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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
    in the last week
  • 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 week 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
    in the last week
  • 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 week ago

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  • 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

  • Water is Leaking on my Furnace

    Water falling on to the furnace can harm your heating unit by affecting the control boards and other components enclosed in the furnace. There can be many causes to the water overflow, but the most common cases in the summer is the ice build up inside the evaporator coil due to low refrigerant level. Water build up can also be due to the evaporator coil having a crack on the base, if this is the case contact us by booking an appointment or call us today to have a technician come have a look at your unit and repair this issue before it causes excessive damage.  

  • What is a mini-split?

    By definition, and simply put, a “Split System” is a heating and air conditioning system which has two main components, the indoor unit and outdoor unit. In short, the indoor unit absorbs heat energy in the cooling mode, and the outdoor unit rejects the very heat absorbed by the indoor unit. And the cycle is repeated until the set temperature is met. Although the indoor and outdoor units are located in physically different, hence “split” locations, they are connected and operate as, one system; continuously circulating refrigerant liquid and vapor by means of interconnecting, dehydrated copper refrigerant lines, commonly referred to as a “Line Set”.

  • 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!

  • What are mini-split advantages?

    Just as the name implies, a “mini-split” system is a “split system” however available in smaller capacities, for single room to whole house conditioning. Mini-split systems may range from as small as 9,000 BTUh per hour, comparable to say, a small window AC unit, for individual room use, up to 4 and 5 ton capacities for “Room By Room” (also known as “Zoning”) and whole house conditioning. With near universal design, mini-splits are “heat pumps” which provide both heating and cooling for a home. Here are key advantages when compared to traditional split systems:

    Efficiency- Mini-splits are highly engineered systems which offer attractive operating efficiencies, in many instances, eligible for utility company rebates.
    Heat Pump- Most mini-split systems are heat pumps, providing year-round comfort.
    Solar friendly- Due to very low power requirements, mini-splits are an ideal complement to “Net Zero Energy” homes, or any home using renewable power.
    Carbon footprint- Mini-splits are 100% electric, with zero operating emissions of any type.
    Zoning- Most mini-split manufacturers offer systems capable of room-by-room “zoning”, to account for peak demands of a room based upon construction type, exposure orientation and usage.
    Variable capacity- Mini-splits are typically DC inverter driven. That is, a variable speed compressor which modulates in proportion to instantaneous demand. Most conventional split systems, by comparison, operate with an ON-OFF strategy. (Would you use an ON-OFF switch as the accelerator in your vehicle?)
    Location, Location, Location!- Mini-split outdoor units are compact; they can be located far away from noise-sensitive areas, such as bedrooms and home offices. Mini-split indoor units have the ability to be installed where conventional systems cannot.
    They’re perfect for additions and remodels where access to current HVAC system is difficult to access.
    Modern mini-split systems are remarkably quiet; in fact, many times their operation is unnoticed by the end user.

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