ECR International UB90-125 Instruction manual

P/N 240009432 Rev. A [03/2012]
UB90125-200SERIESII
GAS-FIRED, DIRECT VENT,
CONDENSING, HOT WATER BOILER
INSTALLATION, OPERATION &
MAINTENANCE MANUAL
An ISO 9001-2008 Certified Company
Models
UB90-125
UB90-150
UB90-175
UB90-200
Manufacturedby:
ECRInternational,Inc.
2201 Dwyer Avenue, Utica NY 13504-4729
web site: www.ecrinternational.com

2
1 - Boiler Ratings & Capacities..............................................................................................3
2 - Safe Installation And Operation .......................................................................................5
3 - Locating The Boiler ........................................................................................................6
5 - Combustion Air/ Vent Requirements...............................................................................11
6 - Combustion Air And Vent Pipe .......................................................................................13
7 - Gas Supply Piping........................................................................................................15
8 - Electrical Wiring ..........................................................................................................16
9 - Controls And Accessories..............................................................................................20
10 - Startup.....................................................................................................................22
11 - Detailed Sequence Of Operation...................................................................................27
12 - Sequence Of Operation Diagnostics..............................................................................28
13 - Checkout Procedure & Adjustments..............................................................................29
14 - Troubleshooting - High Limit Control And LWCO..............................................................31
15 - Troubleshooting.........................................................................................................33
16 - Maintenance And Cleaning ..........................................................................................42
Appendix A - Dielectric Isolation & Antifreeze Protection .....................................................44
TABLE OF CONTENTS
Safety Symbols & Warnings
The following defined symbols are used throughout this
manual to notify the reader of potential hazards of varying
risk levels.
NOTICE
Used to address practices not related to personal
injury.
CAUTION
Indicates a hazardous situation which, if not avoided,
could result in minor or moderate injury.
!
!
WARNING
Indicates a hazardous situation which, if not avoided,
could result in death or serious injury.
!
DANGER
Indicates a hazardous situation which, if not avoided,
WILL result in death or serious injury
!
IMPORTANT: Read following instructions
COMPLETELY before installing!!
KEEP THIS MANUAL NEAR BOILER
RETAIN FOR FUTURE REFERENCE
WARNING
Keep boiler area clear and free from combustible
materials, gasoline and other flammable vapors
and liquids.
DO NOT obstruct air openings to the boiler room.
Modification, substitution or elimination of factory
equipped, supplied or specified components may
result in personal injury or loss of life.
TO THE OWNER - Installation and service of this
boiler must be performed by a qualified installer.
TO THE INSTALLER - Leave all instructions with
boiler for future reference.
When this product is installed in the
Commonwealth of Massachusetts the installation
must be performed by a Licensed Plumber or
Licensed Gas Fitter.
!
WARNING
Fire, explosion, asphyxiation and electrical shock
hazard. Improper installation could result in death
or serious injury. Read this manual and understand
all requirements before beginning installation.
!

3
1 -BOILER RATINGS & CAPACITIES
- SEA LEVEL RATINGS (NATURAL AND PROPANE GASES)Table 1
Model Input
(MBH)(1) Heating Capacity (MBH)(1)(2) Net AHRI Rating (MBH)(1) Shipping Weight (lbs.) AFUE
(2) Flue Diameter
125 125 113 98 284 90.0 2” CPVC & 3” PVC
150 150 134 117 284 90.0 2” CPVC & 3” PVC
175 175 158 137 284 90.0 2” CPVC & 3” PVC
200 200 180 157 284 90.0 2” CPVC & 3” PVC
(1) 1 MBH = 1,000 Btuh (British Thermal Units Per Hour)
(2) AFUE (Annual Fuel Utilization Efficiency) and Heating Capacity is based on Department of Energy test procedure.
- Boiler JacketsFigure 1
These low pressure gas-fired hot water boilers are design certified by CSA International, for use with natural and propane
gases. Boilers are constructed and hydrostatically tested for maximum working pressure of 50 psi (pounds per square
inch) in accordance with A.S.M.E. (American Society of Mechanical Engineers) Boiler and Pressure Vessel Code, Section IV
Standards for heating boilers.
Boilers are certified in accordance with ANSI (American National Standards Institute) Z21.13 standards as gas-fired, direct
vent, condensing, hot water boilers.
Heating Capacity indicates amount of heat available after subtracting losses up the stack. Most of this heat is available
to heat water. Small portion is heat loss from jacket and surfaces of boiler, it is assumed this heat stays in the structure.
Net AHRI Rating represents portion of remaining heat applied to heat radiation or terminal units (i.e. Finned tube
baseboard, cast iron radiators, radiant floor, etc.). Difference between Heating Capacity and Net AHRI Rating, called piping
and pickup allowance, establishes reserve for heating volume of water in the system and offsetting heat losses from
piping. Net AHRI Ratings shown are based on piping and pickup factor of 1.15. Net AHRI Rating of boiler selected should
be greater than or equal to calculated peak heating load (heat loss) for building or area(s) served by boiler and associated
hot water heating systems. Manufacturer should be consulted before selecting boiler for installations having unusual
piping and pickup requirements.

