Condensing gas boiler – which type should you advise the customer when installing heating?

Added: Tuesday, 11/22/2022


Choosing the right single-function condensing boiler or dual-function boiler can help reduce the costs of heating the building, which in some cases constitute up to 90% of the operating costs of the entire house . Thermal modernization can make the bills, among others, costs for central heating will decrease - one of the elements of this process is the replacement of the heating source. What is the difference between single- and dual-function boilers and which model should the client advise when installing heating? We cordially invite you to read the entire text.

From this article you will learn:

  • what is a single-function boiler,
  • what are the characteristics of a combi boiler,
  • which boiler to choose – single-function or dual-function,
  • what condensing boilers are available in the Onninen offer.

What is a condensing boiler and how does it work?

Condensing boilers , compared to traditional boilers, are characterized by much higher efficiency, reaching up to 109% (thanks to the use of energy captured from exhaust gases, which would otherwise be lost). However, since the boiler is not a perpetual motion machine, calculating its efficiency according to a more modern method results in a result of 98% (compared to 82% in the case of a traditional gas boiler). This is still a fantastic result!

In condensing boilers, in addition to the heat contained in the exhaust gases, latent heat is used - i.e. the energy contained in water vapor . The design of the heat exchanger allows for this. Thanks to condensation, a significant amount of heat is recovered, which in traditional boilers escaped irretrievably through the chimney. The use of the condensation effect allows for significant savings in fuel consumption. The best operating conditions for a condensing boiler are low-temperature installations in which we obtain low temperatures of the water returning to the boiler. The lower it is, the higher the efficiency of the device.

Check out Termet gas boilers at the Onninen wholesaler

A condensing gas boiler is an alternative to a traditional coal-fired furnace, but also to older types of gas boilers . Such models are more economical and ecological, also because they use the entire energy of the burned fuel. In other furnace models, latent heat is lost with the exhaust gases, but gas boilers prevent this loss. In a condensing boiler, water vapor contained in the exhaust gases is condensed through a special cooling process . Thanks to this, the heating system is more efficient and environmental pollution is up to 120 times lower compared to using a traditional coal furnace. It is also worth remembering that all this also has a positive impact on the costs of home heating. Also due to the closed combustion chamber, which avoids cooling of the boiler room (there is no need for a ventilation grille in the wall through which heat escapes).

Check out condensing gas boilers from the Termet brand


Single-function condensing boiler

A single-function gas boiler has one basic task - powering the central heating installation . This model does not have a heat exchanger to heat domestic water, therefore it cannot provide it on its own. To do this, you need a water tank - a separate tank equipped with a coil, which is connected to a single-function boiler. When water from the boiler flows through the coil, the water is heated to the parameters expected by the user. The hot water tank can be placed directly under the boiler, or in the case of a larger capacity, it can be placed next to it.

Please remember that a single-function gas condensing boiler in this version (with a connected heater located on the side or under the single-function boiler) will take up more space.

Combination condensing boiler

A dual-function gas boiler, unlike a single-function one, does not need a separate tank. Combination boilers are equipped with an additional exchanger that allows for instantaneous heating of the amount of water currently required.

The power of a combi boiler depends on the power required to heat domestic hot water. In apartments and smaller houses, the heat demand for heating may be low and amount to 7 kW. For the process to run comfortably, it may be required that the combi boiler has a power of 20-24 kW.

Single-function or dual-function boiler – which boiler to choose? Advantages and disadvantages of both solutions

Which heating boiler should you choose? The answer to this question is not clear, it all depends on individual users and the planned water consumption. The boiler works best in apartments and small single-family houses where there is one bathroom (preferably adjacent to the kitchen) and hot water consumption points are not too far from the boiler installation site. Thanks to this, the waiting time for hot water is shorter.

In turn, in houses with two or more bathrooms, a single-function boiler with a tank is most often used, the capacity of which is adjusted to the size of the family (if everyone in the house uses hot water at the same time, the tank must be large enough). In such cases, it is worth using domestic water circulation, thanks to which hot water will circulate in the pipes, and thus the waiting time for it after turning on the tap will not be too long.

When proposing to the customer to choose one of these two models, it should also be remembered that a single-function boiler with a tank not only takes up more space than its dual-function counterpart, but also the cost of the boiler and the hot water tank should be taken into account in the calculation. If your customer does not care about immediate access to a large amount of hot water, he should choose the dual-function version.

Condensing boiler in the Onninen offer

The Onninen wholesale offer includes Termet gas boilers. It is a leading manufacturer of heating devices on the Polish market - boilers, heaters and modern solutions based on renewable energy sources. The company has its own design office and research laboratory where new manufacturing technologies and construction documentation for all products are developed. Termet sets standards on the market and constantly ensures the high quality of the products offered. We encourage you to familiarize yourself with the offer of single-function and dual-function condensing boilers from this company, which are available at the Onninen installation wholesaler .

Exchange benefits in the new OnnTop loyalty platform!

Summary

We hope that reading the above article has dispelled any doubts. A condensing gas boiler is an ecological source of heat and a tool for heating domestic water. Thanks to two models of condensing boilers, you can easily adjust the heating installation to the individual needs of the customer.

Do you have questions about the industry? Join the Świat Instalacji group!