Spec Sheet
Date: Bid Date:
Project #: Location:
Project Name: Engineer:
Contractor: Prepared By:
Mighty Therm2
Hydronic Boiler
Model MT2H 200-400 Indoor/Outdoor
Specification
Contractor shall supply and install Qty.: Laars Model No. MT2H boiler(s).
The boiler shall be a Laars Mighty Therm2 Model MT2H , rated at the input and output shown on the schedule. The unit(s)
shall be design certified to comply with the current edition of the Harmonized ANSI Z21.13 / CSA 4.9 Standard for Gas-Fired Low Pressure
Steam and Hot Water Boilers, and shall be design certified for both indoor and outdoor use. The unit(s) shall be designed and constructed
in accordance with the ASME Boiler & Pressure Vessel Code, Section IV requirements for 160 psi (1103 kPa) working pressure, and shall
bear the ASME "H" Stamp. The unit(s) shall be constructed to comply with the efficiency requirements of the latest edition of ASHRAE
Standard 90.1.
The water tube heat exchanger shall be a straight tube design with ten 5/8" (16mm) inner diameter integral finned copper tubes, with a
heat exchanger rating of 160 psi (1103 kPa) working pressure. The heat exchanger shall be a low water volume design. All gaskets shall
be non-metallic, outside the jacket, and separated from the combustion chamber to eliminate deterioration from heat. Headers shall have
covers permitting visual inspection and cleaning of all internal surfaces. The heat exchanger shall have a ten year warranty.
The piping side header shall have removable flanges, and the boiler design shall permit removal of the complete heat exchanger for
service from either the front or top, to facilitate maintenance.
The units shall use a proved hot surface ignition with a 15 second pre-purge cycle to clean out the combustion chamber. Upon a call for
heat, if a flame is not detected, the ignition module shall try two more times, and then lockout. If there is a loss of flame signal during a call
for heat, the ignition control shall attempt three re-ignition cycles before locking out. The ignition control shall pre-purge and post-purge the
boiler's blower, and shall have terminals for checking flame signal without having to remove or access ignitor. The control circuit shall be
24V. Unit shall be 120V, single phase, less than 12 Amps.
The boiler shall be standard on/off firing, with an option for two-stage firing. The boiler shall be equipped with a PI temperature
controller with outdoor reset, warm weather shutdown, indirect domestic hot water operation, automatic boiler differential, and codes
for sensor errors. The controller shall have indicator lights for power, heat call, indirect domestic water call, and warm weather
shutdown. The controller shall have pump pre-purge, post-purge, and exercise features. In addition to the temperature control, the
boiler shall be equipped with a non-adjustable manual reset high limit. A terminal strip shall be used for ease of wiring and
troubleshooting. The boiler shall have a control panel cover, such that jacket panels do not have to be removed to access control
components.
Burners shall be multi-port design, and shall be constructed of high temperature stainless steel. The burners shall be designed to mix air
and gas, and burn cleanly with NOx emissions not exceeding 10ppm. Burners shall be in easily-removable burner tray assemblies with no
more than 4 burners per tray.
The combustion chamber shall made of a one-piece, formed, lightweight, ceramic fiberboard insulation to retain heat, and shall be
approved for service temperatures of not less than 2000°F (1093°C). The outer jacket shall be a unitized shell finished with acrylic thermo-
set paint baked at not less than 325°F (163°C). The frame shall be constructed of galvanized steel for strength and protection. Chamber
shall include a sight glass for viewing flame.
Boilers shall have a forced draft design and shall meet a minimum 85% efficiency. The unit shall be designed for vertical venting with
standard B-vent as a fan-assisted Category I appliance, and for horizontal venting as a Category III appliance and shall not require an
external draft hood. The unit shall accept ducted combustion air, or shall be able to pull combustion air from the boiler room. Vent and
ducted combustion air shall each be able to be piped to either the top or the back of the unit, in any combination. Changing from top-to-
back or from back-to-top piping orientation shall be easily accomplished in the field.
The gas train shall have a gas shutoff valve and main gas valve(s) with built-in redundant valve seat(s) and gas regulator(s). Gas valves
shall be flanged, to permit easy removal of each gas valve, gas train and burner tray assembly from the front of the unit.
The boiler shall be provided with an integral, washable combustion air filter. The air filter shall provide 83% arrestence to protect the
burners and blower(s) from debris. The air filter shall be constructed out of open-cell polyurethane foam.
continued >>
Brute Deluxe
Brute Deluxe, BMT2H
Model BMT2H 200-400 Indoor/Outdoor
The boiler shall be a Bradford White Brute Deluxe Model BMT2H_________, rated at the input and output shown on the schedule. The unit(s)