electric unit heater,10kw electric unit heater , 15 kw electric unit heater,5 kw electric unit heater

Electric Unit Heater Range – Outputs – 3kW to 27kW

Electric Unit Heater – The FHSH electric unit heater range of low noise,efficient fan heaters for fixed installation of larger areas are suitable for heating, drying  and ventilation of larger areas. The heat output and fan speed is set via the control panel. The adjustable wall mounting brackets allow the air  stream to be directed to suit the site conditions. All of these electric unit heaters are made of corrosion proof housing of white powder coated steel panels, and are the perfect solution for your commercial or industrial electric heating needs.

Electric Unit Heater Applications & Function

The FHSH 6kW to 15 kW Electric unit heaters are not intended for use other than indoors and are only to be wall mounted , for ceiling mounted units , please see our FHTHERM-E Range , detailed at the bottom of the page .These electric heaters are appropriate for the heating of warehouses, workshops, storage rooms, show rooms, etc.

Electric Unit Heater wall mounted,3kw

The Flexiheat FHSH Range of Electric Unit Heaters

Installation time and costs are minimized when using our electric unit heaters as they are compact and completely factory wired, the unit heater only requires only a power supply connection to the heater. These units come with a control box, which should be mounted at point that gives easy access to the operator of the electric fan heaters. Several electric unit heaters may be control via one control box if so required.The controller makes it possible to control the 3 fan speeds and the 2 heat levels of the electric unit heaters. We supply as standard the wall mounting bracket and a controller , as a total package for these electric unit heaters.

Electric unit heater with wall bracket and controller


The air is carried through the heater by a fan and heated by non-corrosive elements which are regulated by the built in thermostat with at range of +5 to +35°C. The air speed is adjustable in three steps. Switching on or off, selecting half or full output and regulating the RPM is performed through the control box , which is wall mounted for easy access. The appliance is protected from overheating via a built-in temperature limiter.

Safety – There are a couple of common sense rules that apply to all electric unit heaters , these are –

  • Ensure that the area around the intake and the exhaust grille is kept free from material which could prevent the air flow through the appliance.
  • The electric unit heater has hot surfaces during operation.The heater must not be covered either with clothes or similar material since overheating of the appliance can result in a fire hazard.

Our  electric unit heaters operate reliably when installed and operated as directed. In addition to meeting all requirements of the electrical standards , the heating element is backed with a two year warranty.

Electric Unit Heater Range – Technical Information

Electric unit heater technical data-including outputs dimensions and electrical details

Our small commercial fan heaters provide a “heat throw” of 7 metres at maximum fan speed. The intelligent fan control optimizes fan speed and heat output to quickly achieve and control a comfort temperature whilst maintaining a very low noise level. Provides comfort heating while working in garages, workshops and warehouses and a great solution for commercial heating applications

Electric Unit Heater – IP Rating & Electrical Standards 

All of the FHSH Electric unit heaters are rated to IP44. This IP rating is made of up of two components , the first digit gives the level of protection that the enclosure provides against access to hazardous parts (e.g.- moving parts, electrical conductors,etc) and the ingress of solid foreign objects – for our electric units heaters this is 4 – and means that tools, wires, screws etc larger than 1mm are protected against . The second digit of the IP rating relates to the protection of the equipment inside the enclosure against the harmful ingress of water- This again is 4 for our electric unit heaters – and means that water splashing against the enclosure from any direction shall have no harmful effect. Thus IP44 means that the electric unit heater is protected from tools and small wires greater than 1 millimeter and protected from water spray from any direction.

These wall mounted unit heaters have been design an manufactured in accordance with the specifications of the following directives and standards –

MSD 89/392/EEC – 91/368/EEC, 93/44/EEC, 93/68/EEC, article 6, and the relating standard of EN 292-1, EN 292-2

LVD 2014/35/EU and the relating standard of EN 60 335-2-30

EMC 2014/30/EU  and the relating standard of EN 55014-1, EN 55014-2, EN 61000-3-2, and EN 61000-3-3

Electrical installation – The electrical installation should be carried out by a qualified electrician in conformity with prevailing regulations. The heaters must be connected to 3 Phase x 400 Volt~ via the CEE-plug, see the schematic. For connection between the control box FHCB2 and a FHSH heater, the connection should be made with a cable type H05VV5-F 0,75mm2 or similar may be used. On the back of the appliance there are two cable glands to be used for the connection to the control box FHCB2. When several heaters are connected to each other and controlled by a common control box FHCB2, it should be stated in the group centre that “the fan haters are fed from more than one group supply”


Download Flexiheat Brochure for FHSH Heaters

Premium Electric Unit Heater – Zinc Plated – Up to 20kW Output

We also supply a upgraded or premium electric unit heater , called the FHNXG range. This range of unit heaters benefits from a zinc plated metal housing and a more capable control system. It has a digital control system that allows you to –

Delay start -Programmable On feature – This feature enables the user to postpone the starting time of the electric unit heater by up to 99 hours.

Delay stop – Programmable Off feature – This feature enables the user to extend the operation of the electric unit heater by up to 99 hours.

Post ventilation – This feature (setting time between 1-9 minutes) enables the heater to cool down before eventually switching off. This saves and utilizes the energy to it’s maximum, as the residual heat is fully utilized, and blown into the area that is being heated.

