Why is your towel dryer making noise? (Clicking, whistling, gurgling).
Lucas Morel
It was silent, and then one day your electric towel dryer started making strange noises. Sharp clicks when heating up, a discreet whistle during continuous operation, or worrying gurgles on a fluid-filled model. These noises, often a source of concern, are in the vast majority of cases perfectly normal and harmless — or, on the contrary, warning signs not to be ignored depending on their nature.
This acoustic diagnostic guide allows you to precisely identify the origin of each type of noise produced by your towel dryer, to determine if it requires intervention and, if so, what kind. Clicks, cracks, whistles, gurgles, hums: each noise has its explanation and its solution.
🎯 The essentials in 30 seconds
No time to read everything? Here's what you need to remember:
- Clicks on startup: normal thermal expansion — no intervention needed
- Gurgles and gargles: presence of air in the circuit (fluid models) — can be bled
- Continuous whistling: faulty heating element or thermostat — to be monitored
- Dull hum: loose fasteners — tightening the screws is enough
- Cracking on shutdown: normal thermal contraction — no worries
📋 Table of Contents
- Different types of towel dryers and their specific noises
- Clicks and cracks: thermal expansion
- Gurgles and gargles: air in the circuit problem
- Whistling: electrical causes to diagnose
- Hums and vibrations: fasteners at fault
- Rumbling and loud noises: warning signs
- How to bleed a fluid-filled towel dryer
- Diagnostic table: noise → cause → solution
- When to call a professional?
Different types of towel dryers and their specific noises
Before diagnosing a noise, it is important to identify the type of electric towel dryer you own, as each technology has its own characteristic noise causes.
Dry electric towel dryer
This is the most common type in recent installations. Heat is produced by an electrical resistance housed in the bars, without an intermediate liquid. Possible noises are limited to thermal expansion of the metal (clicks, cracks) and fastener vibrations (hums). The absence of a liquid circuit eliminates gurgles and gargles.
Fluid-filled electric towel dryer
In this type of appliance, an electrical resistance heats a liquid (usually mineral oil or a glycol fluid) which circulates in the bars by natural convection. This technology produces the widest range of possible noises: metal expansion, but also gurgles related to fluid circulation and phase change noises if the appliance contains a fluid with a low boiling point.
Hydraulic (hot water) towel dryer
Connected to the house's central heating system, this type of appliance can produce water circulation noises, hydraulic hammering (water hammer), and whistling related to network pressure. These noises are often intermittent and related to the general operation of the heating system.
💡 Identify your type: To find out if your towel dryer is dry resistance or fluid-filled, tilt the appliance slightly (after switching off and completely cooling down). If you hear a slight gurgle when tilting it, it contains fluid. If it's silent, it's a dry resistance.
Clicks and cracks: thermal expansion
This is by far the most frequently reported noise by towel dryer users — and most often the most harmless.
The mechanism of thermal expansion
All materials expand when heated and contract when cooled. For the metal of a towel dryer, this dimensional variation is in the order of a few tenths of a millimeter over the total length of the bars — imperceptible to the eye, but sufficient to create mechanical stresses at contact points between parts of the same metal or different metals.
When these stresses exceed the static friction coefficient between two parts, they are suddenly released in the form of a characteristic click or crack. This is exactly the same phenomenon that produces "creaking" noises in wooden floors during temperature changes.
When do these noises occur?
Clicks related to thermal expansion occur:
- On startup: during the first 5 to 15 minutes, when the bars quickly heat up
- On shutdown: during cooling, sometimes more pronounced than on startup because contraction is faster than expansion
- During a sudden mode change: switching from "eco" to "comfort" on a programmable towel dryer
How to differentiate them from problematic noises?
Thermal expansion clicks have specific characteristics:
- They appear only during heating or cooling phases, never during stable operation
- They are irregular (a few spaced clicks, not a continuous noise)
- Their intensity is proportional to the speed of temperature variation (more pronounced if the appliance starts after a long winter shutdown)
- They do not evolve over time — an appliance that has been clicking in the same way for 5 years does not have a problem
🌿 Rest assured: If your towel dryer only produces clicks during heating and cooling phases, and these noises have not changed in nature since installation, no intervention is necessary. This is normal and inevitable physical behavior for any metal appliance subjected to thermal cycles.
