Products:  Fired:  MC Series

Model MC  Watertube Boiler
Specification

Note:  items shown in parenthesis () are options.

1. General

Furnish and install as shown on the plans ____ one (1) Precision model MC___-____-____ forced draft, (natural gas) (propane) (oil) (gas/oil) fired watertube (steam) (water) boiler rated at _____ boiler horsepower. Boiler shall be designed for a maximum allowable working pressure of ____psi and shall operate at _____psi.  Boiler shall be completely factory assembled and tested, with controls and trim as specified below.  Complete package shall be UL Listed and shall carry the Underwriters Laboratories Listing Mark.  Units rated at 9.5 boiler horsepower and over shall also comply with ASME CSD-1.  Boiler shall be designated for _____V, _______PH, _______HZ electrical supply with single power connection.

2. Pressure Vessel

Vessel shall be constructed and stamped in accordance with ASME Section IV (hot water or 15 psi steam) or Section I (150 psi) and shall be registered with the National Board.  Shell and tubesheets shall be fabricated from carbon steel.  Tubes shall be 1-1/2” OD x 0.105 wall spec SA178A ERW.  Vessel shall be stress relieved (units > 15psi design) and equipped with inspection openings as required by the applicable ASME Code.

3. Combustion Chamber

Combustion chamber shall be tangent water wall on bottom, top and one side with rigidized ceramic fiber blanket on the remaining side.  Combustion chamber rear wall shall be of high temperature refractory, not less than 4” thick. 

4. Burner

Provide forced-draft, flame retention head burner to burn (natural gas) (oil) (gas/oil) (propane) with (on-off) (low-high-low) (full modulation) firing rate control.  Burner shall be equipped to fire at a maximum input of _____Btu/hr at an elevation of _____ ft.  Blower motor shall be 3450 rpm design with motor starter (units over ¾ hp).  Burner controls shall conform to UL795, CSD-1 (FM) (IRI) requirements.  For electrical supplies other than 120V, the burner shall be equipped with a control circuit transformer.

5. Boiler Controls

Boiler shall be provided with applicable trim and controls as required by ASME:

As a minimum, the following shall be provided:

• Hot Water:  temperature gauge, pressure gauge (with cock), manual vent valve, properly sized safety relief valve(s), drain valve, low water cutoff of (probe) (float) type, temperature limit cutout, operating temperature control.

• Steam:  pressure gauge (with cock), water sight gauge, properly sized safety valve(s), blowdown valves, surface blowoff provision, low water cutoff of (probe) (float) type, level control, pressure limit cutout, operating pressure control.

6.  Packaging

The boiler shall be completely factory assembled and mounted on structural channel support frame.  Lifting lugs are to be an integral part of the support frame to facilitate lifting and rigging.    All specified components will be factory mounted, piped and wired.  Boiler shall be insulated with durable ceramic fiber, mineral wool, and fiberglas insulating materials such that the outside surface temperature will not exceed 130^º F during continuous operation at maximum firing rate.  The boiler is to be housed in a rectangular outer casing of steel and coated with a durable enamel finish.

7.  Quality Control

Complete packaged boiler shall be manufactured by Precision Boilers in strict accordance with ASME Boiler and Pressure Vessel Code in an ISO quality system.

Specifications subject to change without notice.