Should I Turn My Boiler Off in the Summer?

The main utility of a boiler is to provide space heating and hot water. During the colder part of the year, it must work continuously without a break. As summer sets in, the heating function of a boiler may no longer be required. However, as far as hot water in taps is concerned, it is perhaps a year-round necessity in a home. You may want to consider turning off your boiler to reduce energy consumption. Doing so may also deprive you of hot water. So, quite a tricky situation! Then what’s the best option?

Completely turning off a boiler in summer has some benefits, but at the same time, its disadvantages cannot be ruled out. Hence, answering the popular question, "Should I turn my boiler off in the summer?" needs an in-depth evaluation to reach a workable solution. However, before that, it is necessary to understand how a boiler works and how much energy it consumes to operate. 

Working of a Boiler – A brief Overview

Without going into technical details, let’s try to understand how a boiler works. A boiler is primarily required to perform two basic functions:

• Space Heating, through a central heating system.
• Supply of hot water for domestic use, such as taps, showers, dishwashers, and washing machines. 

• Process of Space Heating

Space heating is the prime function of a boiler. A summarized step-wise process of heating is as under:

• The thermostat is pre-set at a certain temperature that matches the required level of heating in a room. 
• When the room temperature falls below the preset heat level, the thermostat activates the boiler heating system, causing it to start heating the room. 
• The burner is ignited, enabling the boiler to start heating the water in the heat exchanger (a component of the boiler). Most of the boilers use gas for heating. However, some boilers also use electricity or oil for this purpose. 
• When the water heats up, it is circulated through a pump to the network of radiators. Radiators are installed at various locations, as required by the building. The heated water is transported to these radiators through a network of pipes that usually run underground, across the entire building, to reach all the radiators. 
• Radiators emit heat into the room. When the air passes over the heated water in the radiators, it becomes warm, which in turn raises the internal temperature of the room. 
• The heated water then gets colder and is pumped back to the boiler for heating again.
• The heating system keeps on circulating heated water to the radiators until the required room temperature is achieved. At this stage, the thermostat signals the boiler to stop heating water. 
• The cycle continues throughout the day and night, during the entire winter.  

• Supply of Hot Water

The second function of a boiler is to supply hot water to taps, showers, washing machines, and dishwashers. Usually, the boilers are of two types. When it comes to hot water supply, the combi boilers and regular boilers. 

Combi Boilers (Combination Boilers)

Most of the boilers these days are combination boilers. The process of supplying hot water through a combi boiler is as under:

• It heats the water for supply in hot water taps/showers, only “on demand”, hence no separate water storage tank is required.
• When a hot water tap or shower is turned on, the boiler detects the demand for a hot water supply. Resultantly, it diverts energy towards heating the water instantly. 
• When the hot water tap is turned off, the boiler stops heating the water. 

This type of hot water supply is energy-efficient and ideal for small homes, where demand for hot water is less and intermittent. 

Regular Boilers (System Boilers)

Regular or System Boilers are suitable for larger homes, where more than one bathroom or kitchens use hot water. The process of heating water by this type of boiler is as under:

• Water is consistently heated and stored in a hot water tank. 
• When a hot water tap is turned on, the water stored in the hot water tank is diverted to the tap.
• Hot water is available for use at all times. 

Even if hot water is used or not, the system boiler continues to heat and store hot water in the water tank. When the temperature of the heated water drops, the boiler restarts heating it. The result is a continuous supply of hot water, but it consumes a significant amount of energy, even when the hot water is not in use. 

Important Components of Boilers

• A heat exchanger is a component that heats the water in the boiler for onward supply to the heating system and hot water supply system.
• The thermostat is used to control the required temperature level. When the temperature drops, the thermostat signals to boiler to start heating the water. When the desired temperature level is reached, the heating system turns off.
• The expansion vessel and Pressure Relief Valve are designed to maintain a stable pressure, ensuring the safe operation of the boiler. 
• A Diverter Valve is used in combination boilers to switch between radiators for space heating and heating water for supply to hot water taps. 