4
1 - BOILER RATINGS & CAPACITIES
This is gas-fired direct vent cast aluminum hot water boiler. Cast aluminum heat exchanger means better heat transfer
and thermal storage than similarly sized cast iron boilers, which results in higher efficiency. Heating system water
absorbs large amounts of heat from cast aluminum heat exchanger, cooling flue gases and causing condensation. Sealed
combustion, premix gas burner, and low flame temperature means drastically reduced CO and NOx emissions, which
contribute to cleaner and healthier environment.
Appliance, unlike normal residential atmospheric and induced draft units, takes its combustion air directly from outdoors
(sealed combustion) and does not compete with building occupants for fresh air. Sealed combustion (also known as “direct
vent”) is safest and best way to obtain plenty of clean combustion air. Forced draft fan draws in outside combustion air to
mix with gas, which flows into pre-mix burner and combusts. Fan forces resulting flue gases from boiler unit and provides
positive removal of flue gases from building through PVC and CPVC vent pipes.
- LP GASTable 3
Nominal
Input 200,000 175,000 150,000 125,000
Vent Lengths Vent Lengths Vent Lengths Vent Lengths
Altitude Min. Max Min. Max Min. Max Min. Max
0 200,000 200,000 175,000 175,000 150,000 150,000 125,000 125,000
1,000 195,900 195,750 171,900 171,200 146,900 146,700 123,050 122,250
2,000 191,800 191,500 168,800 167,400 143,800 143,400 121,100 119,500
3,000 187,700 187,250 165,700 163,600 140,700 140,100 119,150 116,750
4,000 183,600 183,000 162,600 159,800 137,600 136,800 117,200 114,000
5,000 179,500 178,750 159,500 156,000 134,500 133,500 115,250 111,250
6,000 175,400 174,500 156,400 152,200 131,400 130,200 113,300 108,500
7,000 171,300 170,250 153,300 148,400 128,300 126,900 111,350 105,750
8,000 167,200 166,000 150,200 144,600 125,200 123,600 109,400 103,000
9,000 163,100 161,750 147,100 140,800 122,100 120,300 107,450 100,250
10,000 159,000 157,500 144,000 137,000 119,000 117,000 105,500 97,500
- NATURAL GASTable 2
Nominal
Input 200,000 175,000 150,000 125,000
Vent Lengths Vent Lengths Vent Lengths Vent Lengths
Altitude Min Max Min. Max Min. Max Min. Max
0 200,000 200,000 175,000 175,000 150,000 150,000 125,000 125,000
1,000 197,000 196,500 172,400 172,200 147,800 147,400 123,500 123,000
2,000 194,000 193,000 169,800 169,400 145,600 144,800 122,000 121,000
3,000 191,000 189,500 167,200 166,600 143,400 142,200 120,500 119,000
4,000 188,000 186,000 164,600 163,800 141,200 139,600 119,000 117,000
5,000 185,000 182,500 162,000 161,000 139,000 137,000 117,500 115,000
6,000 182,000 179,000 159,400 158,200 136,800 134,400 116,000 113,000
7,000 179,000 175,500 156,800 155,400 134,600 131,800 114,500 111,000
8,000 176,000 172,000 154,200 152,600 132,400 129,200 113,000 109,000
9,000 173,000 168,500 151,600 149,800 130,200 126,600 111,500 107,000
10,000 170,000 165,000 149,000 147,000 128,000 124,000 110,000 105,000
Ratings shown are for sea level applications. Boiler automatically derates input as altitude
increases. No alterations to boiler are required for altitudes above sea level.

