Dovre ASTRO4GA - P, Installation Instructions & Operating Manual

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Appendix 5: Calculation sheet for checking
projected route
Follow the three steps below to check whether the desired route for the concentric chimney exhaust is permitted.
1. Sketch the desired route and use it as a basis for filling in the information required in the table below. You can
disregard the actual roof or wall sleeve here.
Description Abbreviation
Measured
value
Number of metres, vertical (1) … metre
Number of metres, horizontal (2) … metre
Number of metres at an angle of 45° (3) … metre
Number of elbows up to 45°: … x 0.5 metres per elbow (4) … metre
Number of elbows up to 90°: … x 1.0 metres per elbow (5) … metre
2. Use the data above to calculate the values in the following table:
Description Abbreviation Result
Total resistance length = (1)+(2)+(3)+(4)+(5) L … metre
Total vertical length = (1) V … metre
Total horizontal length = (2)+(4)+(5) H … metre
Total vertical length minus Total horizontal length = V - H R … metre
3. Use the table below to determine whether the desired route is permitted and what the position of the restric-
tion plate should be for the appliance to function optimally. Only the natural gas version of the appliance has a
restriction plate. No restriction is permitted on the propane and butane versions.
Top con-
nection
Back connection Assessment of route
Restriction plate pos-
ition (only for natural
gas version)
L > 12 L > 12 route not permitted -
V < 1 V < 1 route not permitted -
(2) => 3 (2) => 3 route not permitted -
R < 0 R < -1 route not permitted -
0 =< R < 2 -1 =< R < 1 route permitted Position 1
26
Subject to change because of technical improvements