Ventilation only mode – This unit can also be used in a ventilate only mode which is useful in the summer months to move hot or stagnant air.

Digital Temperature Control – The heater can automatically control the room temperature up to a maximum of 35 Degrees C. The heater will automatically come on , if the room temperature falls under the desired temperature you select ( up to and including 35 Degrees C)  , the heater automatically switches off when that temperature is achieved.

electric unit heater control panel

Control Panel for the FHNXG Electric Unit Heater



Technical Specifications of the FHNXG Electric Unit Heaters

Model 9kW15kW20kW
Output                                                                          kW6  / 97.5  /  1510   / 20
Mains Voltage                                                                 V400400400
Max. Mains Current                                                     A132126
Fan Diameter                                                             mm315315315
Air Circulation rate                                                    m³/h170022003000
Dimensions    ( L x W x H )                                         mm340 x 390 x 510530 x 390 x 510530 x 390 x 510
Weight                                                                           kg7.5910
IP RatingIP44IP44IP44

Electric Unit Heater FHNXG Model 6kw to 20kW output with wall bracket


These electric heaters are only to be mounted on a wall, and can’t be suspended from the ceiling. They also require the following clearance to the electric wall mounted heater to function safely and properly.

wall hung electric unit heater

Electric Unit Heater is Stainless Steel IP54 Rated 9kW Output 

We also do a stainless steel cased Electric Unit Heater , which has an IP54 rating for electrical protection , and has a maximum output of 9 KW . This unit is particularity suited to heating farm buildings etc, where IP54 is a requirement or in any damp or humid areas .It is also used in dry environments such as in commercial buildings, warehouses, workshops and other places where the IP54 protection standard is required or any other applications where a fire hazard is of particular concern.The Stainless steel housing and the heating elements are made of stainless steel 316H  ( this stainless steel grade has excellent corrosion resistance when exposed to a range of corrosive environments and media. It is usually regarded as “marine grade” stainless steel but is not resistant to warm sea water) and the IP54 rating provide an increased resistance to destructive dust,and  water drops falling at any angle as well as aggressive gases which can cause accelerated corrosion to a non stainless steel cased electric unit heater. This 9 kW Industrial electric heater has an inbuilt room thermostat to control the temperature and automatic protection against overheating.The step-less variable thermostat and accurately sized fan ensures an even temperature and good heat distribution.These industrial fan heaters can be controlled to give a 1.8 kW , 5.4 kW or  9 kW heat output and a a three phase heater and has an inbuilt adjustable thermostat working in the temperature range from 0-40 ° C . It is also prepared for connecting an external thermostat if so required and can be used in a fan only operation to.

Electric Unit Heater in stainless steel IP54 rated 9 kw output model FHLB9 with wall mounting bracket

Flexiheat Model ” FHLB9KW” Stainless Steel Electric Unit Heater – 9 kW Output

Output in (kW): 1.8 kW / 5.4 kW / 9 kW

Mains voltage – (V): 3 Phase x 400 volts

Max mains current -(A): 16 Amps

Air circulation – (m²/t): 700 / 1000

Fan diameter – (mm): 300

Dimensions L X B X H – (mm): 670 x 450 x 600

Weight -(Kg’s): 18

IP Rating – IP54

Larger Electric Unit Heaters – Up to 27 kW of Heat Output 


Last but not least within our range of Electric Unit Heaters are our “FHTHERM-E” units.This range of electric unit heaters have a couple of features that our other units do not have , these being –

  • The ability to be ceiling mounted, blowing the warm air down, as well as horizontally mounted, blowing the warm air horizontally
  • The ability to have a slot warm air diffuser or a discharge cone or nozzle
  • This range goes up to 27 kW of heat output, which is the largest at present that we have
Electric Unit Heater

Flexiheat FHTHERM-E Electric Unit Heater

These two options that are available for ceiling mounted electric unit heaters are shown below – to the right of the standard single row distribution grid, which the units come as default.

Electric Unit Heaters complete with Diffuser for vertical or ceiling mounting

NB – The maximum height at which you can mount these warm air electric unit heaters when using the slot diffuser is 4 metres .The discharge cone can also be fitted to the wall mounted industrial fan heater, to give it a larger air throw, if so required.


These are available in two sizes, both of which require a 3 Phase / 400 Volt supply –

The FHTERM -E 18 – Which is an 18kW maximum heat output, having three output settings of either – 6kW , 12kW or 18kW

The FHTERM -E 27 – Which is a 27kW maximum heat output, having three output settings of either – 9kW , 18kW or 27kW

The full technical details of  this range of electric unit heaters are listed below –

electric unit heater 3kW to 27kW technical information


We also supply a full range of additional accessories, which allow you to mix a proportion of fresh air and recirculated air through the heaters, either via an external wall or a roof intake.

These include – Roof Intakes, Roof Bases, Wall Intakes, Intake Boxes, Suspension Brackets to suit and Air Filters , we go into more depth in the technical manual regarding these additional items . Below are some of the accessories available for the FHTHERM wall or ceiling mounted industrial electric unit heaters –

Industrial electric fan heaters accessories, industrial fan heaters

For the full specification and additional information on the FHTERM Electric Heaters, please see it’s dedicate web page

Electric Unit Heaters for Sale

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