy heaters are more expensive to install. In a bid to support the use of clean energy, most states give companies that use green energy tax breaks.

radiant heater
Radiant heaters:

This is by far one of the most effective heating systems, as radiant heaters do not require a medium to emit heat. The radiant heating system is built on hydronics and radiation. The heat gotten from steam or warm water is utilized and emitted round the warehouse. It is often around the exits, entries and assembly or production lines.

How to Size and Place Warehouse Heaters

The next big step after deciding the best heater for your warehouse is mapping out its size and location. Like every other warehouse accessory, it has to be properly sized and installed to perform its functions well.  

Step 1: Measure the Length, Width, height, and Area

To determine the size of the heaters, the length, width, height and area of the room cannot remain unknown. Once you’ve gotten the length and width of a room, the area is easy to determine. The area of a rectangular room is gotten by multiplying the width and the length; however, we need the cubic area which is the multiplication of the three values. For example; a warehouse room that is 20 feet long, 24 feet wide and 24 feet high would have an area of 11,520.

Step 2: Determine the total area of the areas

You can get the total areas of the warehouse by adding the areas of every space in the warehouse. For instance; if the warehouse has 20 spaces with the same areas, the total cubic area is 20 multiplied by the area of one room.

Step 3: Know the desired amount of heat energy

In order to calculate the amount of heat energy needed to raise the warehouse temperature to the desired amount, you ought to know the average temperature on a regular day. Remove the value of the average temperature from the desired value to know the required temperature difference. For instance, if the average temperature picked by your thermometric tool is 35 degrees Fahrenheit, and you need the temperature to be at least 60 degrees, the required temperature increase will be a 25 degrees difference.

Step 4: Identify the factors that might affect the heat balance

As mentioned earlier, the first challenge faced by warehouse workers is of the spacious nature. It is almost impossible to detect some leaks. The best bet is to ensure there’s a heater on standby. Check the windows, doorways, garage doors and ceilings for leaks. Amend the leaks you can detect to reduce the wastage of heat energy to an extent.

How to Determine the Best Heater for Your Warehouse

Assessing your warehouse needs is key to determining the best heater for it. When assessing your warehouse, there are five important factors to consider namely;

Cubic Area

Determine the overall cubic area or square footage of your warehouse. This would help you decide how many heaters per room. Also, you don’t have to heat every room, as some rooms are not occupied by workers. Reducing the number of rooms would help reduce cost while achieving the utmost goal, which is to make the working environment habitable for your employees.

Since a watt of power is the same as three and one half British thermal units, BTU's... the best bet is to install 10 watts of heating power per square foot of the warehouse.

The Warehouse structure

Factors such as the number of employees, spaciousness of the warehouse, amount of loading docks, and the position of your employees’ offices would go a long way in determining where and how the heaters should be installed.

Available resources

In the unit heaters section, we walked you through the reason for the popularity of unit heaters, which is the availability of its fuel sources. Identify the types of fuel sources around your vicinity. Most companies transport fuel from well-occupied areas to their region. However, you could save more money by opting for heaters that use the fuel available in your region. Make a list of the resources and prices available in your area, then, choose the most available and affordable options.

Consider your Company functions

The commercial activities going on inside your warehouse on a daily basis are key to keeping the internal environment warm. For instance, warehouses that accept deliveries and shipments should plan ahead for some heat loss during those activities. You should also highlight the areas with the highest activity and the ones with the lowest activities, so as to ensure the right amount of heaters are installed in the right locations.

Know your space limitations

The size of a warehouse directly affects its temperature. Bigger warehouses require more heaters. Also, some warehouses look big on the outside, but tighten internally due to the installment of storage areas. To make up for lack of space in the ground floor, a good percentage of heaters can be installed on the ceiling  while ceiling fans would be used to destratify the heat and circulate it all over the warehouse.

Repair & Maintenance for Warehouse Heaters and When to Call for Service

Most companies that sell and install warehouse heaters and systems have maintenance personnel. Ask the seller for the kind of maintenance required by the heater you intend to purchase, as most heaters require different maintenance processes. Also, the amount of maintenance would be determined by your company’s activities.

The best way to proceed on how to best heat and maintain warehouse heaters is to request the services of a professional. We're here for you should you have any questions, both large and small as to how you should proceed with your particular situation and budget. Give us a call or fill out our service request form today.