Gurgles and gargles: the air in the circuit problem
Gurgles and gargles are exclusive to fluid-filled or hydraulic towel dryers. They are caused by the presence of air bubbles in the fluid circulation circuit.
Why does air get into the circuit?
In a fluid-filled towel dryer, the heating liquid is supposed to completely fill the circuit. Air can enter in several ways:
- During installation: if the appliance was not placed in the correct vertical position during commissioning, air pockets may remain trapped in the bars
- After a long period of inactivity: especially when restarting after summer, when the fluid has partially contracted and allowed air to enter
- Micro-leak: a very slight leak at a connection point may have allowed air to enter by capillarity during a cooling period
The sound mechanism
When the heat transfer fluid heats up, it starts to circulate by natural convection in the bars. Trapped air bubbles are carried by this movement and produce the characteristic gurgling sounds as they rise in the vertical bars or pass through bends. On a hydraulic towel dryer, the same phenomenon is amplified by the pressure of the hot water network.
Are these noises dangerous?
Air gurgles are not dangerous in the short term, but they indicate suboptimal fluid circulation which reduces the thermal efficiency of the appliance. In extreme cases (a lot of air), some bars may not heat up at all if an air pocket completely blocks them. The solution is to bleed the air (see dedicated section).
✨ Diagnostic test: To confirm that it is indeed air in the circuit, touch each bar of your towel dryer when it has been operating for 30 minutes. If some bars are cold or significantly less hot than others, an air pocket is blocking the fluid in these bars — bleeding is necessary.
Whistling: electrical causes to diagnose
A whistle is a more unusual noise that deserves special attention, as its causes are more varied and some of them require intervention.
The whistle of the electric heating element
An electric heating element can produce a slight whistle or hum related to the vibration of its components at the grid frequency (50 Hz in Europe). This noise is generally very faint and constant throughout the operation of the appliance. It may slightly amplify with the aging of the heating element.
A slight and constant whistle that has been present since the appliance's installation is generally harmless. A whistle that suddenly appears on an appliance that was previously silent, or that gradually intensifies, deserves investigation.
The whistle of the thermostat
Some mechanical thermostats produce a slight whistle during switching (opening or closing the circuit). This brief and punctual noise (a few seconds during each on/off cycle of the thermostat) is normal for models equipped with bimetallic thermostats.
Whistling from micro-leaks on fluid models
On a fluid-filled towel dryer, a whistle may indicate a micro-leak at a connection through which pressurized fluid escapes as steam. This type of noise is usually accompanied by a wet trace or a limescale deposit around the affected connection. This is the only type of whistle that requires rapid intervention to prevent deterioration of the appliance.
Abnormal electrical whistling
A loud and continuous electrical whistling, sometimes accompanied by a slight burning smell, may indicate a problem with an internal electrical component (failing capacitor, loose connection creating electrical arcs). In this case, turn off the appliance immediately and have it checked by a technician before any further use.
⚠️ Warning sign: If the whistling is accompanied by a smell of burning, hot plastic, or ozone (a pungent odor characteristic of electrical arcs), immediately turn off the appliance at the circuit breaker and do not put it back into service without professional verification. These combined symptoms can indicate a serious electrical failure.
Hums and vibrations: fasteners at fault
A dull hum or a perceptible vibration when touching the towel dryer or the adjacent wall is almost always related to the appliance's fasteners — a simple cause with a simple solution.
The mechanism of fastener hum
When a towel dryer is properly fixed, the slight mechanical vibrations produced by thermal expansion and fluid flow are absorbed by the fasteners and transmitted to the wall in a dampened manner. If the fixing screws have loosened over time (a normal phenomenon on all appliances subjected to thermal cycles), a microscopic play appears between the appliance and the wall support. This play transforms normal vibrations into a low-frequency hum or click amplified by resonance.
