Model # HJ640NBDSCGA Official Maytag water heater

Here are the diagrams and repair parts for Official Maytag HJ640NBDSCGA water heater, as well as links to manuals and error code tables, if available.

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Error Codes

Model diagram and schematic

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ALL PARTS

Showing 10 of 44 parts |

#16A

Body diagram

Flue baffle

Part #66001235

The manufacturer no longer makes this part, and there's no substitute part

#23

Body diagram

6" vent wall

Part #66001444

The manufacturer no longer makes this part, and there's no substitute part

Body diagram

Drain valve

Part #66001181

The manufacturer no longer makes this part, and there's no substitute part

#12

Body diagram

Nipple

Part #66001311

The manufacturer no longer makes this part, and there's no substitute part

#16B

Body diagram

Flue baffle

Part #66001347

The manufacturer no longer makes this part, and there's no substitute part

Water Heater Temperature And Pressure Relief Valve 66001216

#13

Body diagram

Water heater temperature and pressure relief valve

Part #66001216

The manufacturer no longer makes this part, and there's no substitute part

#3A

Body diagram

Thermostat

Part #66001183

The manufacturer no longer makes this part, and there's no substitute part

Body diagram

Tube pilot

Part #66001188

The manufacturer no longer makes this part, and there's no substitute part

#18A

Body diagram

Gasket, adap

Part #66001239

The manufacturer no longer makes this part, and there's no substitute part

Body diagram

Burner orifice

Part #66001025

The manufacturer no longer makes this part, and there's no substitute part

Most common symptoms to help you fix your water heaters

Choose a symptom to see related water heater repairs.

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Why isn't my water heater making the water hot enough?

Main causes: thermostats need adjustment, water heater capacity too low, bad heating element, thermostat failure, excess…

Why is there water in my water heater's drain pan?

Main causes: loose water pipe fittings, leaky drain valve, bad temperature-pressure relief valve, leaky heating element,…

Why does my hot water smell like rotten eggs?

Main causes: water supply needs chlorine treatment, anode rod too reactive…

Why isn't my water heater heating my water?

Main causes: lack of power, no gas supply, thermostat limit switch tripped, bad element, bad thermostat, gas valve failu…

Why isn't my water heater making enough hot water?

Main causes: broken heating element, thermostat failure, excessive tank sediment, tank size too small, burner valve asse…

Why is my water heater making the water too hot?

Main causes: thermostat temperature set too high, thermostats need adjustment, faulty thermostat, shorted heating elemen…

Why is my water heater's pressure relief valve dripping water?

Main causes: faulty pressure relief valve, water is overheating…

Effective articles & videos to help repair your water heaters

Use the advice and tips in these articles and videos to get the most out of your water heater.

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Wiring schematic symbols explained video

Model # HJ640NBDSCGA Official Maytag water heater

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your water heaters

Why isn't my water heater making the water hot enough?

Why is there water in my water heater's drain pan?

Why does my hot water smell like rotten eggs?

Why isn't my water heater heating my water?

Why isn't my water heater making enough hot water?

Why is my water heater making the water too hot?

Why is my water heater's pressure relief valve dripping water?

Effective articles & videos to help repair your water heaters

Wiring schematic symbols explained video

Using a wiring schematic to trace a current video

Easy DIY water heater repairs

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