GWH 425 PN
Applications manual
For tankless and point of use water heaters
|
2
Table of Contents
1 Introduction 3
2 Bosch Water Heating Models 3
2.1 Sizing tankless water heaters 4
2.2 Bosch GWH 715 ES 6
2.3 Bosch GWH C 800 ES 7
2.4 Outdoor Installation for GWH 715 ES and GWH C 800 ES 8
2.5 Bosch GWH 345 ESR 9
2.6 Bosch GWH 450 ESR 10
2.7 Bosch GWH 425 EF 11
2.8 Bosch GWH 425 HN 12
2.9 Bosch GWH 425 PN 13
2.10 Bosch GWH 260 PN 14
2.11 Powerstream Pro RP17PT, RP27PT 15
2.12 Powerstream Pro RP1P, RP2P, RP3P, RP7P, RP9P, RP12PT 16
2.13 Ariston Pro GL2.5Ti, GL4Ti, GL8Ti 17
3 Domestic Water Heating Applications 18
Applications manual
3.1 Point-of-use applications 18
3.2 Whole house applications 22
4 High Volume Potable Water Heating 26
4.1 Parallel unit applications 26
4.2 Cascade unit applications 28
4.3 External storage tank loading applications 29
5 Open Loop Space Heating 32
5.1 External storage tank 32
5.2 Indirect tank applications 42
6 Maintenance Drawings 44
6.1 Descaling procedure 44
6.1 Descaling procedure diagram 45
Application manual | 11.2007
Bosch Water Heating
Applications manual
1 Introduction
The Bosch Applications Manual is intended to present some of the
most common applications of the Bosch line of tankless and point of
use water heaters. Application drawings are shown with both piping
and corresponding electrical schematics where applicable. Auxiliary
equipment depicted does not necessarily represent any one manufacturer or specifi c model number. There are a wide variety of
techniques, practices and piping strategies possible when installing
water heating appliances. It is the responsibility of the installing
contractor to determine the most suitable arrangement for the
application.
Although this manual covers many common applications for our
products, system possibilities are virtually endless. Should you
encounter an application that is not covered in this manual or have
any questions regarding any of its content, we encourage you to
contact your local sales representative or us directly at Bosch Water
Heating.
This is not a substitute for any of the product’s installation manuals.
All specifi cations subject to change.
Installation must conform with local codes or, in the absence of
local codes, the National Fuel Gas Code ANSI Z 223.1/NFPA 54.
In Canada: Installation must conform with CGA B149.(1,2) INSTALLATION CODES and/or local installation codes.
| 3
2 Bosch Water Heating Models
This section describes the water heaters available from Bosch Water
Heating. The information given in each section provides a general
overview to the specifi cations of that particular model. More detai-
led information is contained in the installation manuals. Download
these manuals at www.BoschPro.com.
Applications manual | 11.2007Bosch Water Heating
|
4
2.1 Sizing tankless water heaters
Defi nitions
Major applications (2 GPM or more): Washing machine, bath tub,
shower nozzle
Minor applications(1.5 GPM or less): Low fl ow shower head,
bathroom sink, kitchen sink
Rule of thumb sizing
The tables below provide a general rule of thumb when sizing for
most residential applications. For commercial applications or for a
more detailed sizing method, use the instructions below in conjunction with the charts on the next page.
Sizing by Chart
Measure the fl ow rates at each fi xture that will be used simultane-
ously and add them together. If only one application will be used
at a time measure each fi xture and use the maximum fl ow rate
observed.
Rule of Thumb Sizing
Model Number Number of Major
Applications
Number of Minor
Applications
Applications manual
GWH 715 ES 2 0
GWH C 800 ES 2 1
GWH 425 HN/PN/EF 1 1
GWH 425 HN/PN/EF 0 2
GWH 260 PN 1 0
RP17PT 1 0
RP27PT 1 1
Using a known volume container, record several fi ll times. Per-
form the calculation below to determine the fl ow rate (a one
gallon fi ll time of 30 seconds is 2.0 gallons per minute (GPM):
Flow rate (GPM) =
Volume (gallons)
Fill time (sec)
Using a thermometer, measure the incoming water temperature.
