Slant/Fin VICTORY II VHS Series User guide

WET-BASE CAST-IRON MODULAR BOILERS
HOT WATER/OIL
APPLICATION GUIDE
INCLUDING
DUAL FUEL
Guidelines for the design, purchase and installation of lant/Fin oil-fired and dual fuel hot water modular boiler systems.
Introduction .............................................................................1
Boiler room design..................................................................5
Boiler room air supply re uirements.......................................5
Venting an oil-fired system ..................................................7,8
Fuel oil storage facilities .........................................................9
Fuel oil delivery systems for single fuel burners ...............9-11
Fuel oil delivery systems for dual fuel burners................11-14
Controls ...........................................................................15,16
CODE AND TANDARD
Oil-fired Caravan installations must comply to local codes or,
in the absence of local codes, to the ANSI/NFPA 31,
Installation of Oil Burning E uipment, latest edition.
In addition, where re uired by the authority having jurisdiction,
the installation must conform to American Society of
Mechanical Engineers Safety Codes for controls and safety
devices for automatically fired boilers, No. CSD-1. The
installation must also conform to the additional re uirements
of Slant/Fin Instruction Book publication no. L-40 latest edition.
All electrical wiring is to be done in accordance with the
National Electrical Code ANSI/NFPA No. 70-latest edition and
all local electrical codes. The unit must be electrically
grounded if an external power source is used.
In Canada, the installation must be in accordance with
standards CGA B149.1 and B149.2, installation codes for oil
burning appliances and e uipment and/or local codes. All
electrical connections are to be made in accordance with
Standard C.S.A. C22.1 Canadian Electrical Code Part 1
and/or local codes.
This Caravan application manual is intended to simplify the
selection and application of Slant/Fin modular systems for a
variety of space heating and domestic hot water re uirements.
Where any additional information is re uired, contract your
local wholesaler, Slant/Fin sales representative, or the
Slant/Fin factory.
A. Design flexibility - Caravan modular boiler systems are
available in virtually any size capacity simply by adding
modules.
B. Boiler room design, size and flexibility - since Caravan
modules have the burner and controls mounted to the
front, they can be installed with minimum clearances as per
codes, thus saving a significant amount of floor space.
C. Faster, easier installation - modules are completely
factory assembled, including individual jackets to save on-
site labor. Optional easy to install supply and return
headers with flexible uick connect fittings are available for
hot water systems.
D. afety - each module contains an individual high limit
control and a flame safeguard control. ASME relief valve is
provided separately for mounting directly on boiler.
E. Fast domestic hot water recovery - Caravan offers an
external heat exchanger of the positive circulating type.
INTRODUCTION OF FRE H WATER
Introduction of excessive amounts of fresh water into a
system can cause scaling and leave deposits in the boiler and
the surrounding pipes. This will lead to inefficient boiler
operation and breakdown. Fresh water will enter the system
as a result of hidden leaks such as may occur in underground
piping. Relief valves should be piped to a location that shows
visible signs of relief.
Process applications that use fresh water, re uire the use of
heat exchangers. Any process application that results in
introduction of fresh water into a boiler can cause scaling with
deposits forming in the boiler and surrounding piping. This will
damage the boiler. Introduction of fresh water from leaks will
cause similar damage. Use of fresh water will void warranty.
In some areas it may be necessary to use a feed water
treatment to control the corrosive makeup of the feed water.
Check with the local authority, to determine if the feed water
will need a conditioning treatment before being supplied to the
boiler.
Control Wiring Diagrams*:
SCG400, space heating only ......................................17,18
SCG400, space heating and domestic hot water .......19,20
SCG1200, space heating only ....................................21,22
SCG1200, space heating and domestic hot water .....23,24
SCG2000, space heating only ....................................25,26
SCG2000, Space heating and domestic hot water.....27,28
Field Wiring at Modules ........................................................29
Reset Ratio and Temperature Set Points .............................30
*All wiring diagrams are based on continuous circulation.
CONTENT
INTRODUCTION
Publication No. CG-10-HWO
Printed in the U.S.A. 1200
®

2
Table 1. Oil Caravan ratings hot water models — LDWO Series
(75 psi ma imum working pressure)
LDWO-600-2-5 2 4.30 602 500 2900 435 14.9 31.0 1570 2"
LDWO-750-2-6 2 5.20 728 596 3453 518 17.8 35.6 1790 2"
LDWO-850-2-7 2 6.00 840 684 3967 595 20.4 45.2 2000 3"
LDWO-900-3-5 3 6.40 896 750 4347 652 22.4 46.5 2355 3"
LDWO-1100-3-6 3 7.80 1092 894 5180 777 26.7 53.4 2685 3"
LDWO-1300-3-7 3 9.00 1260 1026 5947 892 30.6 67.8 3000 3"
LDWO-1700-4-7 4 12.00 1680 1368 7933 1190 40.9 90.4 4000 3"
LDWO-2100-5-7 5 15.00 2100 1710 9913 1487 51.1 113.0 5000 3"
LDWO-2500-6-7 6 18.00 2520 2052 11893 1784 61.3 135.6 6000 3"
LDWO-2900-7-7 7 21.00 2940 2394 13880 2082 71.5 158.2 7000 4"
LDWO-3400-8-7 8 24.00 3360 2736 15860 2379 81.7 180.8 8000 4"
Model No.
No. of
Htg.
Mod.
Firing
Rate
#2 Oil
GPH* Input
Ratings (MBH)
Gross
Output
‡ EDR
Water
( q. Ft.)
I=B=R
Net
Ratings
(MBH)†
Boiler
Horse-
power
Water
Content
(gal.)
hip
Wt.
Recom-
mended
Header
ize§
LDWO-600-2-5 215⁄887⁄32 834
3⁄84'4"
LDWO-750-2-6 25 929⁄32 837
3⁄44'4"
LDWO-850-2-7 283⁄81119⁄32 941
1⁄84'4"
LDWO-900-3-5 215⁄887⁄32 834
3⁄86'7"
LDWO-1100-3-6 25 929⁄32 837
3⁄46'7"
LDWO-1300-3-7 283⁄81119⁄32 941
1⁄86'7"
LDWO-1700-4-7 283⁄81119⁄32 941
1⁄88'10"
LDWO-2100-5-7 283⁄81119⁄32 941
1⁄811'1"
LDWO-2500-6-7 283⁄81119⁄32 941
1⁄813'4"
LDWO-2900-7-7 283⁄81119⁄32 941
1⁄815'7"
LDWO-3400-8-7 283⁄81119⁄32 941
1⁄817'10"
Model No. ‡ A B CD † L *
* 27" spacing between modules.
† Add 151⁄4" for dual fuel models.
‡ Dual fuel prefix is LWDF.
Note: Standard boiler unit prefix is LDWO.
Figure 1: Oil Caravan dimensions and typical piping/hot water models
* Light oil, 140,000 Btuh per
gallon.
† Net ratings are based on a
piping and pick-up
allowance of 1.15.
Slant/Fin should be
consulted before selecting
a boiler for installation
having unusual piping and
pick-up re uirements.
‡ Based on 150 Btuh per
s uare foot E.D.R. at
170°F average water
temperature.
§ Modules in excess of 8
are piped in parallel to first
eight.
For larger sizes, use
multiples of the above.

