Conditions: Upper or Lower Sensor Reading Faulty, High Water Temperature, or suspect thermostat is not accurate.

SERVICE PROCEDURE PDV24-I

Thermostat Circuit Testing

Sensor Resistance Testing

Upper Sensor

1.Determine resistance value of upper sensor using an ohmeter. Test across grey wires.

2.Draw quart of water off T&P valve. Using a thermometer, determine water temperature.

3.Use table below to verify correct resistance per water temperature measured.

Lower Sensor:

1.Determine resistance value of lower sensor. Test across center wire (common) to each outside wire. Resistance of both thermistors in the lower sensor should be close to each other. If the resistance values for both thermistors are not close to each other, replace the lower sensor. The dual thermistors are used to provide high limit protection in case the thermostat circuit fails to shut off the water heater.

2.Draw quart of water off Drain Valve. Using a thermometer, determine water temperature.

3.Use table below to verify correct resistance per water temperature measured.

Upper thermister location

(applicable models)

Checking resistance of

upper sensor

Lower thermister

access located inside

control box.

Are readings N

Replace

 

correct?

 

thermister

Checking resistance of

Y

 

 

 

 

lower sensor (center and

Check harness

 

Replace

outside pins)

N

 

continuity.

 

 

harness

CAUTION

Continuity okay?

 

 

 

Y

 

 

Be Careful When Making Resistance

 

 

Measurements Not to Damage or

 

 

 

Replace

 

 

Deform Connectors or Connector Pins.

 

 

 

control board

 

Sensor Resistance at Various Temperatures

 

 

Example: If water temperature is 84°F, then the resistance through the sensor would be 8449 (see shaded area).

NOTE: Sensor resistance increases as the temperature falls.

In Degrees F

 

 

 

 

 

 

 

 

 

 

 

°F

0

1

2

3

4

5

6

7

8

9

40

26109

25400

24712

24045

23399

22771

22163

21573

21000

20445

50

19906

19383

18876

18383

17905

17440

16990

16553

16128

15715

60

15314

14925

14548

14180

13823

13477

13140

12812

12494

12185

70

11884

11592

11308

11032

10763

10502

10248

10000

9760

9526

80

9299

9078

8862

8653

8449

8250

8057

7869

7685

7507

90

7333

7165

7000

6839

6683

6531

6383

6238

6098

5961

100

5827

5697

5570

5446

5326

5208

5094

4982

4873

4767

110

4663

4562

4464

4368

4274

4183

4094

4006

3922

3839

120

3758

3679

3602

3527

3453

3382

3312

3244

3177

3112

130

3048

2986

2925

2866

2808

2752

2697

2643

2590

2538

140

2488

2439

2391

2344

2298

2253

2209

2166

2124

2083

150

2043

2004

1966

1928

1891

1856

1820

1786

1753

1720

160

1688

1656

1625

1595

1566

1537

1509

1481

1454

1427

170

1402

1376

1351

1327

1303

1280

1257

1235

1213

1191

180

1170

1150

1129

1110

1090

1071

1053

1035

1017

999

190

982

965

949

933

917

901

886

871

857

842

200

828

814

801

788

775

762

749

737

725

713

26

Page 26
Image 26
Bradford-White Corp PDV80T300, D80T725, D65T625, PDV100S150, PDV100S250, PDV100T360, PDV80S250 Upper Sensor, Lower Sensor

PDV80T300, PDV100S150, PDV100T360, PDV80S150, D65T625 specifications

Bradford-White Corporation is renowned for its quality water heating solutions, with a diverse range of products designed to meet various residential and commercial needs. Among their stellar offerings are the D80T725, PDV100S200, PDV100S250, PDV80S250, and PDV802200 models, each equipped with advanced technologies and features that set them apart in the market.

The D80T725 is an innovative 80-gallon water heater that employs a powerful 75,000 BTU burner, ensuring rapid water heating for larger households. One of its key features is the Defender Safety System, which provides exceptional protection against potential hazards. The advanced electronic control system enhances efficiency and reliability, making it an ideal choice for energy-conscious consumers. Additionally, the tank's unique insulation helps maintain water temperature longer, reducing energy costs.

Moving to the PDV series, the PDV100S200 and PDV100S250 are dynamic, direct vent gas water heaters with capacities of 100 gallons and impressive BTU inputs. These models utilize a proper venting system that draws air from outside, ensuring that indoor air quality remains uncompromised. Both models feature Bradford-White's patented hydrojet total performance system, improving heat transfer by minimizing sediment buildup. This technology prolongs the lifespan of the unit while maximizing energy efficiency.

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In summary, whether you opt for the D80T725 or one of the PDV models, you can expect a blend of performance, efficiency, and advanced technology. Bradford-White's commitment to quality and innovation ensures that each product meets the demands of modern consumers, making them a leading choice in the water heating industry.