Subtract this temperature from the desired hot water temperature
to get the degree rise. So, if the desired hot water temperature is
120F and incoming temperature is 55F, the desired degree rise is
65F.
This example requires a fl ow rate of 2.0 GPM at a 65˚F rise. The
data point is shown on each graph. Since the demand is above
the GWH 260 PN capacity, this application would require a GWH
425 HN/PN/EF gas tankless water heater. The electrical model
used for this application would be the RP27PT electric tankless
water heater.
sec
x
60
min
Application manual | 11.2007
Bosch Water Heating
Applications manual
GWH 425 PN/HN
GWH 260 PN/HN
t
C
0
5
0
5
0
5
0
5
0
e
M
P
Note
s
GPM
8
7
6
5
4
3
2
1
| 5
0
10 20 30 40 50 60 70 80 90
Degree rise (°F)
as Appliance Sizing Char
P
4.
.
.
.
.
1.
1.
P7
.
.
10 20 30 40 50 60 70 80 90
ectric Appliance Sizing Chart
: Maximum flow rates dependant on site condition
Degree ris
Applications manual | 11.2007Bosch Water Heating
|
6
2.2 Bosch GWH 715 ES
Applications manual
Features:
Electronic ignition and built in power vent
82% thermal effi ciency
Vents vertically or horizontally with 3" or 4" stainless steel (AL29-
4C)
Direct vent room-sealed combustion
Computerized temperature control — ensures temperature stability
Model GWH 715 ES N for natural gas (NG) supply
Model GWH 715 ES L for liquid propane (LP) supply
15-year warranty
Qualifi es for $300 tax credit
GWH 715 ES Technical Specifi cations
Gas input Natural Gas: 19,900 - 199,000 BTU
LP Gas: 19,900 - 199,000 BTU
Minimum fl ow to activate 0.65 gallons per minute (gpm)
Flow rates 45˚F rise @ 7.2 gpm
55˚F rise @ 5.9 gpm
65˚F rise @ 5.0 gpm
77˚F rise @ 4.2 gpm
90˚F rise @ 3.6 gpm
Thermal Effi ciency NG: 82% LP: 82%
Dimensions 30½" h x 17⅞" w x 11¼" d
Weight 67 lbs.
Modulating gas valve yes
Ignition Electronic
Accessories Outdoor kit (PTOK)
Wireless Remote (TSTAT2)
Tankless Link Cascading Kit (TLINK)
Freeze Prevention Kit (8700400022)
Water Filter Kit (8703305356)
GWH 715 ES Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 4" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 9" W.C.
Maximum: 14" W.C.
Water pressure
(Static)
Minimum: 30 PSI
Minimum well pressure: 40 PSI
Maximum: 150 PSI
Electrical supply 120VAC - plugs in
Venting 3" or 4" stainless steel (AL29-4C)
direct vent
room-sealed combustion
GWH 715 ES Installation Clearances
Top (A) 12"
Front (B) 1"
Back 0"
Sides 1"
Floor (C) 12"
3ft minimum
distance
3ft minimum
distance
Fig. 1 Venting confi gurations
Installation guidelines:
Venting:
Must be 3" or 4" AL29-4C sealed stainless steel vent pipe.
Slope horizontal runs up to termination ¼" per foot. The last
horizontal section of exhaust vent pipe between last elbow and
termination must slope down to the termination ¼" per foot.
Do not combination vent with any other appliance.
Install condensate drain where applicable.
See manual for vent terminator clearances.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use unions to facilitate easy future maintenance.
Use full port ball valves for isolation valves.
Partially fi ll condensate drain tube loop (where applicable) with
water prior to start up.
