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Can My Boiler Overheat? 5 Causes Of An Overheating Boiler

March 17, 2021

Can My Boiler Overheat? 5 Causes Of An Overheating Boiler

The short answer is yes, your can boiler overheat. A boiler overheating is not unusual. However, this does not mean that you should ignore it since it can lead to severe problems like causing damage to other parts of the unit. In order to prevent such an occurrence, contact A-Plus Quality for boiler maintenance in the Greater Toronto Area if you notice the warning signs of an overheating boiler.

Causes of Overheating in Boilers

There are a variety of causes that lead to overheating of boilers. Luckily, at A-Plus Quality we offer boiler maintenance the Greater Toronto Area and surrounding regions to help prevent the causes of overheating. Here are some common causes of an overheating boiler:

1. High-Pressure

High pressure in the boiler acts as the primary cause of overheating. Usually, the high pressure might be a result of other malfunctions in the unit. The best way to solve this problem is to either relieve the pressure from the boiler or find and correct the malfunction causing the increase in pressure.

2. Failed Thermistor

In other cases, a boiler may overheat as a result from a failed thermistor. A thermistor's main task is to inform the PBC whether the temperature demand is less or more than the production. Therefore, when it fails, more fuel is provided. This causes the water to become too hot, leading to the boiler overheating.

3. Blockages

When a boiler overheats, it may be a result of blockages caused by central heating sludge. The central heating sludge typically forms inside the valves, radiators, and pipes and may clog the entire system. This clogging leads to back pressure. Overheating might also result from condensate blockages, which occur when the condensate pipes freeze due to cold weather.

4. Overheated pump

On some occasions overheating of the boiler might emanate from an overheated pump. Pumps must remain warm instead of hot. If a pump becomes too hot, it might lead to a seizure of the internal components and cause the boiler to overheat. The solution to this problem is to contact A-Plus Quality for boiler maintenance, or boiler repair in the Greater Toronto Area, for a professional replacement of the pump.

5. Limescale on the Heat Exchanger

Limescale forms in areas with water and is common in places containing hard water. As this limescale builds up on the heat exchanger, it may create several hotspots. These hotspots spike the temperature of the water leading to an overheated boiler.

If you have noticed any signs that your boiler is over heating, A-Plus Quality can send over one of our certified technicians to inspect the issue and provide boiler maintenance or boiler repair in the Greater Toronto Area and surrounding regions. Contact us today to schedule an appointment. 

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Client Testimonials

  • First experience was on New Year's Day, 2020, when furnace stopped. Called A-Plus and they had a rep (Jack) out quickly. He did some troubleshooting. He wasn't giving BS. Gave me options on repairing or replacing. Non-biased, no pressure. I chose replace and it was done the next day. Good experience all around. Second experience was early March, 2021 when a harsh chemical smell emanating from the furnace room, and pushed through the HVAC venting, permeated the house. Very concerning. Was late night, called A-Plus, immediately answered and suggested some safety moves for the evening. Booked a visit for the morning. Jack again came and assessed the issue and advised where the smell came from (outside). Again, very professional, quick, no BS, good guy. Completely satisfied with the service after often being given the BS treatment from other service providers for the house. Would definitely recommend.

    Daniel Colombo
    a month ago
  • A Plus Quality Inc were absolutely AMAZING! I changed my furnace, AC, and humidifier. They were quick, efficient, professional and did an outstanding job. I definitely recommend them to everyone!

    Paul D
    3 weeks ago
  • From the moment we called A Plus, until our heat was restored, the customer service was excellent! Polite and caring over the phone. Considerate and efficient technicians at the service end. Highly recommend.

    sue casey
    a month ago
  • A Plus Quality did a wonderful job installing our new Carrier heating system and ecobee smart thermostat. The technicians were courteous, professional and followed the health and safety protocols in regards to Covid-19. Thank you for a job well done!

    Patri A
    a month ago
  • what an amazing company, very friendly well experienced in the trade. they have lots of knowledge and the take all percostion of covid when coming into my house. they are also very clean and get the job done right. I will definitely be going to them again. I highly recommend for everyone to use a-plus quality.

    Gianluca Altobello
    a month ago

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  • Why is there ice building up on the copper pipes?

    There can be many reasons why the refrigerant pipes are freezing up but the most common issue is low refrigerant levels. If your AC unit has ice buildup turn off the unit for at least 4 hours and call us at 416-410-0337

  • What is a heat pump?

    Heat pumps use electricity to move heat from a cool space to a warm space, making the cool space cooler and the warm space warmer. During the heating season, heat pumps move heat from the cool outdoors into your warm house and during the cooling season, heat pumps move heat from your cool house into the warm outdoors. Because they move heat rather than generate heat, heat pumps can provide equivalent space conditioning at as little as one quarter of the cost of operating conventional heating or cooling appliances.

  • Furnace is blowing cold air in Winter?

    This can be due to Ignition lockout, sometimes could be resolved by resetting the power  and if this does not resolve the issue you should contact a certified gas technician from A-Plus Quality to get this problem resolved!

  • Most common Boiler Issues

    - Boiler fails to ignite
    - Low pressure
    - Strange Noises
    - Boiler is not responding to the thermostat
    - Cold Radiators
    - Boiler leaking or dripping
    - Boiler cycling very fast
    - Available Hot water but No Heat

  • Why should I maintain my Furnace or AC?

    An annual maintenance will extend the lifetime of your heating and cooling unit. The technician will diagnose and repair any problem with the unit before it fails, so you won't need to worry about any problems when the weather gets very hot in the summer or extremely cold in the winter.

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