Central Boiler Titanium Series User manual

SAVE THESE INSTRUCTIONS
(p/n 9000600 - REV. C) - 28-JUN-2019
For parts and accessories, service or repairs, call your authorized Central Boiler dealer or heating contractor. Record the information
below for future reference.
Model Serial Number Installation Date
Dealership Name Phone Number
Owner Name
Some of the information provided in this guide is for reference only. Your actual furnace may dier from those
represented here. ALWAYS refer to your Owner's Manual for information specic to your furnace.
CENTRAL BOILER OUTDOOR FURNACE
INSTALLATION AND
INITIAL WATER TREATMENT GUIDE

CENTRAL BOILER ONLINE RESOURCES
Enter the web address in your browser or scan the code using any QR code reader app on your smartphone
to access Central Boiler's library of information to help with installation, operation and maintenance of your
Central Boiler outdoor furnace.
Detailed Furnace Installation Variations
https://CentralBoiler.com/explore/furnace-installation/
View and/or download PDFs to assist in installation of your outdoor furnace. Information and examples
regarding pumps, foundations, chimneys and support structures, ermoPEX piping, and example
congurations for a variety of heating congurations.
Online Support Center
https://CentralBoiler.com/support/
Enter your furnace serial number and nd articles, answers, parts and more information.

How to Use This Guide
Contents
Important Precautionary Information .................................................iv
PLANNING THE LOCATION ............................................................ 1
INSTALLATION PRECAUTIONS....................................................................2
Chimney Recommendations ....................................................................2
GENERAL INSTALLATION INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Potable Water ................................................................................3
1650XL Inhibitor Plus ..........................................................................3
MolyBoost ...................................................................................3
Adding Antifreeze to Outdoor Furnace System .....................................................4
Fittings forTitanium Series Models...............................................................5
Shut-O Valves ...............................................................................5
Ground Rod Kit ...............................................................................5
Supply and Return Lines .......................................................................5
Temporary Above Ground or Winter Installations...................................................6
Digging the Trench ............................................................................6
Underground Electric Wire ......................................................................7
Connecting to Existing Heating System ...........................................................7
SYSTEM COMPONENTS ............................................................... 8
Plan with your heating system in mind ...........................................................8
Pump Selection ...............................................................................8
Pump Installation Guidelines ...................................................................9
Selecting Pump Location ......................................................................10
Ports on Outdoor Furnace......................................................................12
PEX Fittings andTools.........................................................................12
Shut-o Valves ..............................................................................13
Optional Thermostatic Valve ...................................................................13
Manual Air Bleeders ..........................................................................14
CONNECTING TO EXISTING SYSTEMS ................................................... 15
Water Heater ................................................................................15
Existing Forced Air Installations ................................................................16
Water Flow..................................................................................16
Items of Note in Forced Air Installations..........................................................16
Installing Thermostatic Controls for Forced-Air System .............................................19
Heating Multiple Zones .......................................................................23
Hydronic Systems ............................................................................24
Filters ......................................................................................24
Evaluate Your Existing System Before Installation .................................................24
Connecting to an Existing Boiler System - Pressurized..............................................25
Connecting to an Existing Boiler System -Vented .................................................27
Connecting to Hydronic Baseboard Heaters.......................................................29
Hydronic Radiant Systems .....................................................................31
Pool and/or Hot Tub Heating ...................................................................35
FINALIZING THE INSTALLATION ....................................................... 38
1. Test Supply Water ..........................................................................38
2. Remove Strapping Securing the Vent Cap ......................................................38
3. Check for Leaks ............................................................................38
4. Cover Supply and Return Lines ...............................................................39
5. Adding Initial Water Treatment...............................................................39
6. Fill Outdoor Furnace with Water and Purge Air..................................................40
7. Immediately Heat the SystemWater to 185˚F (85˚C) ............................................45
8. Test the Treated System Water in the Outdoor Furnace ...........................................46
9. Titanium Series Models - Send in Water Sample.................................................47
How to Use This Guide
e guide is divided into sections
to help with the installation of the
outdoor furnace and connection
to an existing heating system. e
information provided here represents
common installations, components
and heat emitters. Every system will
be dierent. If questions arise that
are not answered with this guide,
consult with your dealer and/or a
heating professional.