Application manual | 11.2007
Bosch Water Heating
Applications manual
2.3 Bosch GWH C 800 ES
Features:
Electronic ignition and built in power vent
Condensing technology with 92% thermal effi ciency
Vents vertically or horizontally with 3" or 4" PVC, CPVC or ABS
(Schedule 40) vent pipe.
Direct vent room-sealed combustion with concentric venting
option
Computerized temperature control — ensures temperature stability
Model GWH C 800 ES N for natural gas (NG) supply
Model GWH C 800 ES L for liquid propane (LP) supply
15-year warranty
Qualifi es for $300 tax credit
GWH C 800 ES Technical Specifi cations
Gas input Natural Gas: 19,900 - 199,000 BTU
LP Gas: 19,900 - 199,000 BTU
Minimum fl ow to activate 0.65 gallons per minute (gpm)
Flow rates 45˚F rise @ 8.0 gpm
55˚F rise @ 6.4 gpm
65˚F rise @ 5.5 gpm
77˚F rise @ 4.6 gpm
90˚F rise @ 3.9 gpm
Thermal Effi ciency NG: 92% LP: 92%
Dimensions 30½" h x 17⅞" w x 11¼" d
Weight 74 lbs.
Modulating gas valve yes
Ignition Electronic
Accessories Outdoor kit (PTOK)
Wireless Remote (TSTAT2)
Tankless Link Cascading Kit (TLINK)
Freeze Prevention Kit (8700400022)
Water Filter Kit (8703305356)
Concentic Termination Kit
(BWH60L46)
GWH C 800 ES Installation Clearances
Top (A) 12"
Front (B) 1"
Back 0"
Sides 1"
Floor (C) 12"
MAINTAIN 12 IN.
(1
8 IN. FOR CANADA)
MINIMUM CLEARANCE
ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL.
MAXIMUM OF 24 IN.
ABOVE ROOF.
INTAKE
Fig. 1 Venting confi gurations
VENT
DRAIN TEE
COMBUSTION
AIR
ROOF BOOT/
FLASHING (FIELD
SUPPLIED
EXHAUST
INTAKE
EXHAUST
DRAIN TEE
| 7
MINIMUM
VENT
COMBUSTION
1”
AIR
GWH C 800 ES Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 4" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 9" W.C.
Maximum: 14" W.C.
Water pressure
(Static)
Minimum: 30 PSI
Minimum well pressure: 40 PSI
Maximum: 150 PSI
Electrical supply 120VAC - plugs in
Venting 3" or 4" PVC, CPVC, or ABS
(Schedule 40) direct vent sealed
combustion
Installation guidelines:
Venting:
Must be 3" or 4" PVC, CPVC or ABS (Schedule 40) vent pipe.
Attach drain for internal condensate siphon and dispose of
according to local codes.
Do not combination vent with any other appliance.
Install an external condensate drain where applicable.
See manual for vent terminator clearances.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use unions to facilitate easy future maintenance.
Use full port ball valves for isolation valves.
Partially fi ll condensate drain tube loop (where applicable)
Applications manual | 11.2007Bosch Water Heating
8
|
Applications manual
2.4 Outdoor Installation for GWH 715 ES,
and GWH C 800 ES
Outdoor Kit (PTOK) installation:
The installation of this outdoor kit (PTOK) is required when
installing either of the above appliances outdoors
Outdoor cap easily retrofi ts to these indoor models
Outdoor kit comes with Freeze Prevention which must be installed
Exterior water piping should be protected if freezing conditions
could exist
Minimum clearances:
Installation on wood siding
Ref. Description
A
Directly below or adjacent to
an opening; operable
B
windows, doors and any fresh
air openings
C
D From any adjacent wall ≥ 4 ft
Below a gutter, sanitary
E
pipework, eaves or overhang
F Above ground ≥ 1 ft
From a gas meter or gas
G
regulator
Outdoor Installation Clearances
Source: NFPA 54 National Fuel Gas Code
ANSI Z223.1
Installation on vinyl siding:
Min.
