Brochure

44
Variable Fire (VF
™
) High
Efficiency Circulating
Water Heaters
Up to 87% Thermal Efficiency
The Art of Flexibility
The VF
™
Circulating Water Heater delivers an exceptionally high thermal efficiency
by combining an advanced modulating venturi-mixing gas/air ratio system with a
vertical multi-pass copper heat exchanger for outstanding efficiency of up to 87%
and low NOx emissions that meet the most stringent standards.
The VF
™
Water Heater is capable of firing from 100% to 25% or a 4:1 turn-down
ratio of rated input based on the current system demand. The VF’s modulating
capability is virtually limitless, and the boiler’s output is based strictly on the current
system demand and the required BTU's needed to maintain the desired system set
point temperature.
Category IV Listed
Professional Start-Up Service
Furnished
Thermal Efficiency
n Meets the thermal efficiency and
standby loss requirements of the U.S.
Department of Energy and current
edition of ASHRAE/IESNA 90.1
Low NOx Operation
n Complies with SCAQMD Rule 1146.2
and other Air Quality Management
districts with similar requirements for
low NOx emissions
Other VF
™
Features:
n ASME Pressure Relief
Valve 125#
n Contacts for 0-10 VDC BMS
External Control
n Contacts for Alarm or
Any Failure
n Factory-Mounted Flow Switch
n Low Gas Pressure Switch
n All Bronze Factory Sized Pump
Included (Shipped Loose)
n Digital Inlet/Outlet Temperature
Read Out
n Manual Reset Hi-Limit
VF
™
Options:
n Sequence Panel – Can manage 1 to 4
modulating units (Includes remote
Tank sensor and sensor well)
n Alarm Bell
n Low Water Cutoff w/Manual
Reset and Test
n LP Gas
n Vent Kits:
- Horizontal Exhaust Cap
- Horizontal Air Intake Cap
- Horizontal Direct Vent Kit
- Category IV to Category II
Conversion Kit
Warranty:
n 5-Year Limited Heat Exchanger
Warranty
™
MODEL
NUMBER
BTU/HR
NATURAL GAS
INPUT
BTU/HR
NATURAL GAS
OUTPUT
RECOVERY
100°F RISE GPH
VENT SIZE
(INCHES)
AIR
INTAKE
SIZE
LOAD
FACTOR
APPROX.
SHIPPING
WEIGHT
(LBS)
VWH-500N 500,000 425,000 573 4" 5" 2.78 573
VWH-750N 750,000 637,500 622 5" 5" 2.78 622
VWH-1000N 999,999 849,999 671 6" 6" 2.78 671
VWH-1500N 1,500,000 1,275,000 1,117 6" 6" 2.78 1,117
VWH-2000N 2,000,000 1,700,000 1,186 8" 8" 2.78 1,186
®
Hot Water Applications:
With 5 models to choose from
and BTU inputs from 500,000
BTUHs to 2 million BTUH there
is a VF Water Heater or a
combination of VF’s that is
ideal for almost any large
water heating application.
AOSCA80000 R July 2014 Commercial Catalog_108078_ResidentialFul#7A635.qxd 7/16/14 4:29 PM Page 44