Central Boiler Outdoor Furnace Installation Guide
Important Precautionary Information
Be sure to read carefully and understand these precautions before, during and after the installation, operation
and maintenance of the furnace.
NOTE: All installations must be in accordance with local and
state codes which may dier from the information in this
manual.
NOTE:Anyelectricalinstallationshould bedone byaqualied
installer in accordance with applicable codes.
Do not attempt service inside the electrical control panel
without rst disconnecting the electrical power at the
main power source.
This outdoor furnace is not intended or certied to be
installed inside habitable space. Do not install the outdoor
furnace inside your home.
This outdoor furnace should not be installed in a building
that could be damaged or where a nancial loss could
occur from smoke, soot, re or water.
This outdoor furnace and/or chimney must not be installed
inside or under any conguration or construction that
contains combustible materials as part of the structure
or conguration. The chimney is not intended or safety
tested to be used or installed other than on the furnace
located outside of any structure or enclosure.
Disconnect the electrical power to the outdoor furnace
before replacing an electrical component.
When installing a heat exchanger on an existing hot water
boiler or in a forced air system, be sure none of the existing
system safety controls are disabled.
NOTE: Any changes to an existing boiler system should be
done be a qualied installer in accordance with applicable
codes.
Maintain the following clearances from combustibles for
the furnace installation:
• 44" (112 cm) from the back
• 12" (30.5 cm) from the sides
• 48" (122 cm) from the front
• 18" (46 cm) from chimney inspection cover
• The foundation must be noncombustible
• Refer to your Owner's Manual for recommended
maintenance clearances
Do not allow combustible materials (straw, hay or wood)
near the outdoor furnace. Keep the perimeter of the
outdoor furnace clear and clean.
For re safety, keep all combustible materials at least
six feet (two meters) away from the outdoor furnace,
especially around the door area. Debris of wood chips and
other combustibles in the area may be easily ignited if a
hot coal is spilled out of the rebox and left unnoticed.
CAUTION
This outdoor furnace is not intended to be connected to a
chimney ue serving another appliance.

1
Central Boiler Outdoor Furnace Installation Guide
PLANNING THE LOCATION
When selecting a suitable location, carefully consider each of the
following:
• Must be installed in accordance to all applicable codes and
regulations.
• Check with your insurance company to see if they have any
location requirements.
• Consider prevailing winds and the direction smoke will travel.
• e shorter the distance between the outdoor furnace and
building(s) being heated, the lower the cost will be for the
installation of the hot supply and return water lines, and
ermoPEX insulation.
• Be sure to maintain the required clearances to combustibles and
recommended maintenance clearances.
• ermoPEX pre-insulated piping is recommended for all
installations. Other types of insulated pipe congurations may
result in high heat loss and increased wood consumption.
• If the ground at the location is unstable or subject to frost
heaving, consider installing 2" (5 cm) closed-cell insulation
under the front portion of the concrete slab the outdoor furnace
will be installed on, and under the area around the slab used
for walking. Your Owner's Manual has more information about
foundations and foundation dimensions.
• If installing an LP tank (for an optional gas-red wood ignition
system, for example), carefully consider the location of, and
the distance to, the LP tank. Refer to your Owner's Manual for
more information.
Before You Begin
To ensure your Central Boiler
outdoor furnace functions as
designed, careful planning and
proper installation are imperative.
is section outlines much of
the information needed to install
the outdoor furnace, select water
lines, install circulation pumps
and connect to your existing heat
emitter(s).
Some of the information provided
in this Installation Guide is for
reference only. For example,
illustrations of furnaces are meant
to be for reference only; your actual
furnace may be dierent.
Always refer to your Owner's
Manual for information specic to
your furnace.
Be sure to read carefully and observe
all of the information, not only in
this guide, but in the entire Owner's
Manual.
If any installation questions arise
that cannot be answered by the
information in this manual, be sure
to contact your dealer.
Optional Gas-red Wood Ignition
Most furnaces can be tted with an
optional gas-red wood ignition.
With just the push of a button, the
power ignition will light the re. It
will also automatically relight the re
if needed, even when you are away
from home. See your dealer for more
information.