distances
≥ 4 ft
≥ 3 ft
≥ 5 ft
Application manual | 11.2007
Bosch Water Heating
Applications manual
2.6 Bosch GWH 345 ESR
Features:
Specifi cally designed for recirculating applications
Electronic ignition and built in power vent
GWH 345 ESR thermal effi ciency of 82%
Vents vertically or horizontally with 3" stainless steel (AL29-4C)
Direct vent room-sealed combustion
Computerized temperature control — ensures temperature
stability
Model GWH 345 ESR N for natural gas (NG) supply
Model GWH 345 ESR L for liquid propane (LP) supply
10-year warranty
GWH 345 ESR Technical Specifi cations
Gas input GWH 345 ESR: 32,000 - 95,000 Btu/h
Maximum fl ow rates GWH 345 ESR: 3.5gpm @ 45°F rise
Thermal Effi ciency 82%
Dimensions 27.5" h x 15.75" w x 11.75" d
Weight 47 lbs.
Modulating gas valve yes
Ignition Electronic
GWH 345 ESR Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 5.5" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 11" W.C.
Maximum: 14" W.C.
Electrical supply 120VAC - plugs in
Venting 3" stainless steel (AL29-4C)
direct vent
room-sealed combustion
GWH 450 ESR Installation Clearances
Top (A) 12"
Front (B) 1"
Back 0"
Sides 1"
Floor (C) 12"
| 9
Fig. 1 Venting confi gurations
Installation guidelines:
Venting:
Must be 3" or 4" AL29-4C sealed stainless steel vent pipe.
Slope horizontal runs up to termination ¼" per foot. The horizon-
tal section between last elbow and termination must slope down
to the termination ¼" per foot.
Do not combination vent with any other appliance.
Always install an external condensate drain except when termi-
nating horizontally with less than 3 feet of pipe.
See manual for vent terminator clearances.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use unions to facilitate easy future maintenance.
Use full port ball valves for isolation valves.
Partially fi ll condensate drain tube loop with water prior to start
up.
Applications manual | 11.2007Bosch Water Heating
|
10
2.6 Bosch GWH 450 ESR
Features:
Specifi cally designed for recirculating applications
Electronic ignition and built in power vent
GWH 450 ESR thermal effi ciency of 81%
Vents vertically or horizontally with 3" stainless steel (AL29-4C)
Direct vent room-sealed combustion
Computerized temperature control — ensures temperature
stability
Model GWH 450 ESR N for natural gas (NG) supply
Model GWH 450 ESR L for liquid propane (LP) supply
10-year warranty
GWH 450 ESR Technical Specifi cations
Gas input GWH 450 ESR: 45,000 - 120,000 Btu/h
Maximum fl ow rates GWH 450 ESR: 4.5gpm @ 45°F rise
Thermal Effi ciency 81%
Dimensions 27.5" h x 15.75" w x 11.75" d
Weight 47 lbs.
Modulating gas valve yes
Ignition Electronic
GWH 450 ESR Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 5.5" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 11" W.C.
Maximum: 14" W.C.
Electrical supply 120VAC - plugs in
Venting 3" stainless steel (AL29-4C)
direct vent
room-sealed combustion
GWH 450 ESR Installation Clearances
Top (A) 12"
Front (B) 1"
Back 0"
Sides 1"
Floor (C) 12"
Applications manual
Fig. 1 Venting confi gurations
Installation guidelines:
Venting:
Must be 3" or 4" AL29-4C sealed stainless steel vent pipe.
Slope horizontal runs up to termination ¼" per foot. The horizon-
tal section between last elbow and termination must slope down
to the termination ¼" per foot.
Do not combination vent with any other appliance.
Always install an external condensate drain except when termi-
nating horizontally with less than 3 feet of pipe.
See manual for vent terminator clearances.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use unions to facilitate easy future maintenance.
Use full port ball valves for isolation valves.
Partially fi ll condensate drain tube loop with water prior to start
up.
