The Reznor’s Model DFC Direct-Fired, Vertical/Horizontal, Indoor/Outdoor, Packaged, Makeeup Air Heating and Air Conditioning System
The Reznor Model DFC Series units are direct-fired/makeup and space heaters designed for either indoor or outdoor installation. Model DFCH is horizontally arranged. Model DFCV is a vertical cabinet. Units can be configured for floor mount, outdoor pad mount, rooftop or suspended installation. Model DFC systems are available to operate on either natural gas or propane.
Maximum heating capacity is 12,830 MBH. Maximum air handling capacity is 90,000 CFM. The DFC Series provides discharge air at a maximum temperature rise of 120°F.
The gas manifold has stainless steel mixing plates and offers a 30:1 turndown ratio. There is also a solid state flame monitoring system and a burner observation port.
The AMCA-rated forward curved DWDI centrifugal blower (Class I or Class II) has a polished steel shaft with rust inhibitor. Backward inclined and air foil fans are also available. Heavy duty industrial bearings are standard. Adjustable V-belt drives are used on motors through 5 HP. Fixed drives are used on motors 7.5 HP and larger. Several options are available for internal and external vibration isolation including 1” or 2” deflection spring hangers and rubber-in-shear isolation.
The cabinet is constructed of 18, 16 or 14 gauge Galvaneal steel casing with rust-resistant gray enamel paint finish on a welded structural or formed channel base frame. The 1” or 2” thick, high density insulation is glued and pinned to the inside cabinet walls. Cabinets can be single wall, solid double wall (for cleaning) or with a perforated inner wall liner (for sound attenuation). Outdoor units larger than 218 have a sloped roof. Service platform is available for easy access to controls and gas train.
Vertical units can be mounted on the floor, suspended or mounted on a 3’ or 5’ stand. Service platforms are also available for vertical or horizontal units for a convenient place to stand when working in the controls section. Service platform available for filter cabinet access for horizontal units.
Model DFCH (horizontal configuration) can be arranged for vertical up, vertical down or horizontal supply air discharge. Model DFCV (vertical configuration) can also be arranged for vertical up, vertical down or horizontal supply air discharge.
Standard configuration is for 100% outside air. An optional return air plenum (return air bypasses burner) is available for recirculating up to 80% return air (available in U.S. only). Inlet air weather hoods have an expanded metal screen with 2” filters available. Motorized two-position inlet and discharge dampers have a two-position spring return and end switch.
Modules available for filter cabinets, evaporative cooling, return air plenum, DX or chilled water cooling coils; as well as steam, hot water or glycol heating coils.
Electrical controls include electronic flame safeguard relay manual reset; high and low airflow pressure switches; motor starter with overload protection; control panel service switch; and terminal connections for exhaust interlock.
The discharge air temperature control can be used with or without a room override connected to room thermostat. Space temperature control can also be selected. Other temperature control options include night setback, freeze protection and inlet air control which shuts down the burner when outside air exceeds temperature setting. Standard features include flame rod ignition system with optional dual flame rods and UV flame supervision.
NEMA4 control panel available unit mounted or remote enclosure. Explosion resistant panels also available.
Units provided with ETL (for installation in the United States) or ETLC (for installation in Canada) rating plate.
Manifolds are available to meet ANSI, FM (Factory Mutual), IRI or FM/IRI standards.
All units are factory wired, piped and test fired.
STANDARD FEATURES:
● ETL (United States) or ETLC (Canada) rating plate
● Class I Blower (Sizes 127 – 218); Class II Blower (Sizes 222 – 236)
● Natural gas or propane operation
● 208/3/60 Supply voltage
● Cabinet
– Welded structural or formed channel base frame
– Hinged access doors
– Conveniently located lifting lugs
– Heavy steel casing (18 gauge) with rust resistant gray enamel finish
– One-inch thick, 1.5 lb. density, neoprene-coated fiberglass insulation pinned and glued to inside cabinet walls
– Sloped roof on outdoor units on sizes 218 and larger
● Flame rod ignition system
● Left hand or right hand side controls
● 100% outside makeup air with constant supply volume
● Blower/Motor
– AMCA-rated forward curve DWDI centrifugal blower
– Polished steel shaft with rust inhibitor
– Maximum allowable operating speed set to 75% of first critical speed
– ODP motor, 1800 RPM, T frame, 1.15 service factor mounted on adjustable base
– Drives designed for 150% of motor brake horsepower
– Adjustable V-belt drives on 5 hp motors
– Fixed drives on motors 7.5 hp and larger
OPTIONAL FEATURES – FACTORY INSTALLED:
● Class II Blower
● Gas manifold to meet ANSI, FM, IRI or FM/IRI Standards
● Manifold arrangements from 700 to 12,830 MBH
● Gas pressure gauge on manifold
● 230/3/60, 460/3/60 or 575/3/60 Supply voltage
● Ignition system
– Dual flame rod
– UV flame supervision
● Remote reset button for flame safeguard system
● Gas pressure safety switch
– High gas pressure safety switch (manual reset)
– Low gas pressure safety switch (manual reset)
– Single body high and low gas pressure safety switch (manual reset)
● Proof of closure valve
● High gas pressure regulator
● Purge relays
– Post purge timer and relay
– Pre-purge timer and relay
● Cabinet
– Gray enamel finish on 16 or 14 gauge Galvaneal
– 1” thick high density (2 lb.) or 2” thick insulation
– Internal liners – 22 gauge solid lining (for cleaning) or perforated lining (for sound attenuation)
– Control panel weather housing for outdoor applications
– Horizontal or vertical discharge air options
– Special coatings
● Three foot or five foot tall mounting stand
● Service platform for controls section (horizontal or vertical units) and filter cabinet (horizontal only) access
● Vibration isolation
– 1” or 2” deflection spring vibration internal isolation
– 1” or 2” dflection external spring hangers
– Motor/blower rubber-in-shear isolation
– External spring isolation under unit channel base
– Seismic vibration isolation
● Supply air discharge
– Horizontal, vertical up or vertical down configuration (all models)
– Two position motorized discharge air shutoff dampers with spring return
– Low leak airfoil dampers with two position motor and spring return
● Return air plenum capable of recirculating up to 80% return air (return air bypasses burner) – not available in Canada
● Motorized Inlet and discharge dampers
● Motors
– TEFC
– Premium efficiency ODP
– EPACT-compliant ODP
● Wide variety of control options
OPTIONAL FEATURES – FIELD INSTALLED:
● Extended lube lines
● Filter cabinet
– V-bank filter section
– Side access
– 2” permanent or pleated filter
– Access doors completely sealed with gaskets
● Evaporative cooling module
– with 12” Celdek® media
– with 12” Glasdek® media
– with 2” aluminum mesh washable prefilters
– Automatic fill and drain kit
– Outside air thermostat for fill and drain
● Discharge air options
– Three faced trapezoidal cowl with discharge louvers
– Cowl with double deflection louvers
– 4 sided 360 degree louvered discharge plenum (DFCH bottom discharge only)
● 16” or 26” roof curb (DFCH only)
● Wide variety of Temperature controls
● Coil Cabinets
– Cabinets for DX or chilled water cooling
– Cabinets for steam, hot water or glycol heating
● Louvered inlet for maximum velocity of 500 fpm to minimize potential precipitation entering unit