Energy Consumption of a Gas-Powered Boiler 

• A combination boiler ideally consumes energy somewhere between 8,000 to 17,000 kWh annually, out of which:
  • Approximately 70 to 85% of the energy is used for space heating.
  • 15 to 30% is used for the supply of hot water.
• The annual energy consumption of a Regular or System boiler ranges between 10,000 to 20,000 kWh. 

The above comparison shows that the energy consumption of regular boilers is considerably higher because they must continuously heat the water. It is estimated that a standard home with three bathrooms consumes 12,000 to 15,000 kWh annually, for space heating and hot water supply. 

Is it Okay to Turn the Boiler Off in the Summer?

Once the process of heating and supplying hot water through different types of boilers is understood, it will be easier to find the correct and workable answer to this important question. The comparison of energy consumption for space heating and hot water supply can also be a useful parameter in making the correct decision on whether to turn off the boiler in summer or not.

To reach a correct decision, you need to consider the following factors:

• Utility of a Boiler in Summer

The first thing you need to consider is whether you need your boiler in the summer. In most cases, a boiler is used simultaneously for space heating and hot water supply. If you use your boiler only for space heating, the decision would be straightforward; you can turn off your boiler in summer. But if the boiler is also used for hot water supply, you cannot turn it off completely, even during summer. So, the decision should be taken carefully, considering this factor. 

• Energy Saving Options

Energy consumption of a boiler, as explained above, is yet another very important factor that needs your attention. More than 70% of the total annual energy is consumed for space heating. Turning off only the space heating function of the boiler can save a considerable amount of energy, while still providing hot water for taps and showers. 

However, most modern boilers come equipped with features that enhance energy efficiency. This type of boiler uses less energy when you only require hot water, as per your specific needs. So, instead of completely turning off your boiler, you can save energy by:

• Adjust the thermostat to a lower temperature. Alternately, you can also switch it to only the hot water function.
• Some latest versions of the boiler also provide the facility of Summer or Holiday settings. Using this function, you can minimize the energy usage, as when this mode is turned on, only essential functions remain active. 

• Risk of Damage or Seizure of Boiler Components

Boilers have some moving components and valves. There is a significant possibility of seizing or damaging such parts if the boiler is left out of operation for an extended period. Hence, completely turning off the boiler for the entire summer may have consequences, in the form of huge expenses on getting it operational again. 

Alternately, you can follow these steps to avoid the risk of seizing or damaging various components of your boiler. Turn on the heating function of your boiler for 10 to 15 minutes, at least once a month. Occasionally, turn on the hot water taps so the internal parts of your boiler remain active. 

• Cost Saving on Maintenance and Servicing

Summer is an ideal time to get the boiler comprehensively serviced and maintained. Gas-safe registered engineers are usually less busy during this season; hence, they are easily available at a comparatively lower price. So, while considering turning off your boiler in summer, also think about saving some cost on maintenance and servicing. Completing it in the summer also provides peace of mind, as the system will be ready for use instantly at the onset of winter. 

Best Practice During Summer

• Use the Summer or Holiday functionality, if available in your boiler, to save energy.
• Turn on the hot water taps regularly to keep the system operational.
• Keep it operational throughout Summer at low temperatures, if there is a possibility of fungus growth due to dampness. 
• Turn on your boiler for a few minutes, occasionally, to keep it in running condition, especially the moving parts. 

Conclusion

A boiler is not only required in winter, but it also has its utility in summer, especially when you need it for hot water supply in taps and showers. The decision to turn it off completely during the summer requires a careful analysis of various aspects, including summer requirements, energy savings, protection of the boiler from potential damage, and the need for maintenance and servicing. 

Considering all these factors, the best option might be to use the summer or holiday function, if available in your boiler. Alternatively, you can turn it off, but make sure to turn it back on for at least 10 to 15 minutes once a month. In areas where the possibility of dampness and fungus growth is higher, keeping the heating system active at a low temperature throughout the summer season might also be a good option. 

The final decision on whether to keep the boiler turned on or off during summer depends on your priorities and prevailing circumstances. However, protecting your boiler from potential damage or seizing of moving components should be given top priority to avoid extra repair costs.