3
Minimum flow rate formula:
Minimum flow rate through modules =
Gross output (MBH)
20,000
Note: A water flow proving device
is recommended on all
Caravan systems.
Figure 2:
Recommended boiler piping for
variable volume zone circulation
Figure 3: Supply and return piping locations for space heat with domestic hot water
Figure 4: Instantaneous tankless coil—
two temperature with recirculation
Figure 5: Storage tank from tankless coil with recirculation
locations for space heat with domestic hot water
UGGE TED DOME TIC HOT WATER PIPING

4
EQUIPMENT INCLUDED
LDWO ERIE — Hot Water Models
Pre-assembled heat exchanger with built-in air separator.
Insulated baked enameled jacket.
Flue collector.
Draft regulator.
Flame retention oil burner with nozzle and CAD cell.
Primary burner control.
Temperature limit.
Flue brush.
Module temperature and pressure gauge.
System pressure and temperature gauge (unmounted-1 per system)
Pressure relief valve (unmounted-1 per module)
Control header (unmounted-1 per system, up to 8 modules)
OPTIONAL EQUIPMENT
Headers.
Control system.
Figure 6: Oil Caravan—optional header assembly for all models LDWO and LWDF hot water Caravan systems.
*Building piping must be rigidly secured so it cannot
move where connected to headers.
NOTE:
Shown reverse return (Preferred). For direct return,
header assembly piping connections may be made at
the same end of the boiler bank, not as shown.
Some governing agencies do not allow compression
type couplings. Consult your local code re uirements.

5
BOILER ROOM DESIGN
Caravan modular boiler systems allow better utilization of floor
space and permit future expansion with minimum cost.
Caravan modules are hand truckable, fit through doorways
and often may be installed around an existing inoperative
boiler. They can be grouped in heating module batteries of
single, multiple or angular rows. Oil-fired boiler systems
consisting of 9 or more modules should be piped in parallel in
two or more batteries. Illustrated below are typical boiler room
layouts and dimensional data on the size re uirements of oil-
fired hot water boilers.
BOILER ROOM AIR SUPPLY
To ensure safe, efficient operation, the modular boiler system
must be supplied with sufficient air to support complete
combustion, replacing air entering draft dampers or draft
hoods and ventilating the boiler room or areas.
For additional information, not listed below, see ANSI, Z223.1,
section 5.3.3.
INSTALLATION IN ENCLOSED BOILER ROOM REQUIRES
TWO UNOBSTRUCTED OPENINGS FOR PASSAGE OF
AIR INTO THE BOILER ROOM:
1. Air drawn horizontally from outdoors DIRECTLY
through an outside wall; one louvered opening near the
floor (below burner inlet) and one louvered opening near
the ceiling (above the highest draft regulator), each
opening with a minimum FREE air passage area of 1
square inch per 4000 BTUH of total system input.
2. Air drawn horizontally from outdoors through
HORIZONTAL DUCT ; one opening near the floor
(below burner inlet) and one opening near the ceiling
(above the highest draft regulator), each opening with a
minimum FREE air passage area of 1 square inch per
2000 BTUH of total system input.
3. Air drawn VERTICALLY from outdoors; one opening at
the floor and one opening at the ceiling, each opening
with a minimum FREE air passage area of 1 square
inch per 4000 BTUH of total system input.
4. Air drawn from inside the building; one opening near
the floor (below burner inlet) and one opening near the
ceiling (above the highest draft regulator), each opening
with a minimum FREE air passage area of 1 square
inch per 1000 BTUH of total system input.
IF BOILERS ARE INSTALLED ADJACENT TO OTHER
FUEL BURNING EQUIPMENT, THE AREA OF FREE
OPENINGS MUST BE APPROPRIATELY INCREASED TO
ACCOMMODATE THE ADDITIONAL LOAD.
UNLESS PROPERLY CONTROLLED, AVOID THE USE OF
FORCED VENTILATION, SINCE IT CAN CREATE AN
UNDESIRABLE PRESSURE DIFFERENTIAL BETWEEN
BOILER ROOM AND AIR SOURCE.
Figure 7. Correct location of combustion-air supply ducts

6
Figure 8. Typical layouts oil-fired systems
* Caravan can be installed as close as 1" from the wall, local codes
permitting. However, 24" is recommended for service inspection
access.
∆See Figure 1 dimensions A and D.

