Condensing boilers are
heating devices that thanks to high efficiency allow you to reduce home heating
costs. Their advantage over
non-condensing boilers is very large.
Condensing boilers are
heating devices that thanks to high efficiency allow you to reduce home heating
costs. Their advantage over
non-condensing boilers is very large.
Non-condensing boilers
(conventional) do not use part of the energy contained in the fuel - so-called
latent heat. In order to release
it, it is necessary to condense (condense) the water vapor present in the
exhaust. This happens as a result
of cooling them to a temperature lower than the so-called dew point, that is
about 56oC for natural gas, 52oC for liquid gas and 47oC for heating oil. This is possible with condensing
boilers - equipped with heat exchangers designed to allow condensation to occur
in them.
High efficiency of
condensing boilers
Characteristic for
condensing boilers is their efficiency - greater than 100%, which at first
glance contradicts common sense.This is because it was assumed to determine the
efficiency of heating boilers in relation to the calorific value of fuel - the
amount of heat contained in dry exhaust gas, without taking into account the
water vapor content. However, the
total amount of heat, ie the so-called heat of combustion, is higher by the
value of latent heat. How much it
is depends on the water content in the exhaust, which is different for
different fuels. In the case of
natural gas, the heat of combustion is higher than the heating value by 11%,
for propane by 9%, and in the case of heating oil by 6%. Hence, the theoretically achievable
maximum efficiency of a condensing boiler (related to the heating value - in
accordance with the standards adopted in Europe)
is 111%, 109% and 106% respectively.
The condensing boiler
pays off
Higher efficiency of
condensing boilers causes that they consume by several percent less fuel than
their conventional counterparts. Unfortunately,
the construction of condensing boilers is a bit more complicated, and therefore
for a boiler for a single-family house you have to pay a few thousand zlotys
more than for non-condensing. Nevertheless,
rising fuel prices mean that a dozen percent savings in home heating expenses
are able to compensate for this higher price. Thus,
the purchase of a condensing boiler, especially for natural gas, can be
considered profitable.
