Q175S / Q205S Condensing Boiler
Standard Features
• Onboard outdoor reset control system with sensor standard
• Prebuilt plumbing kit with insulated Low Loss Header
• Priority DHW standard (3 way valve not included)
• Domestic hot water plate warming
• Modulating Ceramic premix burner
• 5:1 turn down ratio
• Spark ignition
• Exceeds SCAQMD 1146.2 Low NO
• Stainless Steel Water tube condensing heat exchanger
• Direct Vent sealed combustion
• Concentric and twin pipe venting adapters included
• Approved for room and closet installations
requirements
x
SPECIFICATIONS
General Specifications
Boiler
Water content gal 1.8 1.8
Max. supply boiler
temperature
Max operating pressure psi 45 45
Relief valve rating MBH 375 375
Relief valve pressure rating psi 30 30
Units
°F 176 176
Model
Q175S Q205S
Boiler
Model
Optional Accessories
• 3 way valve DHW kit
• RS100 Single zone controller
• Flue Gas temperature sensor
• Room Air Filter
• NG to LP conversion Kit
• LP to NG Conversion Kit
Performance Specifications
Units
Fuel Type NG/LP NG/LP
Input MBH 175 205
Heating Capacity MBH 161 189
AFUE (I=B=R) % 95.7 95.7
Part Load Efficiency
(EN677)
% 98.5 98.5
Boiler Model
Q175S Q205S
Dry weight lbs 141 141
Electrical Specifications
Min inlet gas pressure NG "W.C. 4.0" 4.0"
Max inlet gas pressure NG "W.C. 10.5" 10.5"
Min inlet gas pressure LP "W.C. 8.0" 8.0"
Max inlet gas pressure LP "W.C. 14.0” 14.0”
Max equivalent exhaust
vent length
Max equivalent combustion
air vent length
Approved venting materials
Rinnai is continually updating and improving products; therefore, specifications are subject to change without prior
notice. Local, state, provincial and federal codes must be adhered to prior to installation.
© 2011 Rinnai Corporation
ft 80 40
ft 80 40
Polypropylene,
Stainless Steel,
PVC, CPVC
Units
Electrical Voltage Mains V/Hz 120/60 120/60
Electrical Voltage Controls V 24 24
Power Consumption Max
Load
Power Consumption Stand
by Load
Recommended Circuit
breaker rating
Q175S / Q205S SP 2/2011
W 210 234
W 14 14
A 15 15
Boiler Model
Q175S Q205S
DIMENSIONS
Q175S / Q205S
A Height 26.8 / 680
B Width 26 / 660
C Depth 15.2 / 385
D Left side / vent 19.5 / 495
Center to center / vent and air
E
supply
F Back / vent 10.6 / 270
G Left side / gas pipe 2.6 / 65
H Left side / supply pipe 7.3 / 185
J Left side / return pipe 17.5 / 445
K Left side / condensate pipe 20.9 / 530
P Pipe length of g 0.7 / 18
Q Pipe length of c 2 / 50
R Pipe length of e, f, k, r, and w 2.3 / 60
S Back / center of pipe c 1 / 25
T Back / Center of pipe g 1.6 / 40
Q175S, Q205S
inch / mm
4.7 / 120
2.0”
50mm
2.1”
54mm
[5.6”
142mm
18.6”
474mm
4.7”
120mm
5.2”
133mm
15”
381mm
17.2”
438mm
10.2”
260mm
12”
305mm
19.7”
501mm
Back, / center of pipe e, f, k, r,
U
and w
Pipe length vent co-axial
V
Pipe length vent parallel
Clearances
Minimum required
Top 2 / 50 10 / 250
Back 0 0
Front 6 / 150 24 / 600
Left side 2 / 50 2 / 50
Right
side
Floor /
Ground
Vent 0 0
clearance to
combustibles and
non-combustibles
2 / 50
2.6 / 65
5.8 / 147
Recommended
service
clearances
inch / mm
2 / 50 2 / 50
12 / 300 30 / 762
inch / mm
Rinnai Corporation • 103 International Drive • Peachtree City, GA 30269 • Toll-Free: 1-800-621-9419 • Fax: 678-364-8643 • www.rinnai.us