2Central Boiler Outdoor Furnace Installation Guide
INSTALLATION PRECAUTIONS
A qualied installer must perform the installation of this supplementary
outdoor furnace and must determine how to install it to be compatible
with the existing heating source.
Chimney Recommendations
NOTE: Chimney recommendations provided here are general in nature. You
should refer to your Owner's Manual for model-specic recommendations and
requirements.
In higher populated areas, extend the chimney to a height above
the roofs of surrounding buildings. Use Central Boiler Chimney
Extensions when extending the chimney. When only the standard eight
feet (2.4 m) of chimney are used, the sections must be secured at the
connection joint with four (4) screws to stabilize the extension.
If extensions are added to the standard eight feet (2.4m) of chimney,
the chimney should be reinforced appropriately. Refer to the Owner's
Manual for chimney support recommendations when three or more
sections are used. When adding sections of chimney, make sure that
there is nothing within the fall zone of the chimney that could be
damaged. If something is located within the fall zone and cannot be
removed, guy wires or braces may need to be installed to prevent a
falling chimney from causing damage.
NOTE: If more than three 4-foot (1.2-m) sections of chimney are used, a support
(e.g., a pole, pipe or other structural support) may be installed from the ground
that can withstand wind.
NOTE: For chimney extensions or chimney replacement, use only genuine Central
Boiler chimney components. Parts are available from an authorized Central Boiler
dealer.
e installation of a spark arrester is recommended, particularly where
there are dry conditions or where there is combustible material near
the unit, unless the installation of a spark arrester is prohibited by local
requirements. Use common sense to avoid potential res, including
exercising caution when disposing of ashes, cleaning and refueling.
Keep all highly combustible materials (e.g., gasoline, propane, leaves,
pine needles, etc.) away from an operating unit at all times. Take special
precautions in windy conditions.
If a spark arrester is used, it must be kept clean enough to allow
unrestricted exhaust ow.
Do not use any combustible
materials for the foundation.
CAUTION
Outdoor furnace must be installed on a noncombustible surface
or foundation that incorporates an enclosure that will prevent
supply and return lines from possible exposure to sunlight, fire,
or physical damage that may be caused by an occurrence
outside the outdoor furnace enclosure. Foundation may consist
of concrete, crushed rock, or patio blocks.
EXAMPLE
(Foundation Optional)
Front
Foundation or No Foundation?
Some outdoor furnaces may
be installed without a concrete
foundation, while some require
a foundation (see your Owner's
Manual). Even if a foundation is
not required, installing the outdoor
furnace on a foundation oers many
advantages to placing it directly on
stable, level ground. e outdoor
furnace is less likely to move due to
frost heaving. A foundation keeps
the area directly around the outdoor
furnace free of standing water and
can help to keep unwanted pests out.
It can also raise the furnace up to
provide a more comfortable height of
the rebox door opening.
is is an example of a foundation
illustration. See your Owner's
Manual for foundation information
for your model.

3
Central Boiler Outdoor Furnace Installation Guide
GENERAL INSTALLATION INFORMATION
Potable Water
If the outdoor furnace is to heat potable water associated with
commercial food preparation or for heating milk-house hot water, it is
recommended to install a double-wall heat exchanger. Also, when lling
the system with water, a back ow preventer must be installed in the line
used for lling.
1650XL Inhibitor Plus
To aid in protecting the system from corrosion, it is imperative to add
Central Boiler 1650XL Inhibitor Plus (p/n 1650) when initially lling
the system. Your Owner's Manual will identify the recommended
amount of 1650XL Inhibitor Plus for your furnace.
Any time water is added to the system, 1650XL Inhibitor Plus must be
added if a tested water sample indicates it is necessary.
1650XL Inhibitor Plus is composed of common materials and is
biodegradable. However, in keeping with good safety and environmental
practices, the supplier recommends the following if draining treated
system water becomes necessary:
• You may drain the outdoor furnace to a home septic system. Central
Boiler 1650XL Inhibitor Plus is biodegradable and can be properly
treated in a residential septic system. If doing so, however, be careful
not to overow the septic system.
• Do not drain the outdoor furnace in such a manner that the drain
water could in any way contact surface water, stream, river, estuary
(where a river meets a sea), lake, pond, ocean or other types of waters.
• Do not drain to any location within 50 feet (15 meters) of any water
well.
MolyBoost
MolyBoost is an additive that enhances the corrosion protection
properties of 1650XL Inhibitor Plus. When used with 1650XL Inhibitor
Plus, it provides more protection than using 1650XL separately.
MolyBoost does not provide adequate protection alone without
1650XL.
Your Owner's Manual will identify the recommended amount of
MolyBoost for your furnace.
1650XL Inhibitor Plus
1650XL Inhibitor Plus
1650XL Inhibitor Plus polymer solution
provides superior corrosion protection for
the furnace and helps protect exchangers
and pumps against solids adhering to
system parts.
1650XL Inhibitor Plus
MolyBoost
MolyBoost is an additive that enhances
the corrosion protection properties of
1650XL Inhibitor Plus. When used with
1650XL Inhibitor Plus, it provides more
protection than using 1650XL separately.
MolyBoost does not provide adequate
protection alone without 1650XL.
For stainless Titanium Series outdoor
furnaces, adding MolyBoost as part of the
initial treatment is required.