The diagnosis
To confirm that the fasteners are at fault, firmly press your hand flat on the front of the appliance while it is operating. If the hum decreases or disappears under the pressure of your hand, the fasteners are indeed loose.
The solution: tightening the screws
Turn off the appliance and let it cool down. Using an appropriate wrench or screwdriver, tighten all wall mounting screws and all internal structural screws of the appliance accessible without disassembly. If some screws can no longer be tightened properly (torn anchors, damaged thread), replace them with screws and anchors of a slightly larger diameter.
Anti-vibration washers
If the hum persists after tightening the screws, insert rubber or silicone washers between the appliance's fasteners and the wall. These washers dampen residual vibrations and generally eliminate the hum even on appliances with slightly worn fasteners.
Rumbling and loud noises: warning signs
Certain noises, less frequent but more concerning, must be taken seriously and not ignored.
Hydraulic water hammer
On hydraulic (hot water) towel dryers, a dull and sudden bang ("bang") when the water circulation starts or stops is characteristic of water hammer — a pressure wave created by the abrupt stopping of water circulation. This phenomenon can damage connections and welds over time. The solution involves installing a hydraulic water hammer arrester on the supply piping — to be entrusted to a plumber.
Overheating rumble
A dull and continuous rumble accompanied by excessive heat on the bars (above 70°C, too hot to keep your hand on) may indicate a failure of the safety thermostat, which no longer cuts off the heating element at the right time. This symptom requires urgent intervention — a constantly overheating appliance poses a fire risk.
Loud, sharp electrical click
A sharp electrical click (different from a mechanical expansion click due to its electrical nature and intensity) may indicate an internal electrical arc related to a faulty connection or an end-of-life electronic component. Immediately turn off the appliance and have it checked.
How to bleed a fluid-filled towel dryer
Air bleeding is the most frequently required intervention on fluid-filled towel dryers. Here's how to do it.
Identify the bleeder valve
All fluid-filled towel warmers have a bleed screw (or automatic air vent) usually located on the upper part of the appliance, on a vertical upright or on an upper connection. This screw, often small (6 to 8 mm), is the point through which air escapes during bleeding. Consult your appliance's manual to precisely locate this bleeding point.
Bleeding Procedure
Equipment: open-end wrench or screwdriver suitable for the bleed screw, small container to collect any fluid drips, absorbent cloth.
Step 1: Turn on the towel warmer to maximum power and wait 20 to 30 minutes for the fluid to heat up and circulate well.
Step 2: Position the container and cloth under the bleed screw.
Step 3: Slowly unscrew the bleed screw by a quarter turn. You should hear a hiss of air followed by a fluid-air sputtering. Keep the screw slightly open until only fluid flows without air bubbles.
Step 4: Immediately retighten the bleed screw. Check for any residual leaks.
Step 5: Wait 10 minutes and check that the gurgling has disappeared. If necessary, repeat the operation.
After Bleeding
Check that all bars heat evenly by touching them after 30 minutes of operation. A bar that is still cold after bleeding may indicate a residual air pocket — repeat the bleeding, slightly tilting the appliance to dislodge stubborn bubbles.
⚠️ Precaution: The heat transfer fluid in an operating towel warmer can reach 60 to 80°C. Protect your hand with a thick glove when handling the bleed screw, and position the container before opening the screw to avoid any spray of hot fluid.
Diagnostic Table: Noise → Cause → Solution
| Type of Noise | Moment | Probable Cause | Severity | Solution |
|---|---|---|---|---|
| Sharp cracking sounds | Start-up / Shut-down | Thermal expansion | ✅ Normal | None |
| Gurgling / bubbling | During operation | Air in the fluid circuit | ⚠️ Minor | Air bleeding |
| Slight continuous whistling | During operation | Resistor vibration (50Hz) | ✅ Normal | Monitoring |
| Sudden loud whistling | During operation | Fluid micro-leak / electrical arc | ❌ Urgent | Turn off + technician |
| Dull humming | During operation | Loose fixings | ⚠️ Minor | Tighten screws |
| Sudden dull thump | Start-up / Shut-down | Water hammer (hydraulic) | ⚠️ To be addressed | Water hammer arrestor (plumber) |
| Rumbling + overheating | During operation | Faulty thermostat | ❌ Urgent | Turn off + technician |
| Loud electrical crackling | Variable | Internal electrical arc | ❌ Urgent | Immediate shutdown + technician |
When to call a professional?
