37AHB Series Hydronic Furnace
The optimum in hydronic technology, the newly
designed Rinnai® multi-position hydronic furnaces
offer a unique solution for a wide variety of small- and
medium-sized residential and light commercial
applications. They are compact and ready to fit in tight
spaces which may include, but not limited to, attics,
basements, closets, crawlspaces, and utility rooms.
Intelligent Microprocessor Controller
The 37AHB units are equipped with an intelligent
microprocessor control that allows for domestic hot
water priority and adapts to available hot water flow for
space heating by automatically regulating the pump
and fan sequence to maximize comfort.
Fine Tuned to Work with Rinnai Tankless
Water Heaters
These unique hydronic furnaces are designed to work
in combination with our line of Rinnai® tankless water
heaters to deliver heating capacities that cover a wide
spectrum of residential and light commercial heating
applications. When combined, the units form the Rinnai
Tankless Heating System, the first matched, tankless
hydronic heating solution in the industry!
PATENT PENDING
FEATURES
Specifications
Air Delivery
●
Four models covering a range of heating capacities
○
27,100 to 96,300 BTU/hour
●
Multi-position (upflow, downflow, horizontal left,
horizontal right) without modifications *
○
Modifiable for side-entry return air
●
Low-flow, high-head pump custom designed to work
with Rinnai's tankless water heaters
●
Integrated control board with learning algorithm
●
No combustion air infiltration losses when used with
a Rinnai tankless water heater
●
Four selectable heat blower off delay times
●
Multi-speed motors (ECM)
●
Strong 20-gauge steel cabinet
○
Galvanized, painted
○
Fully insulated cabinet
○
Low 34 inch profile
●
Multi-position control box
●
Designed for serviceability
●
Schrader valves to purge air from the system
●
Integral filter rack with filter
Fan motor with ECM technology
*
NOTE: The unit is not designed to be installed on its back or
face down.
37AHB Series Hydronic Furnace
† Tested in accordance with ANSI/ASHRAE Standard 37-Latest edition.
‡ Airflows shown are nominal (blower speeds are factory set). For air
delivery other than stated, refer to the Air Delivery & Performance table.
†† Required filter sizes shown are based on the larger of the AHRI (Air
Conditioning & Refrigeration Institute) rated cooling airflow or the heating
airflow velocity of 300 ft/min for throwaway type or 450 ft/min for
high-capacity type.
Side intake filter to be (1) 20”x20”x1” typical for all models.
Air filter pressure drop for non-standard filters must not exceed 0.08 in. wg.
This product is manufactured in a facility registered by UL to ISO 9001.
File No. A6887.
Part of the Rinnai Tankless Heating System
AHB90
AHB75
AHB60
AHB45
600000060 (7/2010)
UL recognized
component
This product is manufactured in a
facility registered by UL to ISO
9001.
37AHB Series Hydronic Furnace
0
0.1
0.
2
0.3
0.
4
0.5
0.
6
0.7
0.
8
0.9
1.
0
TA
P
3 (
H
)
2.
0
948
921
891
868
841
819
795
772
701
596
567
TA
P
4 (
M
)
2.
0
921
891
864
836
812
788
768
742
699
594
559
TA
P
5 (
L)
1.
5
803
768
740
712
682
652
628
596
569
541
510
TA
P
1 (
H
)
3.
0
1343
1318
1296
1270
1248
1225
1197
1168
1109
1025
889
TA
P
2 (
M
H
)
2.
5
1148
1128
1103
1072
1045
1012
984
955
937
908
690
TA
P
4 (
M
L)
2.
0
971
942
911
880
847
817
784
751
715
680
642
TA
P
5 (
L)
1.
5
844
810
777
734
698
665
626
581
533
504
466
TA
P
1 (
H
)
4.
0
1700
1666
1635
1604
1576
1543
1518
1492
1465
1430
1402
TA
P
2 (
M
H
)
3.
5
1561
1524
1490
1456
1428
1396
1364
1330
1230
1265
1224
TA
P
3 (
M
L)
3.
0
1391
1350
1320
1281
1245
1209
1190
1131
1090
1064
1031
TA
P
4 (
L)
2.
5
1222
1174
1140
1100
1063
1014
979
937
887
829
777
TAP 1
(
H
)
5.
0
1934
1889
1857
1818
1784
1750
1715
1680
1568
1491
1377
TA
P
2 (
M
H
)
4.
0
1777
1732
1694
1650
1630
1592
1553
1517
1464
1441
1361
TA
P
3 (
M
L)
3.
5
1573
1530
1490
1448
1417
1372
1327
1293
1253
1221
1175
TAP 4
(
L)
3.
0
1400
1351
1317
1275
1225
1183
1134
1095
1053
1011
951
37A
H
B
090 w
ith
RC
98
HP
, RC
80
H
P
,
R
94LS
, or
R
75LS
37A
H
B
060 w
ith
RC
98
HP
, RC
80
H
P
,
R
94LS
, R
75LS
, or
V
53i
AI
R
F
LO
W
(
C
FM
)
N
O
M
IN
A
L
A
IR DE
L
IV
E
RY
C
H
A
R
T
(
B
O
T
T
O
M
O
R
S
IDE
RE
T
URN w/
F
IL
T
E
R
)
Ex
te
rn
al
St
at
ic
Pr
es
su
re
(
ESP)
UNI
T S
IZ
E
ECM
SPEED
TA
P
SU
PPO
R
TS
CO
O
LI
N
G
CAP.
R
A
N
G
E
(T
O
N
S
)
37A
H
B
045 w
ith
RC
98
HP
, RC
80
H
P
,
R
94LS
, R
75LS
, or
V
53i
37A
H
B
075 w
ith
RC
98
HP
, RC
80
H
P
,
R
94LS
, or
R
75LS
●
C
M
Y
CM
MY
CY
CMY
K
37AHB spec sheet cover (7-2010).ai 7/23/2010 10:16:37 AM
37AHB spec sheet cover (7-2010).ai 7/23/2010 10:16:37 AM
