LAARS MAX 165 (DV) - Installation, Operation and Maintenance Instructions - Manual (Page 3)

MAX Oil-Fired Boiler Page 3
SECTION 1.
General Information
1A. Introduction
The MAX Boiler has been constructed to meet
the stringent requirements of the ASME Boiler Codes
and designed to provide a rapid response to hot water
and heating demands at a very high thermal efficiency.
This is a low mass boiler. To take advantage of
this feature, and prevent short cycling, always select
the lowest firing rate satisfactory for the load
requirement.
The boiler is supplied either for connection to a
conventional chimney or comes complete with a
balanced flue system for direct venting through the
wall.
With the balanced flue system, air for
combustion is drawn from outside through a terminal
and ducted directly to the burner, making the boiler
virtually room sealed. Flue gases are discharged
through the same terminal so that wind pressures are
applied equally to inlet and outlet, making it a true
balanced flue system. A silencer is also incorporated
in the terminal to reduce the flue gas discharge noise.
This is a particularly useful feature if the terminal is
located near a bedroom window or adjacent to
neighboring properties.
The boiler is constructed with two concentric
water jackets, the inner one forming the furnace tube
and the outer the flue gas annulus. Flue gas retarders
fitted around the annulus are specifically designed to
extract the maximum heat from the gases with
minimum pressure loss.
The simple annular design also makes it possible
to keep the water content to a minimum (only 3.2 gals.
[12L] for the MAX (DV) 75, 100, 120 and 5.1 gals.
[19L] for the MAX (DV) 140, 165). Because of this
low mass, water is rapidly heated to the temperature
demands. Another benefit of the low thermal mass is
the insignificant level of standby loss when the burner
shuts down.
To achieve the best possible heat transfer, the
boiler is designed on the “Series Flow” principle
whereby the return water is preheated by first passing
through the outer water annulus before coming into
contact with the furnace tube. This arrangement also
provides a counter flow of flue gases and water so that
the coolest gases come into contact with the coolest
water for the most efficient heat transfer.
Heavily insulated doors at front and back of
boiler, provide easy access for cleaning and
inspection, with the burner being swung on the front
door either left or right as required.
Accurate sensing of temperature and pressure is
assured by grouping all controls and safety devices on
a common supply manifold.
The use of the latest flame retention head burner
allows the boiler to operate under a slight positive
pressure which ensures stable combustion under
virtually all operating conditions.
MAX (DV) GPH Nozzle Pump Input AFUE Heating Water Shipping
Model Rate Size Pressure MBTH/hr Rating Capacity Content Weight
GPH P.S.I. % BTU/h gal. L lbs. kg
75 0.72 0.65 140 101 87.0 85,900 3.0 12 324 147
100 1.00 0.85 140 140 86.5 121,200 3.2 12 324 147
120 1.20 1.00 140 168 86.0 141,600 3.2 12 324 147
140 1.40 1.20 150 196 85.6 166,000 5.1 19 431 196
165 1.65 1.35 150 231 85.0 192,400 5.1 19 431 196
Table 1. Boiler Specifications.