7
VENTING AN OIL-FIRED SYSTEM
A boiler venting system provides an escape path for the
products of combustion. In a venting system for an oil-fired
Caravan, there are three major components: a riser with draft
regulator for each module, a breeching manifold, and a
chimney.
Sometimes the venting system for a boiler plant has to be
designed to compensate for inade uate chimney conditions.
A mechanical draft inducer, properly sized and installed, can
usually increase chimney capacity sufficiently to provide
proper venting. Where a draft inducer is called for, consult
local codes and the recommendations of the mechanical draft
inducer manufacturer. Normally, a draft proving device is
necessary to permit operation of the boilers only when
ade uate draft exists.
It is important to note that when considering a mechanical
draft inducer, the boiler room air supply re uirements must be
increased. Consult the draft inducer manufacturer for this
information.
Draft Regulator
The draft regulator compensates for excessive draft that can
be caused by varying weather conditions. The regulator
should be of the barometric-draft type. Once adjusted for a
particular venting system, this type regulator automatically
compensates for excessive draft to assure optimum operating
efficiency.
Breeching
Breeching is a term used to describe a manifold(s) that
connects individual boiler modules to a chimney. Breeching is
usually constructed of sheet metal having a smooth interior
surface with all joints made tight against leakage. The layout
of a particular boiler room may re uire that the modules be
arranged in "batteries" with rows either parallel or at right
angles. Minimum breeching sizes are given in Table 2.
To avoid creating turbulent air patterns in the breeching, it is
suggested that individual boiler vent pipes be connected to
the breeching as indicated in Figure 3.
The breeching manifold should extend into, but not beyond,
the chimney liner. Round breeching is preferable to
rectangular breeching.
Chimney
Caravan oil-fired modular boilers operate efficiently with
masonry or prefabricated chimneys. This latter type of
chimney construction is generally the least expensive.
Minimum chimney sizes and heights are given in Table 2. In
addition, the chimney should be high enough to minimize the
effects of turbulent winds and high pressure areas common
near roof-top obstructions. The National Board of Fire
Underwriters recommends that the chimney should extend 3
feet above the roof and be 2 feet higher than any obstruction
within 10 feet (figure 9). The use of a vent cap where
permitted by code gives additional protection against adverse
wind conditions and precipitation.
izing Breeching and Chimneys for Oil-Fired ystems
Breeching for oil-fired Caravan systems can be either constant
size or graduated. When constant size breeching is to be
installed, refer to Table 2. The use of graduated sections may
reduce breeching costs. Generally, it becomes economically
feasible to use this approach when boiler batteries exceed
four modules. In this case, each breeching section usually
serves two to four modules.
To size graduated breeching and chimneys for a Caravan oil-
fired modular boiler system, use Table 2 and 3 and the
following procedure:
LDWO-600-2-5 2 11" 84 4'8"
LDWO-750-2-6 2 12" 101 4'8"
LDWO-850-2-7 2 13" 115 4'8"
LDWO-900-3-5 3 13" 123 7'1"
LDWO-1100-3-6 3 14" 148 7'1"
LDWO-1300-3-7 3 15" 170 7'1"
LDWO-1700-4-7 4 16" 189 9'6"
LDWO-2100-5-7 5 18" 233 11'11"
LDWO-2500-6-7 6 19" 277 14'4"
LDWO-2900-7-7 7 21" 320 16'9"
LDWO-3400-8-7 8 22" 365 19'2"
Model No. * No. of
Modules
Breeching
Diameter
Minimum
Area
(sq.in.)
Breeching
Length
* Dual fuel prefix = LWDF.
Notes:
1. For breeching and chimney sizing over 8 modules, consult factory.
2. Breeching length should be as short as possible. Measurement from the
base of the vertical vent to the nearest connected appliance should be
limited to 10' or 50% of the total vent height, whichever is greater.
Table 2. Breeching dimensions for oil-fired systems —
LDWO Series
LDWO-600-2-5 2 11" 93⁄4" X 93⁄4" 20'
LDWO-750-2-6 2 12" 91⁄2" X 131⁄2" 20'
LDWO-850-2-7 2 13" 131⁄4" X 131⁄4" 20'
LDWO-900-3-5 3 13" 131⁄4" X 131⁄4" 20'
LDWO-1100-3-6 3 14" 131⁄4" X 131⁄4" 20'
LDWO-1300-3-7 3 15" 13" X 17" 20'
LDWO-1700-4-7 4 16" 13" X 17" 25'
LDWO-2100-5-7 5 18" 163⁄4" X 163⁄4" 25'
LDWO-2500-6-7 6 19" 161⁄2" X 201⁄2" 25'
LDWO-2900-7-7 7 21" 201⁄4" X 201⁄4" 25'
LDWO-3400-8-7 8 22" 201⁄4" X 201⁄4" 25'
Model No. * No. of
Modules
Dia.
Inches
Rectangular
L x W
Inches
Minimum
Height
Feet
Chimney Liner Inside Dim. †
* Dual fuel prefix = LWDF.
† Dimensions shown are from ASHRAE Guide E uipment Handbook. Also
select inside liner dimensions to give area as great or greater than shown in
this table. Chimney height is measured from the center line of the breeching
to the top of the chimney. Chimney dimensions are approximate. They are
based on use of type "B" double wall vents, connector and manifolds; no
manifold elbows or tees; and good vent construction practices.
Field conditions vary. It is doubtful that the chimney dimensions shown here
will be suitable for all applications. Consult the 1988 ASHRAE E uipment
Handbook and Chimney Manufacturers Sizing Handbook.
Table 3. Chimney requirements

8
a) Starting with modules in the section furthest from the
chimney, count the number of modules venting into that
section of breeching.
b) Find breeching necessary to vent these boilers.
c) Count the modules venting into the next section. To this
figure add the number of modules from the preceding
section, since their output also moves through the second
section.
d) Find the correct size breeching for the second section.
e) Repeat steps (c) and (d) for each section until breeching
for the entire battery has been sized.
f) If the system has more than one battery, repeat steps (a)
through (e) for each battery.
g) Where multiple breeching runs are re uired, a section of
common breeching is often used to join the multiple runs to
the chimney. To determine the size of this piece, add up
the total number of modules feeding it, and then refer to
Table 2 or chimney manufacturer's data.
h) Find the lengths of the various sections of breeching
needed for a particular job from Table 2.
i) To calculate the length of the battery-to-chimney breeching
section, use the method applicable to the type of breeching
as follows:
• Breeching for only one boiler battery. Measure the
distance between the chimney and nearest boiler. Add
this to the figure obtained in step (h).
• Breeching to multiple runs. Measure the distance
between the chimney and the first module of the boiler
battery that is in the same axis as the common
breeching. This is the length of common breeching,
measure the distance between side of the common
breeching and nearest boiler. Add this to the figure
obtained in step (h).
j) To determine the re uired chimney dimensions, total the
number of modules in the system and refer to Table 3.
Where building height exceeds the recommended
minimum chimney height, refer to chimney paragraph.
NOTE: These procedures DO NOT take into account all
possible field conditions. As with all generalized sizing
information, the final specifications should be tempered with
the engineer's practical experience, and the chimney
manufacturer's data, and ASHRAE Handbook.
Figure 9. Suggested venting system constructions