4Central Boiler Outdoor Furnace Installation Guide
Adding Antifreeze to Outdoor Furnace System
Most outdoor furnaces are installed without antifreeze when an existing
heating system is in place and there is no anticipation of leaving the
outdoor furnace unattended for extended periods of time (10 days or
more). If the building being heated has an alternate heat source, system
water may be kept from freezing by running the circulating pump(s)
and drawing heat from the existing furnace or boiler in the home or
building.
To prevent freezing if the outdoor furnace is not red for extended
time periods or if lengthy power outages are anticipated during cold
weather, a nontoxic propylene glycol boiler-type may be used in the
system. Some types of antifreeze that contain various inhibitors have
been known to create problems like coagulation and jelling. To prevent
potential problems, do not use propylene glycol that is premixed
with inhibitors. Central Boiler 1650XL Inhibitor Plus (p/n 1650) is
compatible with (raw) propylene glycol. It is important to use 1650XL
Inhibitor Plus with straight propylene glycol for corrosion protection.
If adding antifreeze to the system, it is imperative that the entire system
contain at least 30% antifreeze concentration mixed with softened,
reverse osmosis or deionized water to prevent bacterial growth and
minimize minerals in the system. Bacterial growth is likely to occur
with low antifreeze concentrations and can cause corrosion in the
furnace water jacket and/or clogging of heat exchangers. To conrm the
antifreeze solution is adequate and to kill bacteria, immediately heat the
system up to 185˚ F, allow the pumps to circulate for at least 24 hours
and then obtain a sample of the system water. Using an antifreeze tester,
the solution must be protected to 10˚F (-12˚C) or below.
NOTE: If using antifreeze, test the pH and nitrite levels once each month.
NOTE: Be sure to adhere to all warnings and precautions on the antifreeze label.
NOTE: Do not use automotive or RV types of antifreeze.
NOTE: If using antifreeze, use Test Kit (p/n 597) when testing the treated water in
the outdoor furnace (see Water Quality and Maintenance in your Owner’s Manual).
Adding Antifreeze to Your Central
Boiler Furnace System
Important information can be found
online if you are thinking about
adding antifreeze to your outdoor
furnace system. Topics covered
include:
• ings to know when purchasing
antifreeze
• Importance of knowing the
concentration
• Freeze protection levels
• Why you should NOT use
inhibited propylene glycol in your
Central Boiler furnace
Download the Adding Antifreeze
to Your Central Boiler Furnace
System (PDF) by visiting:
CentralBoiler.com > Explore >
Owner Resources

5
Central Boiler Outdoor Furnace Installation Guide
Fittings for Titanium Series Models
For stainless steel Titanium Series models, brass ttings are
recommended for installation of the outdoor furnace.
Shut-O Valves
Shut-o valves must be installed on each hot supply and return
water line so each line can be shut o individually for purging air from
the system. Be sure all valves and ttings are metal. Do not use plastic
valves or ttings.
Ground Rod Kit
If required, the outdoor furnace must be electrically bonded to ground
in accordance with the requirements of the authority having jurisdiction
or, in absence of such requirements, with the National Electrical Code,
ANSI/NFPA 70 and/or the Canadian Electrical Code Part 1, CSA
C22.1 Electrical Code.
Install a Ground Rod Kit (p/n 6593) and connect it to the outdoor
furnace. Refer to your Owner's Manual for more information.
Supply and Return Lines
Determine the conguration of the supply and return lines from the
outdoor furnace to where the supply and return lines will connect
to the existing heating system. Central Boiler recommends using the
ermoPEX® piping system.
ermoPEX is a fully assembled, pre-insulated piping system consisting
of two 1" Central PEX lines or two 1-1/4" PEX lines. e two lines (one
a supply and one a return line) are insulated with high-density urethane
insulation and a thick, durable, waterproof, polyethylene outer jacket.
One of the lines is marked with a black stripe for identication.
NOTE: To prevent ground water from entering the house, do not use drain tile,
PVC pipe with bubble wrap, or any other inferior material for insulating the water
lines.
NOTE: If the outdoor furnace supply and return lines are not insulated properly, or
if other brands of insulated piping are used, there can be excessive heat loss. This
heat loss can greatly increase the fuel consumption.
NOTE: If it is unavoidable that the trench will run through an area of ponding
water, use ThermoPEX instead of other materials. ThermoPEX should also be used
for above-ground or winter installations, and if the area is likely to be aected by
compaction.
ThermoPEX® Advantage
ermoPEX is exible pre-
insulated piping that is ideal for
use with outdoor wood furnaces.
ermoPEX consists of two 1-inch*
oxygen barrier Central PEX® lines
or two 1-1/4 inch** oxygen barrier
PEX lines (a supply and a return
line). e lines are insulated with
high-density urethane insulation
and a thick, durable, waterproof
polyethylene outer jacket. ermal
expansion is absorbed within the
system because the Central PEX
lines, urethane insulation and the
durable outer jacket are cast together.
e corrugated design allows exing
for easier installation. ermoPEX is
a proven product and maintenance-
free.
*CTS ASTM 1" supply and return.
**CSTS ASTM 1-1/4" supply and return.