5
Boiler is equipped for residential installations. If used for
commercial applications; additional code requirements
must be adhered to. This may require additional controls,
including but not limited to manual reset low water cut off,
manual reset high temperature limit, and wiring and/or
piping modifications.
Installation must conform to the requirements of the 1.
authority having jurisdiction or, in the absence of such
requirements, to the National Fuel Gas Code, ANSI
Z223.1/NFPA 54.
Where required by authority having jurisdiction, 2.
installation must conform to the Standard for Controls
and Safety Devices for Automatically fired Boilers,
ANSI/ASME CSD-1.
Be certain gas input rate is correct. Over-firing may 3.
result in early failure of boiler components; this may
cause dangerous operation. Under-firing may result in
too much air for pre-mix burner causing poor or loss of
combustion.
Never vent products of combustion from this boiler to 4.
enclosed space. Always vent to outdoors. Never vent to
another room or to inside building.
Verify adequate outdoor air supply to boiler for 5.
complete combustion.
Follow regular service and maintenance schedule for 6.
efficient and safe operation.
Keep boiler area clean of debris and free from 7.
combustible materials, gasoline and other flammable
vapors and liquids.
Proper through-the-wall or through-the-roof 8.
combustion venting shall be in accordance with
materials and methods described in this manual.
Installation must comply with local codes.
Boiler and related hot water heating systems are
9.
not do-it-yourself items. Installation and service by
qualified professionals are required.
2 - SAFE INSTALLATION AND OPERATION
Installers -Follow local regulations with respect to
installation of CO (Carbon Monoxide) Detectors. Follow
maintenance recommendations in this manual. See
“Maintenance And Cleaning” on page 42.
Boiler Sizing
Verify you have selected the boiler with proper capacity• before continuing installation. AHRI Rating of boiler
selected should be greater than or equal to calculated
peak heating load (heat loss) for building or area(s) served
by boiler and associated hot water heating systems. See
“Boiler Ratings & Capacities” on page 3.
Heat loss calculations should be based on approved• industry methods.
Considerations For Boiler Location
Before selecting boiler location, consider following.
Supplied with correct type of gas (natural gas or• propane).
Connected to suitable combustion air intake piping• system to supply correct amount of fresh (outdoor) air
for combustion. See “Combustion Air And Vent Pipe” on
page 13.
Connected to suitable venting system to remove• hazardous products of gas combustion. See “Combustion
Air And Vent Pipe” on page 13.
Connected to suitable hot water heating system.•
Supplied with suitable electrical supply for all boiler• motors and controls.
Connected to properly located thermostat or operating• control. (Not included with boiler)
WARNING
Fire hazard. Do not install boiler on carpeting.
Failure to follow these instructions could result in
death or serious injury.
!
Placed on level surface (DO NOT install on carpeting)•
Condensate drain line must be pitched down to floor• drain or external condensate pump with reservoir at ¼”
per foot (21 mm/m) (wood frame or blocks may be used
to raise boiler).
WARNING
Improper installation, adjustment, alteration, service
or maintenance could result in death or serious
injury.
!

6
Locating The Boiler
Select level location, central to piping systems served 1.
and close to vent and air intake terminals as possible.
Accessibility clearances, if more stringent (i.e. larger
2.
clearances) than required fire protection clearances,
must be used for boiler installation. Accessibility
clearances may be achieved with use of removable
walls or partitions.
Clearances shown in Table 4 indicate required 3.
clearances per CSA listing. Minimum 1” (25 mm)
clearance must be maintained between combustible
construction and each of the right, top and back
surfaces of boiler. Minimum 8” (203 mm) clearance is
required on left side, to allow room for inlet air pipe.
18” (457 mm) clearance must be maintained at front
where passage is required for cleaning or servicing,
inspection or replacement of any parts that normally
require such attention. Allow 24” (610 mm) at front
and left side and 8” (203 mm) at top for servicing.
No combustible clearances are required to venting or
combustion air intake piping.
- BOILER CLEARANCESTable 4
Unit Combustible
Clearance Accessibility, Cleaning, and Servicing
Top 1” (25 mm) 8” (203 mm)
Left Side 8” (203 mm) 24” (610 mm)
Right Side 1” (25 mm) -
Base 1” (25 mm) -
Front 0” (0 mm) 24” (610 mm)
Back 1” (25 mm) -
Intake/Vent
Piping 0” (0 mm) -
Near Boiler Hot
Water Piping 1” (25 mm) -
All distances measured from boiler cabinet.
Keep boiler area clean of debris and free of flammable 4.
and combustible materials, liquids and vapors.
Install equipment in location which facilitates operation
5.
of venting and combustion air intake piping systems as
described in this manual.
Advise owner to keep venting and combustion air 6.
intake passages free of obstructions. Both venting
and combustion air intake piping systems connected
to outdoors must permit flow through piping systems
without restrictions for boiler to operate.
Boiler shall be installed such that automatic gas
7.
ignition system components are protected from water
(dripping, spraying, rain, etc.) during operation and
service (circulator replacement, condensate trap,
control replacement, etc.).
Boiler must be located where ambient temperatures
8.
(minimum possible room temperatures where boiler
is installed assuming boiler is not in operation and
therefore contributes no heat to space) are always
at or above 32°F (0°C) to prevent freezing of liquid
condensate.
If boiler is not level condensate drain lines will not 9.
function properly. Adjustable feet are located on boiler
to make up for minor surface irregularities or tilt.
Wood frame or blocks may be used to raise boiler 10.
to maintain drain pitch or to be above external
condensate pump reservoir.
3 - LOCATING THE BOILER
Removal Of Existing Boiler From Common Vent
System
When an existing boiler is removed from a common
venting system, the common venting system is likely to be
too large for proper venting of the appliances remaining
connected to it. At the time of removal of an existing boiler,
the following steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances remaining
connected to the common venting system are not in
operation.
Seal any unused openings in the common venting 1.
system.
Visually inspect the venting system for proper size and 2.
horizontal pitch and determine there is no blockage
or restriction, leakage, corrosion or other deficiencies
which could cause an unsafe condition.
In so far as is practical, close all building doors and 3.
windows and all doors between the space in which the
appliances remaining connected to the common venting
system are located and other spaces of the building.
Turn on clothes dryer and any appliance not connected
to the common venting system. Turn on any exhaust
fans, such as range hoods and bathroom exhaust, so
they will operate at maximum speed. Do not operate a
summer exhaust fan. Close fire dampers.
Place in operation appliance being inspected. Follow 4.
lighting instructions. Adjust thermostat so appliances
operate continuously.
Test for spillage at draft hood relief opening after 5 5.
minutes of main burner operation. Use flame of match
or candle, or smoke from cigarette, cigar or pipe.