9
FUEL OIL TORAGE FACILITIE
Local codes usually govern the installation of fuel oil storage
facilities. However, for areas where no rules have been
established, the following information can provide assistance
to the system designer.
torage tank sizing
When calculating minimum fuel oil storage capacity, several
variables must be considered. These include: maximum fuel
consumption rate, storage space limitations, availability,
distance from source of supply, and method of delivery (truck
or railroad tank car). Large storage tanks, of course, cost
more than smaller ones but the cost is not proportional (e.g.,
a 10,000 gal. tank does not cost twice as much as a 5,000
gal. tank). And larger tank capacity allows oil purchases
usually at lower per gallon rates.
Generally, the storage tank should hold enough oil to sustain
continuous operation for 10 days (plus an additional 10%
margin to allow for suction stub clearance).
To determine the minimum storage re uirement, proceed as
follows:
a) Refer to Table 1 to find the maximum hourly oil
consumption (GPH) of the system being installed.
b) Multiply the maximum hourly consumption by the probable
maximum daily hours of operation to achieve maximum
daily consumption.
c) Multiply the maximum daily consumption by 10 (days) and
add 10% to obtain the MINIMUM storage capacity.
Requirements for fuel oil storage tanks.
Data in this section is based on the use of steel storage tanks.
Where no local codes apply, take the following data into
consideration.
a) Inside tanks are usually located in the lowest part of the
building. When supply and return lines are piped through
the top of the tank, spillage is minimized in the event of
leaks.
b) Unenclosed tanks should be at least 7 feet from any open
flames or fires.
c) Most fire codes prohibit unenclosed inside tanks exceeding
275 gallons each. Where multiple tanks are installed, the
total storage capacity should not exceed 550 gallons
unless vaulted.
d) If inside tanks are properly enclosed, the maximum storage
capacity can be increased to 5,000 gallons in non-fire-
resistant buildings, and to 15,000 gallons in fire-resistant
structures.
NOTE: An enclosure shall consist of walls constructed of
6" reinforced concrete or 8-inch thick masonry with the
space between tank and walls filled with sand. If floor
above has a load-bearing capacity of 150 lbs./s . inch or
greater and is constructed of fire-resistant material, 1 foot
of sand fill over the tank is sufficient. If not, a 5-inch
concrete slab, or e uivalent, must be employed. An
alternative method is to pour a 6-inch thick concrete
enclosure directly over the tank (no air spaces).
e) Underground tanks (Figure 10) are to be buried at least 2
feet below grade.
f) Tanks buried beneath buildings ALWAYS re uire 4-inch
reinforced concrete slab covers that extend 1 foot beyond
tank in all directions.
g) Fiberglass and/or double-walled tanks may be re uired.
Check your local codes.Underground metal tanks should
be painted with heavy asphaltum, rust-resistant paint or be
of double walled construction (check local codes). DO
NOT install tank in bed of cinders (cinders contain sulphur,
which becomes corrosive when wet).
NOTE: Before installing underground tanks, check local
surface water conditions. Where potential problems exist,
concrete anchors should be provided.
FUEL OIL PIPING
Figure 10. Typical e ample of properly installed
underground fuel tank
FUEL OIL DELIVERY Y TEM
FOR INGLE FUEL BURNER
General
Three methods for delivering oil to the individual burners are
described herein. These methods are chosen to provide
tempered, filtered and air-free oil to the individual burners.
Consistent oil uality will optimize burner operation over
longer periods.
There are variations to the methods described herein which, if
applied properly, will result in acceptable operation. These
methods are for reference only. Local codes vary. It is
important to check all codes for compliance.
Information herein has been compiled using data from
industry sources, including companies such as Mitco,
Webster, Suntec and Tuthill. For additional information on
these products, contact the representative in your area.
MFG data and safety codes vary with regard to maximum fuel
unit inlet pressure. Pay particular attention to the gravity oil
head. Be sure to add oil pressure reducing valves in the
event that codes or MFG data will be exceeded. 5 psi is
e uivalent to approximately 12 feet in height. (See "H"
dimension.)
torage tank above burners (Figure 11)
A simple one pipe connection from the supply tank to each
burner helps to eliminate air in the oil line and tempers the oil
in the pipe as it travels slowly to the burners.

10
This method maintains consistent fuel oil uality to the
individual burners and therefore decreases the fre uency of
maintenance and service. When a component breakdown
occurs in a burner or in the supply system, the trouble is
easily found and service is restored uickly.
torage tank below burners and gravity tank above
burners (Figure 12)
Oil is automatically and constantly maintained in the supply tank
at a level sufficient to meet all burner needs. As oil is used, the
pressure drop is sensed by a pre-set automatic pressure switch,
which signals the booster pump to restore proper level. There is
no practical limit on the height or distance that the motorized
pump can deliver oil to the supply tank.
The great advantage of the booster pump along with a gravity
tank is that it accomplishes its purpose in the most simple and
direct manner. This results in the most economical installation,
with the shortest possible runs of pipe and wire. It also
enables the installer to adapt with ease to almost any building
configuration. A simple one pipe connection to each burner
helps eliminate air in oil line with constant flow of fuel and
tempers the oil.
Simplicity of operation of the individual burner decreases the
chances that service will be needed. When a component
breakdown occurs in a burner or in the supply system, the
trouble is easily found and service is restored uickly.
Figure 11. Storage tank above burners
Figure 12. Storage tank below burners