6Central Boiler Outdoor Furnace Installation Guide
Temporary Above Ground or Winter Installations
For temporary above ground or winter installations in which the supply
and return lines can not immediately be buried underground, Central
Boiler recommends using ermoPEX. Be sure that both the insulation
and the supply and return lines will not be exposed to ultraviolet rays.
e ermoPEX black exterior jacket has UV protection but the
insulation and water lines inside do not. Use a ermoPEX termination
cap at each end of the installation to protect and seal the insulation from
water.
NOTE: Bury the ThermoPEX as soon as conditions permit (e.g., once the ground has
thawed).
NOTE: If ThermoPEX is installed temporarily above ground, provisions should be
made to prevent possible risk of re coming into contact with the ThermoPEX.
ThermoPEX is constructed of materials that can burn and transfer a re.
CAUTION
If ThermoPEX is installed temporarily above ground, do not cover with
combustible materials (e.g., straw, hay, leaves, etc.).
Digging the Trench
Before digging, be sure to call for utility locator service.
e trench depth for ermoPEX should be between 10" and 28" (25
and 71 cm).
Risks of Inferior Piping
To prevent ground water from
entering the house, do not use drain
tile, PVC pipe with bubble wrap,
or any other inferior material for
insulating the water lines.
If the outdoor furnace supply
and return lines are not insulated
properly, or if other brands of
insulated piping are used, there
can be excessive heat loss. is heat
loss can greatly increase the fuel
consumption.

7
Central Boiler Outdoor Furnace Installation Guide
Underground Electric Wire
A 14-2 (two wires plus ground) underground rated wire should supply
the outdoor furnace with electricity. A heavier gauge wire may be
needed if the run is over 200 feet (61 meters). Check local codes and
requirements. It is recommended that the incoming fuse or circuit
breaker not exceed 15 amps.
Connecting to Existing Heating System
1. Make an entrance into the building(s) where the supply and return
lines are to enter.
2. Lay the ermoPEX assembly in the trench and feed one end into
the building. Apply sealant around the supply and return lines
where they enter the building.
3. Using compressed air, purge the supply and return lines before
connecting any ttings to ensure there is no debris or foreign matter
present.
NOTE: All holes made in basement or building walls must be sealed completely to
prevent water from entering the building.
4. Close all valves on the outdoor furnace.
5. Install ttings to allow pressure-testing of both supply and return
lines. Pressurize with 50 psi (3.5 kg/cm2) of air; then check after 30
minutes to see if pressure has dropped. A drop in pressure indicates
a leak; repair as necessary.
6. Connect the supply and return lines to the outdoor furnace and to
the inside system.
NOTE: See your Owner's Manual for more information about your furnace's supply
and return line ports and connections.
CAUTION
Allow for expansion and contraction of the supply and return lines at each end.
Without an allowance for expansion and contraction, the lines may kink or the
ttings may be pulled apart, causing an immediate water loss from the outdoor
furnace. Central PEX water lines can have an expansion and contraction rate up
to .095" per each 100 ft and each 10°F (2.4 mm/30 m/5.5˚C).
7. Make sure there are no leaks in the supply and return lines; then
backll the trench.
NOTE: Do not backll the trench until the supply and return lines have been tested
to ensure there are no leaks.