7
After it has been determined each appliance remaining 6.
connected to common venting system properly vents
when tested as outlined above, return doors, windows,
exhaust fans and any other gas-burning appliance to
their previous condition.
Any improper operation of common venting system
7.
should be corrected so installation conforms with the
National Fuel Code, ANSI Z223.1/NFPA 54. When
resizing any portion of common venting system,
common venting system should be resized to approach
minimum size as determined using appropriate tables
in chapter 13 of the National Fuel Code, ANSI Z223.1/
NFPA 54.
Placing The Boiler
Place boiler to provide most direct connections to• combustion air, vent, and system piping as possible.
Place crated boiler as close to selected location as• possible and uncrate boiler.
Move uncrated boiler into position with appliance dolly• or 2-wheel hand truck.
Insert dolly or hand truck under• right hand side of
boiler. It is possible to slide boiler for short distance on
smooth floor or surface.
3 - LOCATING THE BOILER

8
Do not install copper supply and return piping directly 1.
into aluminum boiler section castings due to galvanic
corrosion between dissimilar metals.
Use iron, steel bushings or pipe connectors between 2.
copper system piping and boiler to make final
connection to boiler.
Use of dielectric unions is acceptable, installer supplied. 3.
Packaged boiler is furnished with iron piping in front 4.
boiler section for supply and return connections.
Install all of radiation units (panels, radiators, 5.
baseboard, or tubing) and supply and return mains
first, when installation of boiler is for new heating
system.
After installation of all heating system piping and 6.
components; make final connection of system piping to
boiler.
Hot water boiler installed above radiation level or 7.
as required by authority having jurisdiction must be
equipped with low water cut off device (included with
boiler).
Periodic inspection is necessary, as is flushing of float 8.
type devices, per low water cut off manufacturers
specific instructions.
Expansion Tank And Make-Up Water
Determine required system fill pressure, design• temperature, and water content.
Boiler contains 2.6 gallons (U.S.). Size expansion tank• accordingly. Consult expansion tank manufacturer for
proper sizing information.
Connect properly sized expansion tank (not furnished)• See Figure 2, for diaphragm type expansion tank.
For diaphragm type expansion tanks, adjust tank air
pressure to match system fill pressure.
Install air vent (furnished) as shown for diaphragm type• expansion tank system only.
Install make-up water connections as shown and per• local codes.
If pressure reducing valve is used, adjust to match• system fill pressure. Verify clean water supply is
available when connecting cold make-up water supply
to boiler. When water supply is from well or pump,
install sand strainer at pump.
4 - NEAR BOILER PIPING
- Diaphragm Type Expansion TankFigure 2 Piping
- Relief Valve Discharge PipingFigure 3
WARNING
Burn and scald hazard. Safety relief valve could
discharge steam or hot water during operation.
Install discharge piping per these instructions.
!
Check local codes
for maximum
distance from
floor or other
allowable safe
point of discharge
RELIEF VALVE
DISCHARGE
PIPING

