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Comparison Viessmann Vitodens 100-W B1HC300 35 kW 35 kW vs Viessmann Vitodens 100-W B1HC042 35kW 35 kW

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Viessmann Vitodens 100-W B1HC300 35 kW 35 kW
Viessmann Vitodens 100-W B1HC042 35kW 35 kW
Viessmann Vitodens 100-W B1HC300 35 kW 35 kWViessmann Vitodens 100-W B1HC042 35kW 35 kW
from $1,347.84 up to $1,695.92
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from $1,438.77
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Energy sourcegasgas
Installationwallwall
Typesingle-circuit (heating only)single-circuit (heating only)
Heating area280 m²280 m²
Condensing
Technical specs
Heat output35 kW35 kW
Power supply230 V230 V
Power consumption119 W148 W
Coolant min. T40 °С40 °С
Coolant max. T80 °С80 °С
Heating circuit max. pressure3 bar3 bar
Consumer specs
"Summer" mode
Heated floor mode
Circulation pump
Control busOpenThermOpenTherm
Boiler specs
Efficiency109 %108 %
Combustion chamberclosed (turbocharged)closed (turbocharged)
Flue diameter60/100 mm60/100 mm
Inlet gas pressure13 mbar13 mbar
Max. gas consumption2.5 m³/h3.5 m³/h
Expansion vessel capacity8 L
Connections
Gas supply1/2"
Central heating flow3/4"
Central heating return3/4"
Safety
Safety systems
gas pressure drop
water overheating
flame loss
draft control
water circulation failure
frost protection
gas pressure drop
water overheating
flame loss
draft control
water circulation failure
frost protection
More specs
Dimensions (HxWxD)700x400x350 mm700x400x350 mm
Weight39 kg37 kg
Added to E-Catalognovember 2016june 2016

Power consumption

The maximum electrical power consumed by the boiler during operation. For non-electric models (see Energy source), this power is usually low, as it is required mainly for control circuits and it can be ignored. Regarding electric boilers, it is worth noting that the power consumption in them is most often somewhat higher than the useful one since part of the energy is inevitably dissipated and not used for heating. Accordingly, the ratio of useful and consumed power can be used to evaluate the efficiency of such a boiler.

Efficiency

The efficiency of the boiler.

For electric models (see "Energy source"), this parameter is calculated as the ratio of net power to consumed; in such models, indicators of 98 – 99% are not uncommon. For other boilers, the efficiency is the ratio of the amount of heat directly transferred to the water to the total heat amount released during combustion. In such devices, the efficiency is lower than in electric ones; for them, a parameter of more than 90% is considered good. An exception is gas condensing boilers (see the relevant paragraph), where the efficiency can even be higher than 100%. There is no violation of the laws of physics here. It is a kind of advertising trick: when calculating the efficiency, an inaccurate method is used that does not take into account the energy spent on the formation of water vapour. Nevertheless, formally everything is correct: the boiler gives out more thermal energy to the water than is released during the combustion of fuel since condensation energy is added to the combustion energy.

Max. gas consumption

Maximum gas consumption in the boiler with the corresponding energy source (see above). Achieved when the gas heater is operating at full capacity; with reduced power and consumption, respectively, will be lower.

Note that boilers of the same power may differ in gas consumption due to the difference in efficiency. While the more fuel-efficient models tend to cost more, the price difference pays off in gas savings.

Expansion vessel capacity

The capacity of the expansion tank supplied with the boiler.

The expansion tank is designed to drain excess water from the heating system when the total volume of liquid increases as a result of heating. It consists of two parts connected by a flexible membrane: in one, hermetically closed, there is air under pressure; in the other, excess water enters, compressing the membrane. In this way, a catastrophic increase in pressure in the heating circuit is avoided. The optimal volume of the expansion tank depends on several system parameters, primarily the volume and composition of the coolant; detailed recommendations for calculations can be found in special sources.

Gas supply

The diameter of the pipe for connecting the gas supply pipe in the boiler with the corresponding type of power supply (see "Energy source").

Diameters are indicated in inches. In some cases, it is allowed to connect a pipe of a different diameter through an adapter, but the best option is still a match in size. The most common options are 1/2" and 3/4".

Central heating flow

The diameter of the pipe for connecting the pipe through which the heated water enters the heating system from the boiler.

Diameters are indicated in inches. In some cases, it is allowed to connect a pipe of a different diameter through an adapter, but the best option is still a match in size. Among which models stand out for 3/4", 1", 1 1/4" and 1 1/2".

Central heating return

The diameter of the pipe for connecting the pipe through which the cooled water returns from the heating system to the boiler.

Diameters are indicated in inches. In some cases, it is allowed to connect a pipe of a different diameter through an adapter, but the best option is still a match in size.
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