8Central Boiler Outdoor Furnace Installation Guide
SYSTEM COMPONENTS
Plan with your heating system in mind
Spending time early thinking about how your outdoor furnace will tie
into your heating system can save many headaches later on. In the next
few pages, examples and illustrations are provided that show installations
with many common types of heating systems. e information provided
here is intended to be a guideline to ensure your outdoor furnace
works as it should with your system. Because every system is unique,
your actual installation will dier. If any questions arise that cannot be
answered by the information in this guide, be sure to contact your dealer
or HVAC professional.
Central Boiler provides a wide variety of components, ttings, tools and
more to accommodate your furnace's installation and connection to
your existing heating system. See your dealer for more information.
Pump Selection
When selecting a pump, it is important to correctly size it to work
properly within the system. Some factors to consider are the diameter of
the supply and return lines, total length of the supply and return lines,
equivalent length of each component installed in series, and ow rates of
the pump(s) at common equivalent lengths.
NOTE: If operating with system water at 195˚F (91˚C), it may be necessary to mount
the pumps lower.
NOTE: See the Hydronic Component Selection Guide (p/n 2482) for more detailed
information about pump selection.
e Taco 007 is a medium to high ow, low head pressure pump. In a
low-resistance system (e.g., short length of supply and return lines, only
a at plate heat exchanger, etc.), the 007 pump may need to be mounted
lower near the base of the furnace to prevent cavitation at high water
temperatures.
e Taco 009 is a medium ow, high head pressure pump that requires
an adequate amount of pressure on the outlet side to prevent the motor
from overloading.
e Taco 014 is a high ow, high head pressure pump that requires an
adequate amount of head pressure on the inlet side to prevent cavitation.
erefore, a Taco 014 may need to be mounted lower near the base of
the furnace.
Taco 009 and 014 Circulation Pumps
Taco 007 Circulation Pump
Pump Selection Example
For an installation with the furnace
200 feet from the building, 1-inch
pipes, air exchangers and and side-
arm heat exchanger, a Taco 007
pump could be selected.

9
Central Boiler Outdoor Furnace Installation Guide
Pump Installation Guidelines
e following guidelines must be adhered to when installing the
circulation pump(s).
NOTE: The direction of water ow is very important for the proper operation of
the outdoor furnace. Installing a swing check valve in the return line can prevent
possible reverse ow.
NOTE: See the Hydronic Component Selection Guide (p/n 2482) for more detailed
information.
Maximum load of the outlet on the outdoor furnace is 10A, 120VAC, and 60Hz.
• e pump motor must be installed in a horizontal position.
• e junction box must not be located below the pump motor. If
necessary, remove the four screws and rotate the pump body.
• Do not operate the circulation pump until the entire system has
been lled with water, the system has been purged, and it has
been checked for leaks or the pump may be damaged.
• Insulate the areas around the supply and return lines, pumps and
drain valve; then install and secure the back panel.
Hydronic Component Selection Guide
(p/n 2482)
An invaluable resource for selecting
the correct hydronic heating
components for your specic system.
Available from your Central Boiler
dealer.

10 Central Boiler Outdoor Furnace Installation Guide
Example of insulating around
pumps and water lines -
configurations of pumps and
water lines will vary
NOTE: At least one circulation pump must run continuously to ensure proper
operation of the outdoor furnace.
• e circulation pump(s) must be installed in the supply
line(s) with the arrow on each pump pointed away from the
outdoor furnace. In order to avoid circulation problems, do not
install the pump(s) in the return line(s).
Selecting Pump Location
• e pump(s) must be located near the base of the outdoor
furnace if the system has a high-ow pump or very low resistance
on the outlet side of the pump. For example, if the outdoor
furnace is 20 feet (6 meters) from the building and pumping
water through one-inch pipes, a 50-plate heat exchanger or
water-to-air exchanger, and back to the outdoor furnace, the
pump needs to be mounted with four feet of water above the
pump.
• e pump(s) must be located near the base of the outdoor
furnace if operating with water temperatures of 195˚F. Water at
195˚F will boil on the inlet side of the pump if there is not an
adequate amount of water above the pump. is causes reduced
ow rates, cavitation (indicated by a noisy, rattling pump) and
results in premature failure of the pump.
Example System
• 2500' elevation
• Taco 007 pump
• 50' of ermoPEX
• 40' of 1" PEX in house
• Side-arm heat exchanger on water
heater
• 125,000 Btu heat exchanger
• Flow = approximately 5 gpm
Taco 007 pump mounted with 4'
inlet head if operating at 185˚F; if
operating at 195˚F, will need 7.5'
inlet head.

