Hands-On: Replacing the Oven Thermostat and Capillary Tube

⚠️ SAFETY FIRST: IMPORTANT

Replacing a thermostat requires handling delicate components like the capillary tube. Ensure the oven is completely disconnected from the power. Be extremely careful not to kink or bend the capillary tube sharply, as this will break the internal seal, release the gas, and render the new thermostat useless.

If your testing has confirmed that the thermostat is out of tolerance or faulty, it’s time for a replacement. This process involves navigating from the front control panel to the rear of the oven cavity.

Step-by-Step Removal

Gain Access: You’ll typically need to remove the front facia (control panel) and the rear wiring covers. On some models, you may also need to unscrew and slightly lift the hob top.

Locate the Switch: Find the oven selector switch. The thermostat unit is usually attached to the rear of this switch. It is often held by a "push and twist" mechanism or small clips.

The Probe Path: Trace the thin metal capillary tube from the switch to where it enters the oven cavity. It may be secured by zip ties or clips along the chassis—carefully remove these.

Extract the Probe:

Internal Mount: Most probes are held inside the cavity by a simple screw or metal tabs.

Element Mount: On some models, the probe is tucked inside a metal sheath on the heating element itself. You may need to gently open the end of the sheath to slide the probe out.

Refitting Tips

The "No-Kink" Rule: When feeding the new capillary tube through the oven body, use wide, sweeping curves. A single sharp bend (kink) will ruin the part.

Secure the Probe: Ensure the probe is positioned exactly where the old one was. If it’s loose or in the wrong spot, it won't accurately sense the cavity temperature, leading to poor cooking results.

Tighten Terminals: Ensure the electrical connections to the new thermostat are tight to prevent heat buildup.

You will need to gain access to the rear of selector switches and to the rear of the oven cavity, on this model its a few screws to hold rear wiring covers, remove the from facia and all switches then unscrew the hob top to pull it out of the way slightly. You may need to look at your models manual for this information.

On this model the upper thermostat capillary tube is inside the heater element which makes it a bit harder if yours is this sort you need to open up the end of the capillary tube sleeve and remove the probe from inside of it , on most oven its usually inside oven cavity held but one screw or two tabs you must free it from usually very easy. One free pull it out and follow the wire / tube connecting it back to switches but do not bend it to much and do not kink it. You may also need to unclip it or cut zip lock ties. But on this one it was not needed.

Next go to the switch with the thermostat connect and you either just pull it free from switch sometimes it may need to be twisted.

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Gain access to rear of cavity and to the switch panel 

This is the oven selector switch with thermostat unit fitted to rear of it 

They can be tight but will either pull free or need to be twisted to release you can tell by looking or manufacturer information.

Trace the wire / tube back to when it goes into the oven cavity

 

This one is an upper grill / oven element and the probe of thermostat goes into the

element , the element has a metal sheath the probe fits into, you have to open up the end to remove it 

and then squeeze it tight after refitting to prevent it coming out.

Some ovens have the element inside the cavity either screwed or clipped in place 

See video of this process below