11
Components usually re uired are a motorized booster pump
of sufficient capacity, gravity tank and mounting hardware,
automatic oil level pressure switch, vacuum breaker and
necessary check valves and fittings. Additional information
can be obtained from Mitco Manufacturing, Hicksville, New
Yo r k .
Duplex booster pumps are desirable to provide standby
capability, in the event of booster pump failure.
izing booster pump
To determine the correct size of a booster pump:
a) Using Table 3, find maximum total firing rate of the boiler
system being installed.
b) Find the vertical and horizontal dimensions of the booster
pump's suction line.
c) Make sure the suction line lift and length are with
capabilities of typical booster pumps. Refer to Table 4.
(This data is based on Suntec models BH-1030M at 30
GPH, and BH-1050M at 50 GPH or e uivalent.)
NOTE: If lift is excessive (max. "Hg one stage, 15" Hg two
stage), contact pump manufacturer with exact
re uirements. If total length is too long, increase suction
line diameter.
d) Using Table 5, find correct supply line size.
FUEL OIL DELIVERY Y TEM
FOR DUAL FUEL BURNER
GENERAL
Dual fuel burners are shipped separately and must be field
mounted and wired. Connections to Slant/Fin control systems
can be found in the control section of this manual.
Burner set-up and mounting instructions are shipped with
each dual fuel burner. The installer must follow these
instructions.
Dual fuel burners re uire specific types of fuel oil piping
systems. The fuel oil pump is active during gas and oil
operation. Since no oil flows to the burner during gas
operation, a two pipe system keeps fuel oil in circulation,
preventing pump overheating and thermal expansion.
Figures 14 and 15 illustrate two types of two pipe fuel oil
delivery systems for dual fuel burners.
If the system is gravity feed, or if the lift is 12' or less, a single
stage pump may be selected. If the lift is 18' or less, then a
two stage fuel pump should be used. If the lift is more than
18', use a pseudo two pipe loop system (Figure 15).
TWO PIPE Y TEM (Figure 14)
An important factor to consider in a two pipe system is the
line size which depends on the maximum line length and the
total oil volume. The gear capacity of the pump is normally
uite high compared to the pump's marked capacity. For
example, an "A" pump marked for 3 GPH could have a gear
capacity of 17 GPH at 3450 RPM.
For a Caravan system, it is ideal to have individual supply and
return fuel lines for each boiler. In practice, one can opt to
have not more than 3 boilers on a single supply or suction line
and a common return for 6 to 9 boilers . (Figure 14)
Table 8 is the calculated line lengths for two types of "B"
pumps with different gear capacities. For example, if the lift is
10', the furthest boiler 150' and the fuel oil pump is two stage,
of type B89 series, then the corresponding line length from
the table is 161' for 5/8" tubing.
Figure 13. Wiring diagram for gravity feed
booster-pump operation
0 - 7' 100' 63'
8 - 10' 80' 53'
11 - 13' 63' 41'
14 - 15' 52' 34'
Vertical
Lift (2)
Firing Rates
up to 30 GPH (5)
Firing Rates
up to 50 GPH (6)
Maximum Total uction Line Lengths (3)
1/2" O.D. copper tubing (4)
Table 4. Ma imum booster pump suction line length (1)
25' 1⁄2" O.D. tube 1⁄2" O.D. tube
75' 1⁄2" pipe 1⁄2" pipe
200' 3⁄4" pipe 3⁄4" pipe
Total Length
Maximum
Firing Rates
up to 30 GPH (5)
Firing Rates
up to 50 GPH (6)
Table 6. Boiler feed line sizes (9)
Up to 30 GPH (5) 300' 800' 2500'
Up to 50 GPH (6) 175' 350' 1500'
Supply Line Size 1⁄2" O.D. tube 1⁄2" pipe 3⁄4" pipe
Firing Rate Maximum Total upply Line Length (8)
Table 5. Supply line sizes for high-volume fuel oil
delivery systems (7)
(1) Defined as the connection distance between storage tank and inlet of
booster pump.
(2) Height of booster pump inlet above bottom of storage tank. If higher lift is
needed, contact booster pump manufacturer with exact re uirements.
(3) Total suction length e uals vertical lift plus horizontal distance between
suction line connection at storage tank and inlet of booster pump.
(4) 5/8" tubing allows maximum horizontal distance between supply tank outlet
and booster pump inlet to be safely increased by 250%.
(5) Maximum fuel oil consumption rate with Suntec BH-1030M pump.
(6) Maximum fuel oil consumption rate with Suntec BH-1050M pump.
(7) Supply line is defined as the connection between the outlet of the booster
pump and the inlet of the supply tank.
(8) Total supply line length e uals vertical lift plus horizontal distance between
booster pump outlet and supply tank inlet.
(9) Boiler feed line is defined as the connection between the gravity feed tank
and the furthest burner.