Application manual | 11.2007
Bosch Water Heating
Applications manual
2.7 Bosch GWH 425 EF
Features:
Electronic ignition and built in power vent
Thermal effi ciency of 82%
Vents with 4" stainless steel or galvanized vent pipe
Specifically designed for horizontal vent terminations
Modulating gas valve — ensures temperature
stability
Model GWH 425 EF N for natural gas (NG) supply
Model GWH 425 EF L for liquid propane (LP) supply
15-year warranty
Qualifi es for $300 tax credit (LP only)
GWH 425 EF Technical Specifi cations
Gas input Natural Gas: 28,000 - 130,000 Btu/h
LP Gas: 28,000- 125,000 Btu/h
Minimum fl ow to
activate
Maximum fl ow rates 4.6 gpm @ 45°F rise
Thermal Effi ciency NG: 80% LP: 82%
Dimensions 29.75" h x 18.25" w x 8.75" d
Weight 44 lbs.
Modulating gas valve yes
Ignition Electronic
GWH 425 EF Installation Specifi cations
Gas connection ½" Male NPT
Water connections ½" Male NPT
NG gas pressure Minimum: 7" W.C.
LP gas pressure Minimum: 11" W.C.
Electrical supply 120VAC - plugs in
GWH 425 EF Installation Clearances
Top (A) 12"
Front (B) 4"
Back 0"
Sides 4"
Floor (C) 12"
0.5 gallons per minute (GPM)
Maximum: 14" W.C.
Maximum: 14" W.C.
Venting 4" stainless steel (AL29-4C)
or 26 gauge galvanized
| 11
Fig. 1 Venting confi gurations
Installation guidelines:
Venting:
4" AL29-4C sealed stainless steel or 26 gauge galvanized vent
pipe.
Slope horizontal runs up to termination ¼" per foot.
Do not combination vent with any other appliance.
See manual for vent terminator clearances.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ½".
Do not solder directly to connections on the bottom of the unit.
Use full port ball valves for isolation valves.
Applications manual | 11.2007Bosch Water Heating
|
12
2.8 Bosch GWH 425 HN
Features:
Hydro-generated ignition
80% thermal effi ciency
Endless hot water for one major application at a time
Venting: 5" double wall B-vent — natural draft
Modulating gas valve — constant temperature at varying flow rates
Model GWH 425 HN N for natural gas (NG) supply
Model GWH 425 HN L for liquid propane (LP) supply
15-year warranty
Qualifi es for $300 tax credit
GWH 425 HN Technical Specifi cations
Gas input Natural Gas: 30,735 - 117,000 BTU
LP Gas: 30,735 - 117,000 BTU
Minimum fl ow to activate 0.6 gallons per minute (gpm)
Flow rates 45˚F rise @ 4.2 gpm
55˚F rise @ 3.4 gpm
65˚F rise @ 2.9 gpm
77˚F rise @ 2.4 gpm
90˚F rise @ 2.1 gpm
Thermal Effi ciency NG: 80% LP: 80%
Dimensions 25.75" h x 16.75" w x 8.5" d
Weight 33 lbs.
Modulating gas valve yes
Ignition Hydro-generated
Accessories Horizontal vent kit (AQ4) - power
vent kit for horizontal venting
GWH 425 HN Installation Clearances
Top (A) 12"
Front (B) 4"
Back 0"
Sides 4"
Floor (C) 12"
LISTED GAS VENT
ESTABLISH A ONE
FOOT RISE BEFORE
ANY ELBOWS
LISTED VENT C AP
Applications manual
MINIMUM 6
FEE T (1.8M)
GWH 425 HN Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 7" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 11" W.C.
Maximum: 14" W.C.