11
Central Boiler Outdoor Furnace Installation Guide
• Depending on the system water temperature, four feet of water
above the pump should be adequate for systems with higher
resistance (e.g., longer loops with other ttings, elbows, heat
exchangers). For systems with low resistance (e.g., short loops,
larger diameter pipes and low resistance heat exchangers like
a water-to-air exchanger), it may be necessary to mount the
pumps with four to eight feet of water above the pump. See the
Hydronic Component Selection Guide (p/n 2482) for more
information.
• Installing the circulation pump(s) at the outdoor furnace is
recommended, but required if the building being heated is
higher than the outdoor furnace or if there is a large rise in the
water lines between the outdoor furnace and building. Hot water
boils at a lower temperature when pulled uphill (because it is at
a lower pressure); therefore, hot water must be pushed uphill to
ensure proper circulation.
NOTE: Furnace and
pump location
on furnace will vary
NOTE: Furance and
pump location
on furnace will vary

12 Central Boiler Outdoor Furnace Installation Guide
• When the pump is located in the building to be heated,
maintain a minimum of 4 feet between the water level in the
outdoor furnace and the highest point of the water line between
the furnace and the building.
4 ft. (1.2 m) min.
Pump must be installed
in the hot supply line,
before the heat exchanger,
and may be located inside
this building or on the
outdoor furnace.
Water Level Building to be heated
Ground
Level
© 2015 Central Boiler
Ports on Outdoor Furnace
Refer to the Owner's Manual for information about supply and return
ports, and for pump mounting locations on the outdoor furnace.
PEX Fittings and Tools
Central Boiler oers a wide selection of PEX ttings and tools for
designing your hydronic system. Refer to the Heating Accessories catalog
(p/n 420) or see your dealer for more information.
Push-t Fittings
Push-t Fittings are designed to simplify
pipe installation. e ttings allow you
to connect pipe in seconds with relative
ease.
• Instant push-t connection for
increased ease-of-use
• No soldering, clamps, unions or glue
required
• Lead-free
• Fit copper tubing and PEX piping
and connect in any combination

13
Central Boiler Outdoor Furnace Installation Guide
Shut-o Valves
Shut-o valves must be installed on each hot supply and return water
line so each line can be shut o individually for purging air from the
system.
• Be sure all valves and ttings are metal. Do NOT use plastic
valves or ttings.
Shut-o valves should be installed on both sides of each pump so if
it becomes necessary to repair or replace the pump, the pump can be
isolated.
Optional Thermostatic Valve
An optional thermostatic valve can be installed on each set of supply
and return lines in the system to maintain the outdoor furnace water
temperature above 150˚F (65˚C). Operating the outdoor furnace with
the water temperature less than 150˚F (65˚C) may result in more
condensation in the rebox that can lead to corrosion.
Ball Valve
Hose Bib
Hot Supply from Pump
on Outdoor Furnace
Return to
Outdoor Furnace
NOTE: Shown with valves added to allow for purging. See Filling Outdoor Furnace
and Purging Air illustration.
Optional
Thermostatic Valve
ermostatic valves can be purchased through your authorized Central
Boiler dealer.
It is recommended to set the water temperature setpoint of the furnace
to 185˚F (85˚C) to decrease the likelihood of the water temperature
falling to 150˚F (65˚C). As a result, the outdoor furnace will operate
with a greater eciency and require less maintenance.
Central Boiler Isolation Flange Kits
An excellent option for "isolating" a
circulation pump in the event repair
or replacement is necessary. Shut-o
valves also aid in purging air from
the system.

14 Central Boiler Outdoor Furnace Installation Guide
Manual Air Bleeders
Manual air bleeders may be installed in the high points of the water
lines where air may get trapped and cause circulation problems. Water
can be pumped to levels higher than the outdoor furnace as long as the
pump is pushing the water to the higher level, all air is purged from the
system, and there are no air leaks in the system. If any auto oat vents
are present in the system, they must be capped o tightly to prevent air
from entering the system.
The outdoor furnace vent cap must t loosely on the vent opening. Do not
force the cap down or try to seal it tightly onto the vent pipe. Do not extend or
restrict the vent pipe or opening. DO NOT ALLOW THE OUTDOOR FURNACE TO BE
PRESSURIZED.
Optional
Thermostatic
Valve must be
installed inside
heated building.
NOTE: See the Hydronic Component Selection Guide (p/n 2482) for more detailed
information.
Manual Air Bleeders
Often installed in high points of
water lines to "bleed o" air that
can become trapped. Trapped air in
a water line can cause circulation
problems.

