Unigas HR91A, Manual Of Installation, Use And Maintenance

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PART II: INSTALLATION
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2.3 Fitting the burner to the boiler
To install the burner into the boiler, proceed as follows:
1
make a hole on the closing door of the combustion chamber as described on paragraph “Overall dimensions”)
2 place the burner to the boiler: lift it up and handle it according to the procedure described on paragraph “Handling the burner”;
3 place the 4 stud bolts (5) on boiler’s door, according to the burner drilling template described on paragraph “Overall dimensions”;
4 fasten the 4 stud bolts;
5 place the gasket on the burner flange;
6 install the burner into the boiler;
7 fix the burner to the stud bolts, by means of the fixing nuts, according to the next picture.
8 After fitting the burner to the boiler, ensure that the gap between the blast tube and the refractory lining is sealed with appropriate
insulating material (ceramic fibre cord or refractory cement).
2.4 Matching the burner to the boiler
The burners described in this manual have been tested with combustion chambers that comply with EN676 regulation and whose
dimensions are described in the diagram . In case the burner must be coupled with boilers with a combustion chamber smaller in dia-
meter or shorter than those described in the diagram, please contact the supplier, to verify that a correct matching is possible, with
respect of the application involved. To correctly match the burner to the boiler verify the type of the blast tube (type 1 or type 2). Verify
the necessary input and the pressure in combustion chamber are included in the burner performance curve; otherwise the choice of the
burner must be revised consulting the burner manufacturer. To choose the blast tube lenght follow the instructions of the boiler manu-
facturer. In absence of these consider the following:
z
Cast-iron boilers, three pass flue boilers (with the first pass in the rear part): the blast tube must protrude no more than Dist = 100
mm into the combustion chamber. (please see the picture below)
z
Pressurised boilers with flame reversal: in this case the blast tube must penetrate Dm 50 ÷ 100 mm into combustion chamber in
respect to the tube bundle plate.(please see the picture below)
The length of the blast tubes does not always allow this requirement to be met, and thus it may be necessary to use a suitably-sized
Keys
1 Burner
2 Fixing nut
3 Washer
4 Sealing gasket
5 Stud bolt
7 Blast tube
Dist
Dm