Water pressure
(Static)
Minimum: 30 PSI
Minimum well pressure: 40 PSI
Maximum: 150 PSI
Electrical supply 120VAC - plugs in
Vertical venting 5" minimum diameter - natural
draft
Horizontal venting AQ4 horizontal vent kit required
for horizontal terminations
Fig. 2 Venting confi guration
Installation guidelines:
Venting:
5" minimum diameter — do not reduce vent size
Refer to installation manual for vent material options
Do not combination vent with any power vented appliances
Establish a one-foot rise before any elbows
Minimum vent height - 6 feet
Horizontal sections must slope upwards at least ¼" for every foot
of the horizontal length and be properly supported
Gas piping:
Heater will not function properly without adequate supply gas
pressure
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable drain
Minimum piping diameter is ¾"
Do not solder directly to connections on the bottom of the unit
Use full port ball valves for isolation valves
Application manual | 11.2007
Bosch Water Heating
Applications manual
2.9 Bosch GWH 425 PN
Features:
Standing pilot ignition
78% thermal effi ciency
Endless hot water for one major application at a time
Modulating gas valve — constant temperature at varying flow rates
Model GWH 425 PN N for natural gas (NG) supply
Model GWH 425 PN L for liquid propane (LP) supply
15-year warranty
GWH 425 PN Technical Specifi cations
Power input Natural Gas: 31,000 - 117,000 BTU
LP Gas: 31,000 - 117,000 BTU
Minimum fl ow to activate 0.6 gallons per minute (gpm)
Flow rates 45˚F rise @ 4.2 gpm
55˚F rise @ 3.4 gpm
65˚F rise @ 2.9 gpm
77˚F rise @ 2.4 gpm
90˚F rise @ 2.1 gpm
Thermal Effi ciency NG: 78% LP: 78%
Dimensions 25.75" h x 16.75" w x 8.5" d
Weight 33 lbs.
Modulating gas valve yes
Ignition Standing pilot
Accessories Horizontal vent kit (AQ4) - power
vent kit for horizontal venting
GWH 425 PN Installation Clearances
Top (A) 12"
Front (B) 4"
Back 0"
Sides 4"
Floor (C) 12"
LISTED GAS VENT
ESTABLISH A ONE
FOOT RISE BEFORE
ANY ELBOWS
LISTED VENT C AP
| 13
MINIMUM 6
FEE T (1.8M)
GWH 425 PN Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 7" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 11" W.C.
Maximum: 14" W.C.
Water pressure Minimum: 30 PSI
Maximum: 150 PSI
Electrical supply 120VAC - plugs in
Vertical venting 5" minimum diameter - natural
draft
Horizontal venting AQ4 horizontal vent kit required
for horizontal terminations
Fig. 4 Venting confi guration
Installation guidelines:
Venting:
5" minimum diameter — do not reduce vent size.
Refer to installation manual for vent material options
Do not combination vent with any power vented appliances.
Establish a one-foot rise before any elbows
Minimum vent height - 6 feet.
Horizontal sections must slope upwards at least ¼" for every foot
of the horizontal length and be properly supported.
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use full port ball valves for isolation valves.
Applications manual | 11.2007Bosch Water Heating
|
14
2.10 Bosch GWH 260 PN
Features:
Standing pilot ignition
78% thermal effi ciency
Mounts on wall for easy installation
Venting: 4" double wall B-vent — natural draft
Modulating gas valve — constant temperature at varying flow rates
Model GWH 260 PN N for natural gas (NG) supply
Model GWH 260 PN L for liquid propane (LP) supply
15-year warranty
Applications manual
GWH 260 PN Installation Clearances
Top (A) 12"
Front (B) 4"
Back 0"
Sides 4"
Floor (C) 12"
GWH 260 PN Technical Specifi cations
Gas input Natural Gas: 30,735 - 74,900 BTU
LP Gas: 30,735 - 74,900 BTU
Minimum fl ow to activate 0.6 gallons per minute (gpm)
Flow rates 45˚F rise @ 2.6 gpm
55˚F rise @ 2.1 gpm
65˚F rise @ 1.7 gpm
77˚F rise @ 1.5 gpm
90˚F rise @ 1.3 gpm
Thermal Effi ciency NG: 78% LP: 78%
Dimensions 28.8" h x 12.2" w x 8.5" d
Weight 25 lbs.
