A.O. Smith VF Series Manuel D’Utilisation

Combustion 
air intake – self
adjusting-no air
shutter required

EMC-5000 
Modulating Control

Advanced pre-mix 
burner design 
precisely mixes 
air and gas prior to
ignition for optimum 
performance, with 
low-NOx emissions 
(meets SCAQMD 
Rule 1146.2)

All non-heating 
surface heat
exchanger compo-
nents are outside
and away from the
combustion and flue
collection areas;
only the copper fin
tubes are exposed
to the products of
combustion

Venturi-mixing gas/air
ratio system works with
variable speed blower to
precisely mix gas and air
throughout firing range,
provides good operation
with supply gas pressures

down to 4˝ WC, and 
is self-adjusting for 
altitudes up to 6,000

feet all while providing 
low NOx emissions that
meet or exceed the most 
stringent standards

Heavy-duty ASME 160 
psi copper finned tube 
heat exchanger—Vertical,
straight tube, multi-pass
design surrounds the
burner with a 360° wall
of copper finned tubing,
making the entire heat
exchanger immune to
thermal shock  

The sealed heat 
exchanger flue collection
system is constructed 
of AL29-4C stainless
steel that is immune 
to corrosive flue gases