The vast majority of noises from an electric towel warmer are harmless or can be resolved by yourself. Here are the situations that absolutely require the intervention of a qualified professional.
Urgent intervention required
- Noise accompanied by a burning smell (electrical, plastic, ozone)
- Noise accompanied by abnormal overheating (bars impossible to touch)
- Noise of a sharp and loud electrical cracking type (different from expansion cracks)
- Noise accompanied by a visible leak of fluid or water
- Any noise appearing after an intervention on the electrical installation
Recommended intervention (non-urgent)
- Whistling that has gradually intensified over the past few weeks
- Gurgling persisting after two unsuccessful bleeding attempts
- Hydraulic water hammer occurring at each start-up
- Humming persisting after all fixings have been completely tightened
🌿 Good to know: For towel warmers under warranty (generally 2 to 5 years depending on the manufacturer), any abnormal noise justifies contacting the manufacturer's after-sales service before attempting any intervention yourself. A repair carried out by a non-professional may invalidate the remaining warranty.
Listening to your towel warmer: a diagnosis accessible to all
The noises of an electric towel warmer speak, provided you know how to listen to them. Cracks on start-up, humming from fixings, gurgling air in the circuit or electrical whistling: each sound has its signature and its meaning. The vast majority of these noises are normal and require no intervention — some others are warning signs that deserve immediate attention.
Use the diagnostic table in this article as a reference when a new noise appears. If in doubt about the nature of a noise or if you observe associated symptoms (smell, excessive heat, leak), do not hesitate to turn off the appliance as a precaution and consult a qualified technician.
Frequently Asked Questions
My towel warmer clicks when it starts, is that normal?
Yes, it's perfectly normal in the vast majority of cases. The clicking sounds during start-up are caused by the thermal expansion of the metal bars as they heat up. These micro-movements of expansion are released as clicks at the contact points between metal parts. This phenomenon is inevitable on any metal appliance subjected to thermal cycles and presents no risk. It is simply more pronounced when starting after a long period of inactivity (first start of the winter season, for example).
How do I stop gurgling in a fluid-filled towel warmer?
Gurgling is caused by air bubbles trapped in the fluid circuit. The solution is bleeding: turn on the appliance at full power for 20-30 minutes, then slightly open the bleed screw (usually located at the top of the appliance) until only fluid flows without bubbles, then close it. If you cannot find the bleed screw, consult your model's manual. If bleeding fails after two attempts, contact the manufacturer's after-sales service.
Does a noisy towel warmer consume more electricity?
It depends on the cause of the noise. Thermal expansion clicks and fixing hums do not increase consumption. However, air gurgling in a fluid-filled circuit reduces the thermal efficiency of the appliance, which can lead to slightly higher consumption for the same heating result. Bleeding the air restores normal efficiency and can therefore have a positive effect on consumption.
My towel warmer makes a noise by banging against the wall — what should I do?
This noise indicates that the appliance is no longer perfectly flat against the wall and vibrates against it during thermal cycles. First, check that all mounting screws are tightly secured. If the problem persists, place rubber or silicone washers between the appliance's fixings and the wall to absorb vibrations. In cases where the wall plugs are damaged, it may be necessary to re-fix the appliance with new plugs in a slightly offset location.
The noise from my towel warmer has suddenly changed — what should I do?
A sudden change in the nature or intensity of noises from a towel warmer should always be investigated. Start by turning off the appliance and visually checking for any leaks, burn marks, or deformation. If the noise is accompanied by an unusual smell or abnormal heat, do not put the appliance back into service without professional verification. If the noise is simply different but the appliance appears to be functioning normally, use the diagnostic table in this article to identify the probable cause and determine if intervention is necessary.