Modulating gas valve yes
Ignition Standing pilot
GWH 260 PN Installation Specifi cations
Gas connection ¾" Male NPT
Water connections ¾" Male NPT
NG gas pressure Minimum: 7" W.C.
Maximum: 14" W.C.
LP gas pressure Minimum: 11" W.C.
Maximum: 14" W.C.
Water pressure
(Static)
Minimum: 30 PSI
Minimum well pressure: 40PSI
Maximum: 150 PSI
Electrical supply 120VAC - plugs in
Venting 4" double wall B-vent - natural
draft
LISTED VENT C AP
MINIMUM 6
FEE T (1.8M)
LISTED GAS VENT
ESTABLISH A ONE
FOOT RISE BEFORE
ANY ELBOWS
Fig. 4 Venting confi guration
Installation guidelines:
Venting:
4" minimum diameter — do not reduce vent size.
Refer to installation manual for vent material options
Do not combination vent with any power vented appliances.
Establish a one-foot rise before any elbows
Minimum vent height - 6 feet.
Horizontal sections must slope upwards at least ¼" for every foot
of the horizontal length and be properly supported.
Application manual | 11.2007
Gas piping:
Heater will not function properly without adequate supply gas
pressure.
Any appliance connector should be ¾" minimum diameter
Plumbing:
Install the included pressure relief valve and pipe to suitable
drain.
Minimum piping diameter is ¾".
Do not solder directly to the bottom of the unit.
Use full port ball valves for isolation valves.
Bosch Water Heating
Applications manual
2.11 Powerstream Pro RP17PT, RP27PT
| 15
Features:
Over 90% effi ciency rating
10-year warranty on heat exchanger
Durable polymer construction
External temperature control knob
Thermal cut-out for safety
Flow sensor to provide a constant output temperature
Provides an ENDLESS supply of hot water
Weighs less than 25 pounds and fi ts virtually anywhere
No temperature/pressure relief valve necessary (unless required
by local codes)
Technical Specifi cations
Model RP17PT RP27PT
Effi ciency 90% 94%
Dimensions
15 ½" x 15 ¼" x 4 ½" 15 ½" x 15 ¼" x 4 ½"
Weight 20 lbs. 22 lbs.
Water fi ttings ¾" Male NPT ¾" Male NPT
Activation rate 0.6 gpm 0.8 gpm
Electrical requirements
Volts 240 240
Kilowatts 17.25kW 26.85kW
Amps
Wire
size
U.S.A
Canada
U.S.A
Canada
80 (2x40 amps)
80 (1x80 amps)
8 AWG
(4 conductors & ground)
Check Canadian
Electrical Code
(C22.1-02)
120 (3x40 amps)
120 (1x120amps)
8 AWG
(4 conductors & ground)
Check Canadian
Electrical Code
(C22.1-02)
Phase Single Single
Maximum fl ow rate at given temperature rise
45°F Rise 2.6 gpm 4.0 gpm
50°F Rise 2.3 gpm 3.7 gpm
60°F Rise 2.0 gpm 3.0 gpm
70°F Rise 1.7 gpm 2.6 gpm
80°F Rise 1.5 gpm 2.2 gpm
Installation guidelines:
Electrical:
Minimum electrical service for RP17PT is 150 amps.
Minimum electrical service for RP27PT is 200 amps.
Minimum wire size for both models is 8 AWG.
Plumbing:
Do not solder directly to connections on the bottom of the unit.
Use unions to facilitate easy future maintenance.
Use full port ball valves for isolation valves.
RP17PT terminal block
2 independent
40 amp double-pole
circuit breakers
Fig. 5 RP17PT Electrical Connections
RP27PT terminal block
3 independent
40 amp double-pole
circuit breakers
Fig. 6 RP27PT Electrical Connections
Applications manual | 11.2007Bosch Water Heating
Loading...