Cost Advisor

Hydronic Central Heating Service: Common Issues

March 15, 2022

Central heating is the most effective and efficient way to heat the whole house, so long as it is regularly maintained.

Hydronic central heating provides the best quality of heating possible. Hydronic systems work by heating water or glycol that is then piped either under the floor, or through the radiators. These systems typically use a gas boiler, hydronic systems provide radiant heat which when compared to an air ducted system or a heat pump, it is no contest which feels better. Radiant heat heats the room and all the objects in the room, so that if a door is opened and a draft comes through, it will not dramatically alter the temperature of a room, whereas with a heat pump or air ducted system, drafts will dramatically alter the temperature of the room.

With all central heating systems regular maintenance is required to keep the system working efficiently and effectively, for this blog we will be discussing Hydronic central heating systems and what issues can occur if left serviced.

Issues that can happen with Hydronic Central Heating

  • High gas usage. Much like a cars engine, regular maintenance is required to ensure the efficiently of the system, if you are using a lot more gas then you use to, it might be time to get a service, it is recommended to service the central heating system once each year, either before or after the start of the most used season.
  • Hot Spots or Cold Spots. You may notice it with underfloor heating when you walk around the house and parts of the house feel warmer than others, or you may even find spots on the floor that are cold. With Radiators you will notice it when you run your hand across the radiator, parts of the radiator may feel hotter or colder than others. Typically, hot and cold spots are only noticeable on underfloor heating systems but still can be an issue with radiators uncommonly. With hot or cold spots on a radiator, it can even be caused if the flow and return connections to the radiator being installed incorrectly or the wrong way around. What usually causes hot and cold spots is when the inhibitor is not regularly changed, sludge can build up, or rust can form causing the water to not flow evenly through the central heating pipe work or radiator. Another cause of hot or cold spots could be related to the Manifold (the manifold is where you adjust the temperature to each zone of the underfloor heating) without going into too much detail about how a manifold works, they basically adjust the flow of water that goes though each underfloor zone based on the heat loss to ensure an even temperature though each of the underfloor zones, so if you are experiencing issues with one zone being a lot hotter than another, the manifold could be the issue.
  • Inconsistent temperatures around the house. inconsistent temperatures can be caused by a lot of reasons; problems with the thermostat/s around the house, issues with the boiler or heating device not providing a consistent temperature or even if the system is just not configured correctly for the space.
  • Noise coming from boiler or heating device. If the boiler is making funny noises, or just any noticeable noise, ask yourself when the last time you had the boiler serviced was, is the pressure of the boiler set correctly? Boilers need to be serviced correctly and regularly to ensure the safety and functionality
  • Gas smells or smoke coming from the flue of the boiler. If you notice any strong smell of gas coming from the boilers flue (or the boiler) this will mean you are wasting gas! If the boiler is not working efficiently, you could be piping gas straight out the flue wasting potential fuel that could have been used to heat the house. Smoke should never be coming from the flue of the boiler, steam is very normal, but any form of black smoke is a massive red flag and should be addressed immediately.
  • Beeping or Error codes on the boiler. Any form of beeping or error codes will be indicating what is going wrong with the boiler, in some cases the boiler may give a code that informs you exactly what part of the boiler to inspect, be cautious as in some cases the boiler could throw a code which is completely unrelated to the real issue
  • Boiler pressure too low or too high. Most boilers have a pressure gauge, within the pressure gauge there will be an operating zone, typically marked with green, if the pressure gauge is showing a reading outside this zone, do not use the boiler until the issue is fixed
  • No hot water. As boilers are a one of the most efficient means to heat water, a lot of central heating systems have the hot water cylinder plumbed in so that the boiler can heat the water for the hot water cylinder, if you are experiencing no hot water and your cylinder is connected to the boiler, you could have an issue with the diverting valve.

If you are experiencing any of these issues (or any unlisted issues) we always recommend getting the central heating system serviced before addressing the issues, as a lot of the time the issue can become resolved throughout the service. There are a lot of issue that can happen with central heating systems if left un-serviced, that’s why it is recommended to have the system serviced every year to ensure the efficiency and the effectiveness of the system.

We have lots of servicing plans available, with our team of central heating experts, and over 15 years of experience, you are in the right hands with us, whether you have a small central heating system, or large industrial system, we can make a servicing plan to suit. Check out some of our residential system deals here.

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