A.O. Smith 240 T-H3J User manual

A.O. Smith Water Products
Company
500 Tennessee Waltz Parkway
Ashland City, TN 37015
Toll Free: 1-877-737-2840
240 (T-H3J), 340 (T-H3S)
and 540 (T-H3) Models
On-Demand Water Heater
Service Manual
TRGSM00713

2Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
Table of Contents
പϭ^ƉĞĐŝĨŝĐĂƚŝŽŶƐ
പϮdžƚĞƌŝŽƌǀŝĞǁ
പϯ/ŶƚĞƌŝŽƌǀŝĞǁ
പϰ>ŝƐƚŽĨŵĂŝŶĐŽŵƉŽŶĞŶƚƐŝŶƚŚĞŝŶƚĞƌŝŽƌǀŝĞǁ
ϱ^ĐŚĞŵĂƟĐĚŝĂŐƌĂŵ.
6. Wiring diagram.................................................................................................................
ϳtŝƌŝŶŐĚŝĂŐƌĂŵĐŚĞĐŬƉŽŝŶƚƐĨŽƌĚŝĂŐŶŽƐŝƐ
ϴ;ͿZĞƐŝƐƚĂŶĐĞǀĂůƵĞƐŽĨƚŚĞƚĞŵƉĞƌĂƚƵƌĞƚŚĞƌŵŝƐƚŽƌƐ
ϴ;ͿZĞƐŝƐƚĂŶĐĞǀĂůƵĞƐŽĨƚŚĞƚĞŵƉĞƌĂƚƵƌĞĞdžŚĂƵƐƚƚŚĞƌŵŝƐƚŽƌƐ
ϵKƉĞƌĂƟŽŶĂůŇŽǁĐŚĂƌƚ
ϭϬŽŵƉŽŶĞŶƚƐƉĞĐŝĮĐĂƟŽŶƐ
ϭϭ&ĂƵůƚŶĂůLJƐŝƐΘ^ƉĞĐŝĮĐĂƟŽŶƐ
ϭϮŽŶƚƌŽůƐĂŶĚƐĞƫŶŐƐ
13. Components diagrams......................................................................................................
14. Parts list............................................................................................................................
15. Revisions...........................................................................................................................
3
4
6
10
13
14
16
18
19
20
21
47
58
89
93
104

3Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
1. Specifications
Model 240
Indoor
(T-H3J-DV)
240
Outdoor
(T-H3J-OS)
340
Indoor
(T-H3S-DV)
340
Outdoor
(T-H3S-OS)
540
Indoor
(T-H3-DV)
540
Outdoor
(T-H3-OS)
Dimensions inch ,ϮϮϰdžtϭϳϳdžϭϬϳ
ϱϳϬ;,ͿdžϰϱϬ;tͿdžϮϳϮ;Ϳ
mm
Weight lbs. (kg) 58 (26.3) 58 (26.2) 58 (26.3) 58 (26.2) 58 (26.8) 58 (26.9)
Combustion
/EWhd
dhŚ
DĂdž 160,000 180,000 199,000
Min Propane 13,000
Natural gas 15,000
Combustion
system
/ŶƐƚĂůůĂƚŝŽŶ
Power vent
/ŶƐƚĂůůĂƚŝŽŶ Direct-vent
/ŶĚŽŽƌ Outdoor Direct-vent /ŶĚŽŽƌ Outdoor Direct-vent /ŶĚŽŽƌ Outdoor
Fan motor WtDƚƵƌďŽĨĂŶ
DĂŶŝĨŽůĚ
Pressure*
("W.C.)
DĂdž Propane 2.2
Natural 1.9
Propane 2.2
Natural 2.0
Propane 2.6
Natural 2.4
Propane 2.7
Natural 2.4
Propane 3.2
Natural 2.8
Propane 3.2
Natural 2.9
Min Propane 0.6
Natural 0.7
Propane 0.7
Natural 0.7
Propane 0.6
Natural 0.7
Propane 0.7
Natural 0.7
Propane 0.6
Natural 0.7
Propane 0.7
Natural 0.7
Water control
Flow rate GPM 0.5 to 6.6 0.5 to 8.0 0.5 to 10.0
Available
set
temperatures
°F
(°C)
100 to 140 (38 to 60)
ĚĞĨĂƵůƚϭϮϬ;ϰϵͿ
100 to 185 (38 to 85)
ĚĞĨĂƵůƚϭϮϬ;ϰϵͿ
Temperature
/WƐǁŝƚĐŚ
settings
°F
(°C) 120 (49), 140 (60)
Bypass valve E Yes
Thermistors ϮƚŚĞƌŵŝƐƚŽƌƐ;/ŶKƵƚͿ 3 thermistors
;/ŶKƵƚ,ĞĂƚĞdžĐŚĂŶŐĞƌͿ
Operation
Temperature
control
dĞŵƉĞƌĂƚƵƌĞĐŽŶƚƌŽůůĞƌŝƌĞĐƚsĞŶƚ/ŶĚŽŽƌŵŽĚĞůƐ
dĞŵƉĞƌĂƚƵƌĞƌĞŵŽƚĞĐŽŶƚƌŽůůĞƌ;dDͲZϰϬͿKƵƚĚŽŽƌŵŽĚĞůƐ
PCB model 240
WĂƌƚηϯϭϵϭϰϯͲϱϰϯ;<ϭϴϲ)
340
WĂƌƚηϯϭϵϭϰϯͲϱϰϰ;<ϭϳϱͿ
540
WĂƌƚηϯϭϵϭϰϯͲϱϰϱ;<ϭϳϲͿ
/ŶĚŝĐĂƚŽƌƐ ^ƚĂŶĚͲďLJ>
Power supply
control Surge absorber & Power ON-OFF switch
Features
Freeze
protection
Ceramic heaters (All models) and
ƵƚŽͲĨŝƌŝŶŐƐLJƐƚĞŵ;KŶůLJϱϰϬŝƌĞĐƚsĞŶƚ/ŶĚŽŽƌŵŽĚĞůƐ;dͲ,ϯͲsͿŵŽĚĞůƐͿ
^ĞůĨͲ
combustion
improvement
Air-Fuel Ratio Detection System
ĂƐLJͲ>ŝŶŬ
system E zĞƐ;hƉƚŽϰƵŶŝƚƐͿ
Multiple-
system E zĞƐ;hƉƚŽϮϬƵŶŝƚƐͿ
ΎdŚĞŵĂŶŝĨŽůĚƉƌĞƐƐƵƌĞŵĞĂƐƵƌĞŵĞŶƚŝƐďĂƐĞĚŽŶĐŽŶĚŝƚŝŽŶƐǁŝƚŚŽƵƚĨƌŽŶƚĐŽǀĞƌ

4Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
2. Exterior view
Direct Vnet Indoor models
Side view
Front view
7-7/8" (199 mm)
GAS 5-1/8" (131 mm)
COLD 6-3/4" (172 mm)
HOT 5-1/2" (140 mm)
7-1/2" (189 mm)
GAS 5-7/8" (147 mm)
Condensate drain port
COLD 5/8" (17 mm)
HOT 4-3/4" (120 mm)
17-5/8" (448 mm)
6-1/4" (159 mm)
5-3/4" (147 mm)
120 VAC 3" (77 mm)
120 VAC 6-7/8" (174 mm)
∅
Drain port
Female
10-3/4" (272mm)
22-1/22" (570 mm)
Condensate drain port
4" (102 mm)
2-5/8" (68 mm)
Exhaust
Intake
Female
∅
7-7/8" (199 mm)
7-1/2" (189 mm)
7" (180 mm) 4" (101 mm)
17-3/4" (450 mm)
HOT 4-3/4" (120 mm)
6-3/4" (170 mm)
COLD 5/8" (17 mm)
GAS 5-3/4" (147 mm)
Condensate drain port
23-5/8" (600 mm)
2-5/8" (65 mm)
5-3/4" (147 mm)
11-1/4" (285 mm)
1/2 (13 mm)
GAS 5-1/8" (131 mm)
HOT 5-1/2" (140 mm)
COLD 6-3/4" (172 mm)
Condensate drain port
6-1/4" (159mm)
4" (102 mm)
24-7/8" (631 mm)
120 VAC 3" (77 mm)
Drain port 6" (152 mm)
120 VAC 6-7/8" (174 mm)
Bottom view Top view

5Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
Outdoor models
Side view
Front view
17-5/8" (448 mm)
6-1/4" (159 mm) COLD 5/8" (17 mm)
120 VAC 3" (77 mm)
HOT 5-1/2" (140 mm)
HOT 4-3/4" (120 mm) 7-1/2" (189 mm)
Condensate drain port
GAS 5-1/8" (131 mm)
COLD 6-3/4" (172 mm)
7-7/8" (199 mm)
Drain port
7-1/2" (189 mm)
10-3/4" (272 mm)
22-1/2" (570 mm)
120 VAC
Condensate drain port
7-7/8" (199 mm)
Condensate drain port
11" (281 mm)
1/2" (13 mm)
120 VAC 3" (77 mm)
GAS (131 mm)
HOT (140 mm)
COLD 6-3/4" (172 mm)
Condensate drain port
COLD 5/8" (17 mm)
GAS 5-3/4" (147 mm)
HOT 4-3/4" (120 mm)
6-3/4" (170 mm)
1-1/2" (37 mm)
11-1/4" (285 mm)
120 VAC 6-1/4" (159 mm)
17-3/4" (450 mm)
7" (180 mm)
23-5/8" (600 mm)
24-7/8" (631 mm)
3-5/8" (92 mm)
4-1/2" (114 mm)
Drain port 6" (152 mm)
Bottom view Top view

6Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
3. Interior view
240 Indoor (T-H3J-DV)
340 Indoor (T-H3S-DV)
1
2
3
4
5
6
79
10
11
12
13
14
15
16
18
19
20
21
22
23 24
26
28
27
29
30
31
31
33
33
17
33
37
38
34
39
32
32
REMOTE
CONTROLLER
OFF ON
AC120V
8
25

7Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
240 Outdoor (T-H3J-OS)
340 Outdoor (T-H3S-OS)
1
2
3
4
5
6
78
9
10
11
12
13
14
15
16
18
19
20
21
22
23 24
25
26
28
27
29
35
30
31
31
33
33 17
34
39
32
32
REMOTE
CONTROLLER
OFF ON
AC120V

8Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
540 Indoor (T-H3-DV)
1
2
3
4
5
6
78
9
10
11
12
13
14
15
16
18
19
20
21
22
23 24
25
26
28
27
29
35
30
31
31
33
33 17
33
36
37
38
34
39
32
32
AC120V
REMOTE
CONTROLLER
OFF ON

9Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
540 Outdoor (T-H3-OS)
1
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78 9
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35
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17
36
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39
32
32
REMOTE
CONTROLLER
AC120V
OFF ON

10 Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
4. List of main components in the interior view
No. Description
Items# in
components
diagram
Part #
240, 340 and
540 models
T-H3J, T-H3S and
T-H3 models
1. Case assembly
/ŶĚŽŽƌ
models 001
E <ϭϱϵ
Outdoor
models E <ϭϲϰ
2.
DĂŶŝĨŽůĚ
assembly with
gas valve
assembly
>WŵŽĚĞů
102
319143-515 <ϭϴϭ
NA model 319143-516 <ϭϴϮ
3. Computer board 701
319143-543
(240 models)
<ϭϴϲ
(T-H3J models)
319143-544
(340 models)
<ϭϳϱ
(T-H3S models)
319143-545
(540 models)
<ϭϳϲ
(T-H3 models)
4. /ŐŶŝƚĞƌ 711 319143-479 <ϭϱϯ
5. Gas valve
assembly
>WŵŽĚĞů /ŶĐůƵĚĞĚŝŶ
#102
319143-515 <ϭϴϭ
NA model 319143-516 <ϭϴϮ
6. Water inlet 404 319143-193 <<ϭh
7. Water outlet 409 319143-530 <ϮϬϴ
8. /ŶůĞƚƚŚĞƌŵŝƐƚŽƌ 407
319143-214
;ϮϰϬϯϰϬŵŽĚĞůƐͿ
<<ϰ:
;dͲ,ϯ:dͲ,ϯ^ŵŽĚĞůƐͿ
319143-465
(540 models)
<ϭϯϳ
(T-H3 models)
9. Outlet thermistor 408
319143-529
;ϮϰϬϯϰϬŵŽĚĞůƐͿ
<ϮϬϳ
;dͲ,ϯ:dͲ,ϯ^ŵŽĚĞůƐͿ
319143-190
(540 models)
<<ϭ
(T-H3 models)
10. KǀĞƌŚĞĂƚĐƵƚͲŽĨĨĨƵƐĞ 413 319143-149 <ϯϯϯ
11. Burner assembly 101 319143-514 <ϭϵϮ
12. Hi-limit switch 412
319143-228
;ϮϰϬϯϰϬŵŽĚĞůƐͿ
DϮϭϮ
;dͲ,ϯ:dͲ,ϯ^ŵŽĚĞůƐͿ
319143-095
(540 models)
<Eϯϰ
(T-H3 models)