MVB® Modulating Vertical Water Heaters 503A-2003A

Time-honored technologies unite with cutting-edge advancements in Raypak’s MVB modulating vertical water heater.  Small space is no longer a problem, and our compact design fits through a 32” door opening to make it the perfect choice for those hard-to-reach retrofit projects.  The MVB is built to last, from the structural steel base to the stainless steel flue wrapper.  The built-in VERSA IC® Integrated Control platform precisely tracks the heating load to eliminate costly overshooting, and the 7:1 turndown ensures high efficiency throughout the firing rate and actually increases efficiency during part load, right when you want it.

    Model Number Full Input in
     Flue Dia.
    WH7-503A 500,000  6"
    WH7-753A 750,000  6"
    WH7-1003A 999,000  6"
    WH7-1253A 1,250,000  8"
    WH7-1503A 1,500,000  8"
    WH7-1753A 1,750,000  8"
    WH7-2003A 1,999,000  8"

    • 87% Thermal Efficiency at Full Rate.
    • Positive vent pressure, Condensing Appliance.  Cat IV Vent Required.
    • Bronze headers with copper finned tube heat exchanger standard. Cupro-Nickel tubes available as options. ASME Section IV constructed and stamped, National Board registered.
    • CSA Low-Lead certified, less than 0.25% Lead.
    • Certified to ANSI Z21.10.3.
    • Minimum Inlet Water Temperature: 120°F.
    • Maximum Setpoint: 150°F.
    • Electronic Modulation, up to 7:1 Turndown.
    • VERSA IC® Control Package with LCD Display.
    • Status Display Lights.
    • Cascade control of up to 4 units, no external sequencer required.
    • Diagnostics Center with History, English, no codes.
    • Modbus RTU BMS port (RS485).
    • 0-10 VDC BMS Interface (Setpoint or Direct Drive).
    • All models indoor/outdoor construction.
    • Certified under SCAQMD Rule 1146.2.  Meets all Low NOx regulations.
    • Engineered with precisely matched system components.
    • Smallest installed footprint (5.4 square feet) design fits tight spaces and easily replaces larger boilers.
    • 100% Factory Fire Tested.
    • Complete cabinet protects all controls and wiring. Tough, rust-resistant powder-coat finish.
    • Suitable for altitudes up to 10,000 ft. (derate above 2,000 ft.).
    • No boiler condensate drain required (proprietary design)
    • Available for natural gas or propane.
    • Integral Combustion Air Filter (MERV8).
    • Multiple Pump Outputs – Boiler Pump, System Pump.
    • Whisper-Quiet Operation.
    • Proudly Assembled in the USA.



    • BACNet IP, BACnet MS/TP, Modbus TCP, N2 Metasys (B-85)
    • Lonworks (B-86)
    • Alarm with 4” Bell (E-5)
    • Low Water Cutoff (F-10)
    • Cold Water Run
    • Condensate Neutralizer (Z-12)