Model # A42-20 Official Goodman air handler with coil

Here are the diagrams and repair parts for Official Goodman A42-20 air handler with coil, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 40 parts |

#12

Air handler diagram

Transformer

Part #B11416-43

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

Air handler diagram

Heating elem

Part #B10374-67

Replaced by #B1037485S

$80.25 |

7% OFF Phone Price : $86.25

In Stock

Qty

#7A

Air handler diagram

Heating elem

Part #B10374-68

Replaced by #B1037488S

$141.73 |

8% OFF Phone Price : $153.73

In Stock

Qty

#11

Air handler diagram

Time delay

Part #B13707-38

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

#16

Air handler diagram

Blower wheel

Part #B13680-36

Replaced by #B1368036S

$102.07 |

11% OFF Phone Price : $114.07

In Stock

Qty

#9A

Air handler diagram

Sequencer a-

Part #B12565-52

Replaced by #24A34-3

$29.43 |

17% OFF Phone Price : $35.43

In Stock

Qty

#23

Air handler diagram

Plastic hori

Part #17559-30

Replaced by #B1755930L

$93.22

In Stock

Qty

#19A

Air handler diagram

Service coil

Part #1585404-42NS

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

#7C

Air handler diagram

Heating elem

Part #B10374-70

Replaced by #B1037489S

$213.29 |

5% OFF Phone Price : $225.29

In Stock

Qty

Air handler diagram

Sequencer

Part #B12565-51

Replaced by #B1256558

$38.87

In Stock

Qty

Symptoms for gas pressure washers

Choose a symptom to see related pressure washer repairs.

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Why does my pressure washer spray too hard?

Main causes: faulty unloader valve, bad pressure regulator…

Why won't my pressure washer engine start?

Main causes: stale fuel, gummed up carburetor, engine needs tune up, throttle and choke controls need adjustment, bad re…

Why does my pressure washer's engine lose power?

Main causes: dirty air filter, stale fuel, clogged or dirty carburetor, bad unloader valve…

Why won't the pressure washer starter rope retract?

Main causes: broken recoil spring, damaged recoil starter…

Why is smoke coming from the pressure washer's exhaust?

Main causes: overfilling engine with oil, improper fuel/air mixture, choke system problems, dirty carburetor, engine nee…

Why does water spray out of my pressure washer's pressure relief valve?

Main causes: pump running for more than 5 minutes when the spray wand isn't being used, faulty pressure relief valve, ba…

Why is the spray from my pressure washer weak?

Main causes: insufficient water supply, clogged water inlet screen, clogged pressure hose, faulty pump check valves, stu…

Why won't my pressure washer mix in the detergent?

Main causes: using a high-pressure spray tip when applying detergent, clogged siphon tube, chemical injection system fai…

Why doesn't my pressure washer recoil starter work?

Main causes: damaged recoil starter, oil inside cylinder, locked up engine piston…

Repair guides for gas pressure washers

These step-by-step repair guides will help you safely fix what’s broken on your pressure washer.

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How to install a pressure washer chemical injection kit

The chemical injection valve draws detergent into the pump. If it’s not drawing detergent, use a repair kit to replace t…

Repair difficulty

Time required

15 minutes or less

How to install a pressure washer O-ring kit

O-rings seal fittings on the pressure washer pump. Damaged seals allow water to leak from the pump. Follow these steps t…

Repair difficulty

Time required

45 minutes or less

How to replace a pressure washer pump

The pump can be damaged by air in the inlet water supply or by chemicals that remain in the pump body after using the ch…

Repair difficulty

Time required

15 minutes or less

Effective articles & videos to help repair your air handlers

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

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Introducing new technical repair content that we’re developing for the Sears Technical Institute

Learn about Sears Technical Institute and the advanced technical content being developed for aspiring appliance techs.…

Model # A42-20 Official Goodman air handler with coil

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas pressure washers

Why does my pressure washer spray too hard?

Why won't my pressure washer engine start?

Why does my pressure washer's engine lose power?

Why won't the pressure washer starter rope retract?

Why is smoke coming from the pressure washer's exhaust?

Why does water spray out of my pressure washer's pressure relief valve?

Why is the spray from my pressure washer weak?

Why won't my pressure washer mix in the detergent?

Why doesn't my pressure washer recoil starter work?

Repair guides for gas pressure washers

How to install a pressure washer chemical injection kit

How to install a pressure washer O-ring kit

How to replace a pressure washer pump

Effective articles & videos to help repair your air handlers

Introducing new technical repair content that we’re developing for the Sears Technical Institute

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