15
Central Boiler Outdoor Furnace Installation Guide
CONNECTING TO EXISTING SYSTEMS
Remember, your outdoor furnace is not intended to be the only source
of heat. In the event of a prolonged power failure, a generator may be
used to prevent lines from freezing. Should the outdoor furnace be
left unattended, run out of fuel or require service, an alternate heating
source in the building being heated should be in place to prevent
damage caused by freezing.
Water Heater
DO NOT disable or remove any safety reliefs or controls. Turn o the power to
the water heater before installation.
When installing a domestic hot water heat exchanger, the hot supply line
from the outdoor furnace should be plumbed rst to the water heater
heat exchanger and then to the balance of the heating system.
H
C
M
R
NOTE
Use softened water if
water has a high mineral
content to avoid plugging
the heat exchanger.
NOTE
Installer must comply
with all applicable codes
and regulations.
NOTE
Outdoor furnace water
temperature setpoint
should be set at 185˚F
(85˚C) minimum.
NOTE
A pump must be installed
in the hot supply line
between the outdoor
furnace and thermostatic
valve.
NOTE
If outdoor furnace is not
being used for an
extended period of time
to heat water, this valve
should be closed to
prevent heat loss from
the water heater through
the side arm exchanger.
Hot Supply from Pump
on Outdoor Furnace
Return to Outdoor Furnace
Optional Thermostatic Valve
Water-to-Water
Heat Exchanger
Bypass Line
Thermostatic
Mixing Valve
This horizontal assembly
must not exceed a height
of 4 inches (10 cm) above top
of water heater.
Hot Supply
For illustration purposes
only, water heater styles
may vary.
© 2015 Central Boiler
Existing
Water
Heater
1"
Central
PEX®
Optional Bypass
Valve
(sold separately)
Many owners install a water-to-water
heat exchanger on their domestic
water heater for even more energy
savings. Central Boiler's Push-t
Fittings Water Heater Kit (p/n 9263)
makes installation quick and easy.
Water-to-water heat exchanger is sold
separately.
Central Boiler Push-t Fittings Water
Heater Kit

16 Central Boiler Outdoor Furnace Installation Guide
A manual 3-way valve may be installed so that during the non-heating
season, the water heater may be operated without operating the entire
heating system. A tempering valve (or thermostatic mixing valve) is to be
installed in the hot water outlet from the water heater. Install a tee in a
tting on the top of the water heater for the hot water heat exchanger.
NOTE: If the water heater has been in service, ush the water heater prior to
installing the hot water heat exchanger. Anode rod residue or other sediments in
the water heater may plug the heat exchanger.
CAUTION
Some gas water heaters are equipped with a high water temperature probe
that is connected to the gas valve. When the water temperature exceeds
the high limit, the gas valve enters a non-resettable lock out condition. This
requires replacement of the entire valve. The installer must determine if this
type of valve is present before installation of a water-to-water heat exchanger.
Costly maintenance may be incurred if steps are not taken during installation
to eliminate the possibility of the water temperature in the water heater
exceeding the high limit.
Existing Forced Air Installations
When the outdoor furnace is installed in conjunction with an existing
forced air system, a water-to-air heat exchanger is mounted in the
plenum or duct work of the existing furnace. Heated water from the
outdoor furnace either continuously ows through the water-to-air
heat exchanger or is diverted through a 3-way zone valve. When the
thermostat senses the need for heat, the fan on the existing furnace
forces air through the heat exchanger, transferring heat throughout the
existing ductwork.
Water Flow
For a single building water-to-air heat exchanger system with a domestic
water heater, the direction of water ow must go from the hot outlet on
the outdoor furnace to the lower side tting of the domestic water heater
exchanger, to the lower tting of the heat exchanger in the plenum of
the existing furnace, and then to the return port of the outdoor furnace.
NOTE: Some systems may have dierent ow patterns.
Items of Note in Forced Air Installations
• Plenums installed to the furnace must be constructed of metal in
accordance with NFPA 90B, 2-1.3.
Detailed Furnace Installation
Variations
Visit CentralBoiler.com to access
a library of detailed illustrations
for connecting to a wide variety of
existing heating systems and for
other heating options.