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Intergas Boiler Fault Code 13


The Intergas fault code 13 relates to the S1 sensor, sensing a fault on the heating exhanger and here we have Q & A. We could also offer you a service by you clicking on our emergency boiler repair booking.


The Intergas Boiler Fault Code 13 Error Common Q & A


Just below, we have a list of common questions relating to the fault code 13 on the Intergas Boiler.

Intergas boiler error code 13
  • What does fault code 13 mean on Intergas boilers?
  • Can’t I just reset my boiler myself, to fix fault code 13?
  • How will my boiler engineer know if the S1 sensor is faulty on my boiler?
  • How could the PCB contribute to fault code 13 being displayed?
  • How can my boiler repair company check the PCB for faults?
  • If I need to replace the PCB, how much will a heating company charge?
  • My boiler engineer thinks that the pump is leaking, could this have broken the PCB?
  • My boiler repair company thinks a circulation fault is to blame, what is this?
  • What could cause a circulation issue within the heat exchanger in my Intergas boiler?
  • My boiler engineer thinks there’s a problem with the heat exchanger, how much will it cost to replace?

What does fault code 13 mean on Intergas boilers


If your Intergas boiler is showing fault code 13 on the display panel, there’s a S1 sensing fault on the heat exchanger.

The idea behind the fault code, is to narrow down the list of potential problems for your boiler engineer. This makes the fix much quicker and therefore, much cheaper.

After the fault code is displayed, it’s also likely that the boiler locks out; it won’t work until the problem has been fixed by your boiler repair company, and then the appliance is reset.

Can’t I just reset my boiler myself, to fix fault code 13


The reset function on your boiler won’t fix the problem. Your boiler has locked out for a reason. And in this case, it’s most likely the lockout has occurred in order to preserve internal components.

You’ll need to call a heating repair company. They’ll send a Gas Safe registered heating engineer to pin-point and fix the problem. Once fixed, they’ll reset the boiler on your behalf, and this will clear fault code 13 from the display panel.

How will my boiler engineer know if the S1 sensor is faulty on my boiler


The first thing for your boiler repair company to check, is the S1 sensor. They’ll need to determine if the problem is due to an external force, causing the temperature and flow at the S1 sensor to be incorrect. If this is the case, the S1 sensor is doing its job properly. The idea behind the sensor is to inform the printed circuit board (PCB) when there’s an issue, and it does so by constantly sending readings.

If the S1 sensor isn’t faulty, then your boiler engineer will need to narrow down the root cause of the problem by checking the:

  • PCB for an electrical fault
  • Heat exchanger for a circulation fault.

How could the PCB contribute to fault code 13 being displayed


When any fault code presents itself on a boiler, the PCB needs to be checked. That’s because it’s the PCB that gives and receives readings and commands to all electronic boiler components, and that includes the S1 sensor.

If the PCB were to be faulty, it may not be interpreting the readings being given by the S1 sensor or might not be receiving them at all. At this point, the PCB would assume there’s a problem within the heat exchanger. To preserve the heat exchanger, it will lockout the boiler and display a fault code.

The problem with the PCB could be anything from intermittent power, through to loose connections and damaged wires.

How can my boiler repair company check the PCB for faults


After concluding that the S1 sensor isn’t to blame, your Gas Safe engineer is going to start testing the PCB. As we mentioned above, they’ll be testing wiring, connections and the PCB itself.

Any loose connections need to be secured, and damaged wiring will need to replaced. On some occasions, the PCB unit might be the issue, and it will need to be replaced.

If I need to replace the PCB, how much will a heating company charge


The PCB on Intergas boilers is one of the most expensive components to replace. Typically, we’d expect the replacement price including parts and labour, to be in the region of £450.

If this is the cause of fault code 13 being displayed on your control panel, it’s likely your boiler engineer is going to want to check other components in your boiler. £450 is an incredible amount to spend on a repair, especially when replacement boilers can be fitted from £1,800.

Assuming other components are in good condition, and even more so if other boiler parts are still under warranty, it makes sense to repair the boiler rather than replacing it.

My boiler engineer thinks that the pump is leaking, could this have broken the PCB


If your boiler isn’t over 5-10 years old, it’s likely there’s been a catalyst that’s caused the PCB to fail. And, one of the biggest catalysts for boiler parts breaking sooner than they should, is water damage.

The pump on your boiler has seals that over time, can degrade. If the boiler is put under excess strain, the pump is on too high a speed setting or there’s a blockage, these seals will eventually give way.

And, this is why we suggest having your boiler engineer check all components in your boiler. The PCB is one of the most fragile parts. If this has failed due to water damage from a leaking pump, its likely other parts are going to follow suit, and replacing the boiler may be a better option than a repair.

My boiler repair company thinks a circulation fault is to blame, what is this


If the S1 sensor is giving readings that are correct, but are outside of the boiler’s working tolerance, a circulation fault could be to blame. When water can’t travel around the heating system correctly, circulation is restricted. This could result in parts overheating in your boiler. More importantly, it might mean that taps, showers and radiators don’t get up to temperature quickly enough, or at all.

A circulation fault could occur for several reasons. But in this case, it’s most likely that the problem stems from the heat exchanger.

What could cause a circulation issue within the heat exchanger in my Intergas boiler


If you’ve got a circulation issue that stems from the heat exchanger, it’s likely that limescale in to blame. Just like dishwashers, boilers can get a build-up of limescale within the appliance. We see descaling solutions for dishwashers advertised, and there are similar products available for boilers, but the cost savings due to increased efficiency and reduced repair costs are far greater.

The first thing your boiler engineer needs to do, is flush the system of any debris, and this isn’t just limescale. Your boiler will also build up heating sludge; rust from towel rails, radiators and even pipework.

By flushing the system at heat using a heating cleaning chemical, this will help to remove most limescale and heating sludge.

Once finished, they’ll top up the system with water, bleed radiators, and dose the system with inhibitor. The inhibitor breaks down heating sludge and limescale into small enough chunks that a scale reducer filter and a magnetic boiler filter, can catch them.

With each boiler service, your engineer will be able to remove limescale and sludge from these filters, leaving them free to catch more.

My boiler engineer thinks there’s a problem with the heat exchanger, how much will it cost to replace


Not all boiler repairs are quick, simple or cheap fixes. If the circulation fault relates to a broken heat exchanger, you’ll need a replacement.

Costs will vary depending on the exact Intergas boiler that you own. But you should expect to pay somewhere in the region of £450, including parts and labour.

Other Intergas boiler issues


For more boiler issues regarding the Intergas boiler then please visit the Intergas Boiler Problems And Cures page.