12
NOTE: NFPA re uires that the pump inlet pressure not
exceed 3 psi. Therefore, when oil is fed by gravity from above
the pump, the height should not be more than 8' from the
pump to the top of fuel oil supply. If it is more than 8', then
one way to protect the pump is to have a vacuum operated
safety valve (OSV) on each fuel unit.
P EUDO TWO PIPE LOOP Y TEM (Figure 15)
Another way to prevent overheating and thermal expansion of
the oil while the unit is running on gas for extended periods, is to
use a pseudo two pipe loop system (Figure 15). This system
uses a booster pump to circulate the oil from the tank to a
header that feeds the burners. Excess oil is fed back to the
tank. Generally, a 1/2" fuel line should handle most installations
within 200' when using a type "A" pump. A duplex pump-motor
boost system should be wired to run for oil as well as for gas.
Whenever a burner (regardless of fuel) is running, one of the
duplex pump motors should be activated and another pump
motor should serve as an automatic backup.
Gas 620 620 500 2900 435 14.9 31.0 1650 2"
Oil 4.30* 602
Gas 750 750 592 3433 515 17.7 35.6 1870 2"
Oil 5.20* 728
Gas 800 800 622 3607 541 18.6 45.2 2080 3"
Oil 6.00* 840 674 586 20.1
Gas 930 930 750 4347 652 22.4 46.5 2475 3"
Oil 6.40* 896 3680 682
Gas 1125 1125 888 5147 772 26.5 53.4 2805 3"
Oil 7.80* 1092
Gas 1200 1200 933 5407 811 27.9 67.8 3120 3"
Oil 9.00* 1260 1011 5860 879 30.2
Gas 1600 1600 1244 7213 1082 37.2 90.4 4160 3"
Oil 12.00* 1680 1348 7813 1172 40.3
Gas 2000 2000 1555 9013 1352 46.4 113.0 5200 3"
Oil 15.00* 2100 1685 9767 1465 50.3
Gas 2400 2400 1866 10820 1623 55.7 135.6 6240 3"
Oil 18.00* 2520 2022 11720 1758 60.4
Gas 2800 2800 2177 12620 1893 65.0 158.2 7280 4"
Oil 21.00* 2940 2359 13673 2051 70.5
Gas 3200 3200 2488 14420 2163 74.3 180.8 8320 4"
Oil 24.00* 3360 2696 15627 2344 80.5
Model No.
No. of
Htg.
Mod. Fuel
Firing
Rate
CCFH
GPH Input
Gross
Output
‡ EDR
Water
( q. Ft.)
I=B=R
Net
(MBH)†
Horse-
power
Water
Content
(gal.)
hip
Wt.
Recom-
mended
Header
ize§
Table 7. Dual Fuel Caravan Ratings Hot Water Models - LWDF Series (75 psi ma imum working pressure)
LWDF-600-2-5 2
LWDF-750-2-6 2
LWDF-850-2-7 2
LWDF-900-3-5 3
LWDF-1100-3-6 3
LWDF-1300-3-7 3
LWDF-1700-4-7 4
LWDF-2100-5-7 5
LWDF-2500-6-7 6
LWDF-2900-7-7 7
LWDF-3400-8-7 8
Ratings
* Light oil, 140,000 Btuh per gallon.
† Net ratings are based on a piping and pick-up allowance of 1.15.
Slant/Fin should be consulted before selecting a boiler for installation having unusual piping and pick-up re uirements.
‡ Based on 150 Btuh per s uare foot E.D.R. at 170°F average water temperature.
§ Modules in excess of 8 are piped in parallel to first eight.
For larger sizes, use multiples of the above.
1' 118 99 328 276
2' 113 95 313 263
3' 107 90 298 250
4' 102 86 283 237
5' 96 81 268 225
6' 91 76 253 212
7' 86 72 238 200
8' 80 67 222 187
9' 75 61 207 174
10' 69 58 192 161
11' 64 54 177 148
12' 58 49 162 136
13' 53 44 147 123
14' 47 40 131 110
15' 42 35 116 98
Two Pipe
Lift Ht.
1/2" O.D. Tubing
A B
5/8" O.D. Tubing
A B
A = B82 Series Suntec Pump 63 GPH gear capacity.
B = B89 Series Suntec Pump 75 GPH gear capacity.
Table 8. Line Length for Two-Stage Fuel Unit

13
Figure 14. Dual Fuel Piping Two Pipe
Figure 15. Pseudo Two-Pipe Loop System

14
CONTROLS
THE BOILER TAGING CONCEPT
The heart of the Caravan boiler plant is a temperature-
actuated control system that automatically stages only those
boiler modules needed to meet the heating demand in a given
period, thereby conserving fuel.
In a staging control system, each stage ordinarily activates
one boiler module. With appropriate wiring, multiple modules
can be grouped within a stage.
During a fluctuation in heating re uirements, a large central
boiler cycles on and off to match heat output to building
demand. A staged modular boiler system, on the other hand,
will energize only as many modules as the system load
re uires. Only one stage cycles at a time. The other stages
remain off or operate continuously, thereby performing at peak
efficiency. For example, in a 10 module boiler system, with the
heating load at 61% of capacity, six of the modules operate
continuously at peak efficiency. Fractional heating
re uirements are supplied by the seventh "cycling" module,
while the remaining three modules are "off." This is in
contrast to a single large central boiler that simply cycles on
and off, resulting in lower efficiency.
Over-sizing is a major factor in poor system efficiency. Most of
the time a single central boiler is oversized. Historical data
shows that many single central boilers are considerably
oversized even at the outdoor temperature for which they
were designed. Modular boiler systems are not oversized by
more than a portion of one module, regardless of the load.
The Caravan control system automatically compensates for
seasonal temperature changes. It energizes more or fewer
boilers, depending on changes of outside temperature, system
water temperature, or both. Modules save energy by
operating in long cycles at full-rated output and maximum
efficiency.
CONTROL Y TEM ELECTION
There are three levels of Caravan System Controls (SC). The
choice of one system over another depends on several
factors: The type of boilers (hot water or steam, gas or oil),
the number of stages and modules involved, and the relative
importance of installation costs, fuel economy and occupant
comfort as design objectives. Caravan modular boiler control
systems are not intended to be the sole building temperature
control. Zone controls are re uired.
400 ERIE CONTROL Y TEM
The 400 series control system provides staging operation to
regulate system water temperature with a fixed-ratio, single
stage outdoor reset control. The 400 series control is
primarily for small to medium sized (2, 3 or 4 boilers) gas-fired
Caravan systems, where lead/lag is not critical. The supply
water temperature is automatically adjusted up or down based
on outdoor temperature. Multiple outdoor temperature
controls actuate the number of heating modules needed,
depending on outdoor temperature. These modules are then
cycled as a group by the outdoor reset control.
The outdoor reset control has two sensors; one 30 foot long
sensor monitoring the outdoor temperature, and one 10 foot
long sensor monitoring the system water temperature. The
reset ratio is nonadjustable and generally sufficient to provide
ade uate space heating in most climates.
The SCG400 system control group includes the specified 400
series control panel(s) plus all operating and safety controls
listed in the bill of materials.
BILL OF MATERIAL - CG400
pace heating only
1 — Temperature reset control, T475A, for north wall (with
sunshield).
* — Outdoor temperature control, T675A, for north wall (with
sunshields). * One for each space heating module, in
excess of one.
1 — System enable temperature control, T675A, for north
wall (with sunshield).
1 — Low water cutoff, PS-851M-120.
1 — Manual reset hi-limit, L4006E.
pace and domestic hot water heating
1 — Temperature reset control, T475A, for north wall (with
sunshield).
* — Outdoor temperature control, T675A, for north wall (with
sunshields). * One for each space heating module, in
excess of one.
1 — System enable temperature control, T675A, for north
wall (with sunshield).
1 — Low water cutoff, PS-851M-120.
1 — Manual reset hi-limit, L4006E.
1 — Domestic hot water, temperature control, L6006A.
1 — Domestic hot water motorized valve, EMV II.
Relays re uired are to be field furnished. See wiring diagram.
1200 ERIE CONTROL Y TEM
The 1200 series control system is an extremely accurate and
flexible multi-stage microprocessor based control system with
automatic lead/lag, designed to se uence heating modules
based on outdoor air temperature and supply water
temperature. This control is generally applied on systems with
up to 10 modules. The SC1200 panel consists of a
microprocessor mounted in a sheet metal box with ade uate
wiring knockouts. The panel is furnished with outdoor sensor
and water temperature sensor. In the event of a power failure,
the control turns all stages off with a time delay between
stages for starting when power is restored. The SC1200 panel
has an adjustable reset ratio, control band and set point and
controls 2 through 6 stages. When used with the EC1200 4-
stage expansion panel, up to 10 stages of operation are
provided. Individual stage indicating lights are visible with
panel cover removed. Desired number of stages can be set in
the field. On systems re uiring automatic lead/lag and
domestic hot water or for systems with more than 10 modules,
the 2000 series control system is recommended. If Domestic
Hot Water is used with the 1200 series control system,
lead/lag must be disabled.
The SCG1200 system control group includes the specified
1200 series control panel(s) plus all operating and safety
controls listed in the bill of materials.

