eta PE-K 35, Руководство по установке

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49 PE-K installation 35 to 90 kW
2012-02
Pellet store Calculating supply and store size
Calculating supply and store size
Calculating the pellet supply
Rule of thumb for determining the pellet supply in
tons : divide the heating load of the building by 3 .
For the
pellet supply in cubic metres (m³)
,
divide
the heating load by 2 .
Example for a single-family house with average
insulation and
12 kW heating load:
12 kW / 3 =
4 tons
of pellets per year
12 kW / 2 = 6 m³ of pellets per year
Calculating pellet supply from
current fuel consumption
Using the current fuel consumption, you can
roughly estimate the annual pellet supply with the
conversion factors below.
Example for a single-family house with average
insulation and 12 kW heating load:
1,960 l heating oil x 2.04 = 4,000 kg of pellets
2,060 m³ natural gas x
1.94
= 4,000 kg of pellets
2,960 l LPG x 1.35 = 4,000 kg of pellets
1,560 kg LPG x
2.56
= 4,000 kg of pellets
2,660 kg coke x 1.50 = 4,000 kg of pellets
Ground source heat pump with COP 3.4
5,700 kWh of electricity
x
0.70 = 4,000 kg of pellets
Ground source heat pump with COP 2.1
9,500 kWh of electricity
x
0.42 = 4,000 kg of pellets
Heating value and density of pellets
Heating value of pellets = 4.9 kWh/kg
Density of pellets = 650 kg/m³
2 kg pellets = 1 l of extra-light heating oil
Required pellet store size
The required store size is based on the heating load.
Use the rule of thumb "heat load divided by 2" to
fi nd the minimum required store volume. For a
building with 12 kW heating load:
12 kW / 2 =
6 m³ minimum store volume
To be prepared for colder winters, the store should
hold around 20% more than a year's supply .
For this example, that means a
store volume
of 7.2 m³ is needed. Using this volume, we can
determine the necessary room dimensions and the
length of the discharge screw.
Determining the length of the discharge screw /
pellet store
Using the table "Useful cross section of a pellet
store" on the previous page, we can determine
the length of the discharge screw for the amount of
pellets to be stored. That length also determines the
minimum length of the pellet store.
Example: Room width 2 m and height 2.4 m:
The table yields a usable cross section of 2.9 m².
The volume of pellets to be stored in the example
above is 7.2 m³:
=> 7.2 m³ / 2.9 m² = 2.5 m length
A discharge screw of 2.5 m length is needed.
Example: Room width 2.8 m and height 2.4 m:
The useful cross section of 3.59 m² yields a room
length or discharge screw length of:
=> 7.2 m³ / 3.59 m² =
2.0 m length
The screw should preferably be oriented along
the long axis
of the room. The narrower the room,
the less space is lost under the 40° tilted fl oor. The
unobstructed
room length of the pellet store
should be
at least 100 mm longer
than that of the
discharge screw.
The discharge screw can be as much as 0.6 m shorter
than the room without any problems. If the store is
also faced with tilted panels at the end, the screw
can even be up to 1.5 m shorter.