Roberts Gorden CRV-B-4 - Manual (Page 25)

SECTION 6: R ADIANT T UBE AND T AILPIPE
19
Table 5 for the burner model to ensure that the result-
ing tailpipe lengths maintain intended operating char-
acteristic.
6.5.5 Damper Couplings
Damper couplings are needed:
• In any tailpipe branch that carries less flow units
than other tailpipe branches connected to the
same pump
• In unsymmetrical layouts with branches having
the same number of flow units, the damper cou-
pling is placed in every branch except for the
longest branch.
The purpose of the damper coupling is to adjust the
end vent vacuum down to the desired level. These are
to be placed in the tailpipe section and not the radiant
branch. The recommended location is before the first
tee fitting or 10'-40' from the end of the radiant pipe.
See Page 20, Figure 17; Page 23, Figure 21, Page
24, Figure 25, and Page 25, Figure 26 for placement
examples.