Water temperatures

The heat carrier can be heated to different temperatures. In normal boilers, temperatures do not usually exceed 90 °C, remaining below the boiling point of water at atmospheric pressure. In larger boilers, to serve neighborhoods, it reaches up to 140 °C, maintaining high pressure in the pipes so that it does not evaporate (superheated water). There are also steam boilers, in which the water is evaporated and the steam is distributed to the terminal elements, but in Europe they are largely out of use, because the surface temperature of these turns out to be very high and entails the danger of burns. There are also boilers in which the water is heated to temperatures below 70 °C and which achieve high efficiency (condensing boiler).

Energy and deposits

The energy used can come from solid fuels (firewood, coal, wood pellets), liquids (fuel oil, diesel) or gases (liquefied petroleum gases or LPG, natural gas) or it can be electrical energy (including renewable electricity) or thermal energy (such as that from solar panels, geothermal or aerothermal energy.

With respect to gas, for the packaging (bottles) of butane each weighs 13 kg, and the propane bottles weigh 11 kg each, although there are 35 kg bottles, of which several can be put in a battery. Propane can be supplied in larger quantities in tanks (also called bulk) or if it is piped (propanated air).

Combined boiler

A combination boiler is one used for heating and domestic hot water.

A boiler's efficiency is the relationship, generally expressed as a percentage, between the heat actually produced (useful heat) in the boiler and the heat production capacity of the fuel used.[1]​.

Two types of yield are normally considered: instantaneous yield") and seasonal yield").

There are several processes that reduce performance during combustion:

Instantaneous performance is measured with the boiler running, at full power and when it has been running for a while. It takes into account the first three causes of losses among those listed above. The boiler performance requirements demanded by the various national and international regulations refer to this performance specifically.

The fourth cause, the latent heat of vaporization of the water formed in combustion, is taken directly into account when taking the efficiency over the lower calorific value, so, although it is a heat loss, it is not accounted for in most cases.

Between one thing and another, the instantaneous efficiency of a boiler ranges between 70% and just over 90%, based on the lower calorific value of the fuel, with large boilers having better performance; It also improves performance by partializing heat generation, with two or more generators in parallel or with three-stage or modulating burners, so that some boiler does not stop at any time.

The aforementioned condensing boilers can have efficiencies of 105 percent on the lower heating value, but obviously always below 100 percent when referring to the higher heating value.

"Seasonal performance") also takes into account the last cause and depends, more than on the generator itself, on the use made of it and the way it is installed (in series with others, with a single or multi-stage or modulating burner, etc.).

Another essential condition for the good performance of the generators is to carry out adequate maintenance, not only cleaning, but also tuning up the burner. During operation they lose the good point, and then performance is reduced (excess air or lack thereof, with part of the fuel unburned).

The UNI 10389":2009 standard contemplates the following types of performance:.

They must also have accessories such as:.

The most common accessories are the following:

Water temperatures

The heat carrier can be heated to different temperatures. In normal boilers, temperatures do not usually exceed 90 °C, remaining below the boiling point of water at atmospheric pressure. In larger boilers, to serve neighborhoods, it reaches up to 140 °C, maintaining high pressure in the pipes so that it does not evaporate (superheated water). There are also steam boilers, in which the water is evaporated and the steam is distributed to the terminal elements, but in Europe they are largely out of use, because the surface temperature of these turns out to be very high and entails the danger of burns. There are also boilers in which the water is heated to temperatures below 70 °C and which achieve high efficiency (condensing boiler).

Energy and deposits

The energy used can come from solid fuels (firewood, coal, wood pellets), liquids (fuel oil, diesel) or gases (liquefied petroleum gases or LPG, natural gas) or it can be electrical energy (including renewable electricity) or thermal energy (such as that from solar panels, geothermal or aerothermal energy.

With respect to gas, for the packaging (bottles) of butane each weighs 13 kg, and the propane bottles weigh 11 kg each, although there are 35 kg bottles, of which several can be put in a battery. Propane can be supplied in larger quantities in tanks (also called bulk) or if it is piped (propanated air).

Combined boiler

A combination boiler is one used for heating and domestic hot water.

A boiler's efficiency is the relationship, generally expressed as a percentage, between the heat actually produced (useful heat) in the boiler and the heat production capacity of the fuel used.[1]​.

Two types of yield are normally considered: instantaneous yield") and seasonal yield").

There are several processes that reduce performance during combustion:

Instantaneous performance is measured with the boiler running, at full power and when it has been running for a while. It takes into account the first three causes of losses among those listed above. The boiler performance requirements demanded by the various national and international regulations refer to this performance specifically.

The fourth cause, the latent heat of vaporization of the water formed in combustion, is taken directly into account when taking the efficiency over the lower calorific value, so, although it is a heat loss, it is not accounted for in most cases.

Between one thing and another, the instantaneous efficiency of a boiler ranges between 70% and just over 90%, based on the lower calorific value of the fuel, with large boilers having better performance; It also improves performance by partializing heat generation, with two or more generators in parallel or with three-stage or modulating burners, so that some boiler does not stop at any time.

The aforementioned condensing boilers can have efficiencies of 105 percent on the lower heating value, but obviously always below 100 percent when referring to the higher heating value.

"Seasonal performance") also takes into account the last cause and depends, more than on the generator itself, on the use made of it and the way it is installed (in series with others, with a single or multi-stage or modulating burner, etc.).

Another essential condition for the good performance of the generators is to carry out adequate maintenance, not only cleaning, but also tuning up the burner. During operation they lose the good point, and then performance is reduced (excess air or lack thereof, with part of the fuel unburned).

The UNI 10389":2009 standard contemplates the following types of performance:.

They must also have accessories such as:.

The most common accessories are the following: