Radiant heaters are simpler than warm air heaters in many ways. They have no large fans moving air around the building and, in the case of electric radiant, no combustion at all. This simplicity means they are often reliable for years with little attention. But that same simplicity can lead people to ignore them completely, and a neglected radiant heater still loses efficiency, can become unsafe and will eventually fail.

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This guide explains the maintenance that radiant heaters need. It covers both gas-fired radiant tube heaters and electric radiant heaters, because the two have quite different requirements. It is the companion to our warm air heater maintenance guide.

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Why Radiant Heater Maintenance Matters

 

Even though radiant heaters are simple, there are four good reasons to maintain them rather than ignore them until they fail.

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• Heat output: Radiant heaters work by emitting infrared energy and reflecting it down to where it is needed. Dirty emitters and dull, dusty or corroded reflectors reduce the heat that actually reaches the floor, so the heater delivers less while using the same energy

• Safety: Gas-fired radiant tube heaters involve combustion and a flue, so the same safety considerations apply as for any gas appliance. Electric radiant heaters run very hot and rely on sound electrical connections and mountings

• Reliability: Catching a developing fault during a planned inspection is far cheaper than an emergency failure in the middle of winter

• Lifespan: A radiant heater that is kept clean and checked lasts longer than one left to accumulate dirt and run with failing components

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Maintaining Gas-Fired Radiant Tube Heaters

 

Gas-fired radiant tube heaters burn gas to heat a tube, which radiates heat downward with the help of a reflector. Because they involve combustion and a flue, they need a proper annual service by a qualified engineer, much like a warm air heater. A thorough service should cover the following.

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The Burner and Combustion

 

The burner heats the radiant tube and is the part most affecting efficiency and safety. A service should include inspecting and cleaning the burner, checking ignition and flame stability and carrying out a combustion analysis to confirm the burner is operating correctly. A burner that is out of tune wastes gas and can produce unsafe combustion.

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The Radiant Tubes and Reflectors

 

The radiant tube and its reflector are what actually deliver heat to the space. A service should include inspecting the tubes for corrosion, distortion or damage and cleaning the reflectors. Reflectors that are coated in dust and dirt reflect far less heat downward, so keeping them clean directly preserves the heater's output. The tubes should also be checked for any signs of failure that could affect combustion or safety.

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The Flue and Ventilation

 

On flued radiant tube heaters, a blocked or damaged flue prevents combustion products escaping safely. A service should include checking the flue is clear and sound and that combustion air supply and ventilation are adequate for the appliance.

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The Gas Supply

 

A service should include checking the gas supply pressure and confirming there are no leaks. Correct gas supply pressure is essential for the burner to operate safely and efficiently.

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The Controls and Safety Devices

 

Radiant tube heaters rely on controls and safety devices including thermostats or radiant sensors, flame failure devices and any overheat protection. A service should include testing these to confirm they work correctly, as the safety devices are what protect the building if something goes wrong.

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Maintaining Electric Radiant Heaters

 

Electric radiant heaters are much simpler. There is no combustion, no flue and no gas supply, so there is no burner to tune and no combustion products to manage. This means maintenance is largely a matter of inspection and cleaning rather than a full combustion service, and the safety focus shifts to the electrical side.

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Maintenance of electric radiant heaters should include:

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• Cleaning the emitters and reflectors: Dust and dirt on the emitter and reflector reduce heat output. Keeping them clean is the single most important maintenance task for an electric radiant heater

• Checking the electrical connections: Electric radiant heaters run hot and draw significant current, so connections should be checked for security and signs of overheating by a qualified electrician

• Inspecting the mountings and guards: Confirm the heater is securely mounted, that any guards are in place and that nothing has been placed too close to the heater

• Checking the controls: Confirm thermostats and time controls are working and set correctly

• Inspecting the emitter elements: Look for any damage, sagging or failure of the heating elements, which reduce output and may need replacement

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Because there is no combustion, electric radiant maintenance does not require a gas-qualified engineer, but electrical work should still be carried out by a competent electrician.

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Maintenance Between Services

 

Beyond the annual inspection, there are simple checks that building staff can carry out to keep radiant heaters performing well:

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• Keep reflectors and emitters clean: In dusty environments, reflectors and emitters accumulate dirt that cuts heat output. Periodic cleaning makes a real difference

• Keep the area below and around heaters clear: Stored goods or equipment placed too close to a radiant heater are a fire risk and can block the heat. Maintain the manufacturer's clearances at all times

• Look and listen: Visible damage, sagging tubes, soot on a gas heater, or a smell of combustion are all signs worth reporting

• Check the controls are set correctly: Confirm thermostats and timers have not been overridden or knocked out of setting

• Watch the heat: If an area that used to be comfortable no longer is, the heater may be losing output and should be inspected

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Warning Signs a Radiant Heater Needs Attention

 

The following are signs that a radiant heater needs to be looked at:

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• Reduced warmth: An area that used to feel warm under the heater no longer does, suggesting reduced output from dirty reflectors, a failing element or a combustion fault

• Visible damage: Corroded, distorted or sagging tubes on a gas heater, or damaged elements on an electric heater

• Dull or dirty reflectors: Reflectors coated in dust and dirt that are no longer directing heat efficiently

• Smells or soot: On a gas-fired radiant tube heater, any smell of combustion or visible soot needs immediate attention

• Signs of overheating at connections: On an electric heater, discolouration or a burning smell at electrical connections needs immediate attention

• Frequent lockouts: A gas radiant heater that repeatedly shuts down on its safety controls is signalling a fault

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When Maintenance Is No Longer Enough

 

Maintenance keeps a sound radiant heater performing well, but it cannot rescue a heater that is corroded, worn out or obsolete. When tubes are corroded beyond repair, elements keep failing, parts are no longer available or efficiency has dropped well below modern equipment, replacement becomes the sensible decision.

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Hadar supplies a full range of radiant heating for replacement, including gas-fired radiant tube heaters such as the Space-Ray LR and the high-efficiency Space-Ray AD, and electric radiant heaters including the Sorrento Ceramic, Linea and Apollo. The right replacement depends on the building, the fuel supply and the application.

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Where to Start

 

If your radiant heaters have not been inspected in the last twelve months, the first step is an inspection before the heating season, by a qualified engineer for gas-fired radiant tube heaters or a competent electrician for electric radiant heaters. From there, a regular schedule of inspection and cleaning keeps them performing well.

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Hadar Industries supplies radiant heating equipment across the UK. If your radiant heaters are reaching the end of their life, contact us today to discuss a replacement.

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Frequently Asked Questions

 

How often should a radiant heater be serviced?

 

Radiant heaters should be inspected and maintained at least once a year, ideally before the heating season starts. Gas-fired radiant tube heaters need a full annual service by a qualified engineer because they involve combustion and a flue. Electric radiant heaters need an annual inspection and clean, with any electrical work carried out by a competent electrician.

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Do electric radiant heaters need servicing?

 

Electric radiant heaters have no combustion and far fewer serviceable parts than gas heaters, so they do not need a combustion service. They still need regular maintenance, which is mainly cleaning the emitters and reflectors, checking the electrical connections and mountings, and confirming the controls work. Keeping the emitters and reflectors clean is the most important task as it preserves heat output.

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What does a gas radiant tube heater service include?

 

A service covers the burner and combustion, the radiant tubes and reflectors, the flue and ventilation, the gas supply, and the controls and safety devices. A combustion analysis confirms the burner is running correctly, the reflectors are cleaned to preserve heat output, and the safety devices are tested to confirm they work.

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Why is my radiant heater giving out less heat?

 

The most common reason is dirty reflectors and emitters, which reflect and emit less heat when coated in dust and dirt. Other causes include a failing heating element on an electric heater, or a combustion fault or corroded tube on a gas heater. Cleaning is the first thing to check, followed by an inspection if the problem continues.

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When should I replace rather than repair a radiant heater?

 

Replacement usually makes more sense than repair when tubes are corroded beyond repair, when elements keep failing, when parts are no longer available, or when efficiency has fallen well below modern equipment. A modern radiant heater delivers better output and efficiency than a worn-out older unit.