15
BILL OF MATERIAL - CG1200
pace heating only — 2-6 modules
1 — Microprocessor, 2-6 stage standard system control
panel SC1200.
1 — Outdoor temperature sensor, C7031G.
1 — Supply water temperature sensor, C7170A.
1 — Supply water temperature sensor well and housing,
C7031D.
1 — System enable temperature control, T675A, for north
wall (with sunshield).
1 — Low water cutoff, PS-851M-120.
1 — Manual reset hi-limit, L4006E.
In addition to the above, the following additional components
are provided for systems with 7 to 10 modules.
1 — Microprocessor, 7-10 stage standard expansion control
panel, EC1200.
OPTIONAL ACCESSORIES
Pump Control (SC 1200 series only)
• automatic pump failure change-over.
• manual pump selector switch.
• alarm circuit and light.
Test plug kit
• speed up testing and troubleshooting.
Consult factory for other desired options.
2000 ERIE CONTROL Y TEM
The 2000 series control system is a factory-wired multi-stage
microprocessor controlled system which incorporates all the
components and features of the 1200 series control system,
plus visual display readout and provisions for domestic hot
water with automatic lead/lag and night set-back features. The
system control panel (SC2000) is a NEMA-1 enclosure with a
hinged door and keyed lock. Visible indicator lights identify
power, heat and active stages. The components are factory
wired to a terminal strip that is clearly numbered for
connection to common system components such as system
enable temperature control, manual reset high limit, low water
cutoff and accessory panels such as dual pump control. Two
types of lead/lag are featured:
• LEAD/LAG (FOFO): When all boilers are off and a call for
heat occurs, the stage following the last stage off will be the
first stage on; use this selection when it is important to
evenly distribute boiler operating time.
• STD (FOFO): When all boilers are off and a call fo heat
occurs, Stage 1 (closest to the chimney) is always first
stage on.
The SCG2000 system control group includes the 2000 series
control system panel plus all operating and safety controls
listed in the bill of materials.
BILL OF MATERIAL - CG2000
All SCG2000 Systems Control Groups have the following
standard components:
1 — Microprocessor, 2-4 stage deluxe system control panel
OR
1 — Microprocessor, 2-8 stage deluxe system control panel
PLUS
1 — Outdoor temperature sensor and system enabler
1 — Supply water sensor
The SCG2000 System include:
1 — Low water cutoff
1 — Manual reset hi-limit
Other options include:
• Indoor space sensor for non-zoned systems
• Stage relays
• Components for domestic hot water include:
EMV II motorized valve
DHW thermostat
Circulators, relays, switches and other wiring devices are
provided by contractor.

16
EQUENCE OF OPERATION - CG400
pace heating only
When outdoor temperature falls below the setting of the system
enable temperature control (T675A), the system is activated. The
outdoor reset control (T475A) will energize module #1 and regulate
the supply water temperature. As the outdoor temperature continues
to drop below the settings of the individual module temperature
controls (T675A), more stages are energized. The energized
modules are cycled as a group by the outdoor reset control (T475A).
POWER SUPPLY, PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
SEE FIGURE C1 FOR WIRING TO MODULE X X
CONNECTIONS.
SET SYSTEM ENABLE THERMOSTAT (T675A) AT
THE TEMPERATURE THAT THE BUILDING WILL
BEGIN TO REQUIRE HEAT (NORMALLY BETWEEN
40° F AND 60° F). MOUNT OUTDOOR SENSING
BULB ON NORTH (SHADED) WALL IN SUNSHIELD
#34886A.
LOW WATER CUTOFFS MUST BE INSTALLED AT A
LOCATION HIGHER THAN THE TOP OF THE
BOILERS.
ON SYSTEMS WITH MULTIPLE LOW WATER CUT-
OFFS AND/OR MANUAL RESET HIGH LIMITS,
REFER TO FIGURES C2 AND C3 PAGE 29 FOR
PROPER WIRING.
ON SYSTEMS WITH ONE LOW WATER CUTOFF,
INSTALL A JUMPER BETWEEN TERMINALS 1 AND 3
ON THE LOW WATER CUTOFF.
1
2
4
7
6
CG-400- -4 CARAVAN CONTROL Y TEM WIRING DIAGRAM
• Up to 4 space heating modules
T675A SETTING
Determine the proper setting of
each T675A thermostat by calculating
the percentage of the total heating load
that each T675A will energize and
apportion this over the operating
temperature range (enable temperature
minus design outdoor temperature).

