Boiler

RM 7800 Control Panel - The standard NEMA 12 control panel contains
on/off pushbuttons or switches, manual flame potentiometer, relays, the
Honeywell RM7800 flame safeguard, and a 4" alarm horn with silencing switch.
No Propietary Trim - The majority of Johnston Boiler controls are "off the
shelf" items which eliminates stocking of proprietary parts and lengthy down
time in the event of control malfunctions
The Factory Test - Each costumer ordered packafge is completely fire tested
from low fire to high fire verifying safety control shutdowns, burner
performance and fuel/air ratio to assure product performance as specified.
Custom Engineered/Custom Built - Every Johnston Boiler is specifically
engineered and built to every costumer's needs and specifications. Special
sizes, fuels, and auxiliary equipment are "no problem" with Johnston.
Ease of Fireside Inspection - Front and rear doors are hinged and davited
to provide simple opening and minimum clearance for full access to fireside
tube surfaces, which eliminates the necessity of disconnecting the burner and
fuel piping.
Waterside Inspection - Handholes are furnished in the front and rear heads
so area below surface can be observed for sediment and mud accumulation.
A manhole is located in the rear head (front head on 3 pass) for easy
inspection and waterside access.
Fuel Flow Control Valves - Contoured cam valves provide reliable fuel to air
ratio set points from low fire to high fire assuring the best burner efficiency.
Fan - Swing-away hinge mounted fan assembly permits easy access to
centrifugal fan and burner internals without having to disconnect fuel lines,
burner or entire boiler front (100-1600HP)
RM 7800 Control Panel - Each boiler is equipped with a top mounted
continuous surface blowoff tapping with integral diptube for connection to a
surface metering valve to maintain proper TDS water quality.
Steam Baffle - Th On all steam boilers, an integral baffle is located below the
nozzle outlet and assures dry steam for process load applications.
Insulation & Jacket - TA minimum of 2 inches of fiberglass blanket is used
on the entire pressure vessel shell and rear head. This insulation is covered
with a galvannealed non-corroding steel jacket. Segments are attached with a
locking seam joint and self-tapping screws
Minimal Use of Refractory - Johnston uses a durable, lightweight ceramic
fiber blanket in all front and rear flue doors. This saves on expensive
refractory door repair.
Copyright Steam & Combustion Technology Inc.
Designed by V.C.P. Productions
 
BOILERS
Products Features
 

15 Year Warranties

Low Maintenance Costs

Low NOx Emissions as low as 9, 12 or 30 PPM

Efficiencies up to 90%

3 & 4 Pass Water-Back Firetube Design

50-2500 BHP (1,700 - 85,000 PPH)

Each boiler is fully factory fire tested over the complete operating range. The
boilers are built in accordance with the latest ASME code requirements,
National Electric Code and other required local, state and insurance
requirements. Dependent on the design and operating conditions, efficiencies
can reach up to 90%.  Call or contact us for more information.
Press here for Johnston literature
Continuous operation since 1864.

Both 3 and 4 pass models include a 15 year limited pressure vessel and front
and rear flue door warranty.  

The Johnston 3-pass boiler has large steam and water storage areas, high
efficiencies and the ability to meet wide load demands. The three pass design
can be manufactured up to a 2500 HP steam boiler. As well as the 4-pass
design, the 3-pass maximizes heat transfer while minimizing the use of
refractory - no expensive door repairs.

The four pass design was first built in 1978 so that customers could have
water back design reliability with the four pass design efficiency. Every
Johnston 4-pass maximizes effective heat transfer using a full five square
feet of heating surface per BHP. Also, the rear tube sheet has only one inside
and one outside surface temperature, which reduces stress and keeps
maintenance to a minimum. As the combustion chamber is part of the
pressure vessel, internal water circulation is improved and overall boiler
efficiency is enhanced.

Johnston Boiler Company is know for quality, dependability and efficiency.
Johnston manufacturers the highest quality packaged boilers on the market.
Their boilers are used for process as well as commercial applications. With
Johnston, we can reduce your operating costs. We have the highest
efficiencies and best warranties in the industry. Our main products consist of
water-back, firetube, 3- or 4-pass, steam or hot water boilers.