9
Safety Relief Valve / Temperature Pressure Gauge
Boiler is furnished with safety relief valve and temperature
pressure gauge.
Install safety relief valve using pipe fittings provided• with boiler. Figure 3, Page 8.
Install safety relief valve with spindle in vertical position.• Do not install shutoff valve between boiler and safety• relief valve.
Install discharge piping from safety relief valve.• Use ¾” or larger pipe.A. Use pipe suitable for temperatures of 375°FB. (191°C) or greater.
Individual boiler discharge piping shall beC. independent of other discharge piping.
Size and arrange discharge piping to avoidD. reducing safety relief valve relieving capacity below
minimum relief valve capacity stated on rating
plate.
Run pipe as short and straight as possible toE. location protecting user from scalding and properly
drain piping.
Install union, if used, close to safety relief valveF. outlet.
Install elbow(s), if used, close to safety relief valveG. outlet and downstream of union (if used).
Terminate pipe with plain end (not threaded).H.
NOTE: When zoning with
circulators, use furnished
circulator pump as one of
zone pumps. Tape or wire
nut each stripped end of
electrical wire for circulator
pump inside junction box
to prevent short circuits.
Unplug circulator pump
wiring at integrated boiler
control.
Supply And Return Lines
Packaged boiler receives 1¼” NPT supply and return piping
from top access.
4 - NEAR BOILER PIPING
- Single Zone Boiler PipingFigure 4
- Multi Zone Boiler Piping With ZoneFigure 5 Valves
- Multi-zone Boiler Piping withFigure 6 Circulators

10
Condensate Drain Requirements
Pitch condensate drain line down to floor drain
at minimum of ¼” per foot (21mm/m). External
condensate pump (not furnished) may be used if
floor drain is not available. Condensate pump must be
designed for flue gas condensate application.
Condensate trap is proved with boiler.
Build condensate trap in the field. See Figure 7.
1.
Wood frame or blocks may be used to raise boiler 2.
to maintain drain pitch or to be above external
condensate pump reservoir.
115 volt AC receptacle provided on service switch 3.
junction box which is located at boiler right side,
to provide power for external condensate pump (if
needed).
Condensate Drain Piping
Condensate trap is to be field installed as shown in•
Figure 7.
Provided are ½” PVC fittings for condensate drain• trap (assembled in field).
The ½” diameter schedule 40 PVC condensate• drain piping and pipe fittings must conform to ANSI
standards and ASTM D1785 or D2846.
Schedule 40 PVC cement and primer must conform• to ASTM D2564 or F493. In Canada, use CSA or ULC
certified schedule 40 PVC drain pipe and cement.
Condensate pump with reservoir (not furnished) may• be used to remove condensate to drain line (sanitary
line) above boiler if floor drain is not available or is
inaccessible
Filling Condensate Trap With Water
Manually fill condensate trap at initial start up with water.
Following steps are required to fill condensate trap for
start up. Steps are only required at initial start up or if
maintenance requires draining of condensate trap:
Pour about 1 cup of cold tap water into condensate trap 1.
vent.
Excess water will go through condensate drain line. 2.
Verify proper operation of drain line (and external
condensate pump if used).
Chilled Water Piping
Install boiler used in connection with refrigeration system,
so chiller medium is piped in parallel with boiler with
appropriate valves to prevent chilled medium from entering
boiler.
Boiler piping system of hot water boiler connected to
heating coils located in air handling units where they may
be exposed to refrigerated air circulation must be equipped
with flow control valves or other automatic means to
prevent gravity circulation of boiler water during cooling
cycle.
4 - NEAR BOILER PIPING
- Condensate Trap and VentFigure 7
To Exhaust Vent
(2” CPVC)
½” Adapter
Male NPT x Socket
Weld PVC Piping
1 3/8” Long
To Boiler Flue Outlet (2” CPVC)
2” Unthreaded Male x 2” NPT Male PVC Bushing
1/2” Unthreaded PVC Elbow
1/2” Unthreaded PVC Piping 3 3/4” Long
1/2” Unthreaded PVC Elbow
1/2” Unthreaded PVC Piping 2” Long
1/2” Unthreaded PVC Piping 3 3/4” Long
1/2” Unthreaded PVC Tee
To Condensate Drain (Field Supplied)
2” NPT Male PVC Bushing
1/2” Unthreaded PVC Piping 12” Long