Furnace Flue Gas System - Honeywell Ecomax Series Technical Information

Project planning information for indirect heating

7 .4 Furnace flue gas system

A flue gas system must be fitted on the furnace as a
means of guiding the flue gas to the chimney. In the
flue gas system there should be a low negative pressure
thanks to the draught of the chimney or an exhaust fan.
The branch lines from the furnace flue gas manifold to
the individual burners should be designed such that
condensate cannot seep upstream into the burner.
The branch lines to the burner should stop 10 mm away
from the flue gas connector FLUP, or be fitted flush
with the eductor EJEK.
For indirect heating with flue gas monitoring kit DW and
BCU 465, excessive negative pressure in the flue gas
system or an excessively narrow flue gas pipe diameter
on the furnace can cause problems with setting the
switching point of the pressure switch.
ECOMAX · Edition 10.17
∅1,5Q
∅2Q*
∅2Q*
∅Q
∅Q
* With flue gas monitoring kit DW; without flue gas monitoring
kit DW: 1.5Q to 2Q.
FLUP dia. Q
ECOMAX 0
ECOMAX 1
ECOMAX 2
ECOMAX 3
ECOMAX 4
ECOMAX 5
In a closed flue gas system, a pressure regulator is to
be fitted. The gas and air flow rates depend on the total
pressure differential between the supply lines and the
flue gas system. If the pressure in the flue gas system
fluctuates, the burner capacity changes. In a system
without air/gas ratio control, the lambda may also
change.
∅1,5P
EJEK dia. P
DN 32 43
DN 50 43
DN 50 83
DN 65 98
DN 100 128
DN 100 153
∅P
51