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12
MorrHeat - Most Heat In The Industry - Rev 3/18/2019
The MorrHeat boilers operates with positive pressure throughout the boiler furnace and
flue passages. The over-fire pressure will vary according to boiler size. Consult local
building codes for proper installation of vent system relative to the fuel being burned.
See burner manufactures draft recomendation.
Boiler breech & stub vent operate at positive
pressure. Entire system must be gas tight .
Stub vent height must be limited to prevent
negative draft. Should negative draft occur
install a barometric draft regulator.
Boiler operates with positive pressure overfire.
Chimney provides negative pressure that is
balanced with a barometric draft control.
Boiler, breech & stub ven operate a positive
pressure: entire system must be gas tight:
Stub vent height must be limited to prevent
negative draft: should negative draft occur,
install a barometric draft regulator.
EACH BOILER MUST HAVE A STUB VENT.
Conventional chimney with multiple boiler
balanced draft.
MULTIPLE BOILERS
BALANCED DRAFT
FORCED DRAFT
MULTIPLE BOILERS
FIG. 3 | CHIMNEY OR VENT SYSTEM
15' TYP
15' TYP
F
F
F
F
F
STACK SUPPORT
QUAD LOCKING
DAMPERING
QUAD LOCKING
DAMPERING
QUAD LOCKING
DAMPERING
QUAD LOCKING
DAMPERING
BAROMETRIC DRAFT
REGULATOR