17
CG-400- -4 CARAVAN CONTROL Y TEM LADDER DIAGRAM

18
POWER SUPPLY, PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
SEE FIGURE C1 FOR WIRING TO MODULE X X CONNECTIONS.
SET SYSTEM ENABLE THERMOSTAT (T675A) AT THE
TEMPERATURE THAT THE BUILDING WILL BEGIN TO REQUIRE
HEAT (NORMALLY BETWEEN 40° F AND 60° F). MOUNT OUTDOOR
SENSING BULB ON NORTH (SHADED) WALL IN SUNSHIELD
#34886A.
LOW WATER CUTOFFS MUST BE INSTALLED AT A LOCATION
HIGHER THAN THE TOP OF THE BOILERS.
ON SYSTEMS WITH MULTIPLE LOW WATER CUTOFFS AND/OR
MANUAL RESET HIGH LIMITS, REFER TO FIGURES C2 AND C3
PAGE 29 FOR PROPER WIRING.
ON SYSTEMS WITH ONE LOW WATER CUTOFF, INSTALL A JUMPER
BETWEEN TERMINALS 1 AND 3 ON THE LOW WATER CUTOFF.
DOMESTIC HOT WATER (DHW) BOILERS CYCLE AS A GROUP
THROUGH FIELD SUPPLIED RELAY(S). SEE WIRING DIAGRAMS
FOR CONNECTIONS. EACH DHW BOILER REQUIRES A DRY
CONTACT CLOSURE. THIS CAN BE DONE WITH INDIVIDUAL
RELAY(S) FOR EACH BOILER OR WITH A SINGLE RELAY WITH DRY
CONTACTS FOR EACH DHW BOILER(S) AS SHOWN. RELAY(S) ARE
FIELD SUPPLIED AND MUST HAVE A 120 VOLT COIL.
SET DHW CHANGEOVER THERMOSTAT DESIRED TEMPERATURE
FOR DOMESTIC BOILERS TO CONTRIBUTE TO THE SPACE
HEATING LOAD.
EQUENCE OF OPERATION - CG400
pace heating and domestic hot water
Domestic modules maintain hot water year round through a L6006A
a uastat, mounted in the boiler return pipe of the DHW heat
exchanger. When outdoor air temperature falls below the setting of
the system enable temperature control (T675A), the space heating
system is activated. The outdoor reset control (T475A) will energize
module #1 and modulate the supply water temperature based on
outdoor temperature. As the outdoor temperature continues to drop
below the settings of the individual module temperature controls
(T675A), more modules are energized. The energized modules are
cycled as a group by the reset control. When the final outdoor
temperature control (T675A) calls, and domestic hot water
temperature control (L6006A) is satisfied, the motorized valve
opens, allowing the domestic water modules to contribute to space
heating.
1
2
3
4
5
6
7
CG-400-D-4 CARAVAN CONTROL Y TEM WIRING DIAGRAM
• Domestic hot water and space heating
• Up to 4 space heating modules

19
CG-400-D-4 CARAVAN CONTROL Y TEM LADDER DIAGRAM

20
Y TEM CONTROLLER C1200
SC-1200 panel is factory e uipped for 6 stage operation. To change
the number of operating stages the appropriate resistor must be
installed in the SC1200 panel, on the microprocessor control,
across terminals 7 and 8. Resistors for 1 through 5 stages are
shipped with the SC1200 panel. Resistors for 7 through 10 stages are
shipped with the SC1200 panel. See Table C3.
For proper control settings refer to Tables C1 and C2.
Microprocessor control has a two minute time delay between stages.
For rapid testing and troubleshooting, the control may be temporarily
sped up by using a TP1 test plug kit. Order Slant/Fin part number
411006 (Honeywell part number 4074EDJ).
This control is e uipped with automatic lead/lag which constantly
rotates the boiler firing order to ensure even wear. The automatic
lead/lag function can be disabled by installing a jumper in the SC1200
panel, on the microprocessor control, across terminals 9 and 10.
IMPORTANT
For more detailed information, refer to the manufacturer’s data packed
with each component.
EQUENCE OF OPERATION - CG1200
pace heating only
When outdoor temperature falls below the setting of the system
enable temperature control (T675A), the system is enabled. The
1200 series control system energizes the necessary modules to
maintain sufficient supply water temperature based upon outdoor
air temperature demand. As outdoor air temperature changes, the
system will automatically increase or decrease the number of
operating modules until supply water temperature meets outdoor air
temperature demand. The control system also operates the boilers
with automatic lead/lag, ensuring e ual run-time for each boiler. If
desired, the automatic lead/lag can be disabled by installing a
jumper, on the microprocessor control, across terminals 9 and 10.
C-1200- -06-06 CARAVAN CONTROL Y TEM WIRING DIAGRAM
• Up to 6 space heating modules
• Up to 6 stages
REFER TO FIG. C1 ON PG. 29 FOR WIRING AT MODULES.
CONTACTS REFLECT CLOSED VALVE.
R AND W MAKE ON TEMP. RISE ABOVE SETPOINT.
CONTACT OPENS AT HIGH LIMIT SETTING.
RELAYS REFLECT DE-ENERGIZED MODE
REMOTE SENSOR (USE SHIELDED CABLE)
ON SYSTEMS WITH MULTIPLE LOW WATER CUTOFFS AND/OR MANUAL RESET
HIGH LIMITS, REFER TO FIG. C2 AND C3 FOR PROPER WIRING. ON SYSTEMS WITH
ONE L.W.C.O. INSTALL A JUMPER BETWEEN TERMINALS 1 AND 3 ON THE L.W.C.O.
ASSEMBLED 6" WIRE AND 1/4" FEMALE QUICK CONNECTORS ARE PROVIDED FOR
CONNECTION TO FIELD WIRING ON SC1200 AND EC1200 PANELS. (WIRE NUTS BY
CONTRACTOR)
1
2
3
4
5
6
7
8