Question about Whirlpool GH7155XHS Microwave Oven

1 Answer

My whirlpool microwave humms even when i'm not using it

Posted by on

  • 2 more comments 
  • shuewebb Jan 04, 2009

    I have had the microwave unplugged for hours at a time because of the annoying noise and fear of fire or further damage. I had a hint that it might be a bad diode after the capacitor making the transformer humm. The only thing is that they said that the microwave wouldn't heat and mine still does. Any thoughts?

  • shuewebb Jan 05, 2009

    You're right, the microwave heated a cup of water without setting the timer or pressing start. It also had a burning smell when I took the cup out after about 2 min. The model is a Whirlpool gh7155xkt-0 serial#fgl4501727. This is great! What should I do next? If it can help I am an electrician and can test components with your help. Thanks again.

  • William Miller
    William Miller May 11, 2010

    If you haven't done so already, I would suggest putting a cup of water inside to see if it's possibly heating when it's not supposed to.

    If it's running when it shouldn't, that would be caused by a problem on the controller or a door switch or mount, not the high voltage diode.

    Sorry, but I forgot to ask your full model number from the tag / label on the unit..

  • William Miller
    William Miller May 11, 2010

    first thing I would suggest is a hard reset. Unplug the unit for a
    minute or so. Then plug it back in, set the clock and try again.

    If that doesn't work,
    leave it unplugged for maybe an hour. Then let us know if the hard
    reset does not fix it.

    You may have a bad filter capacitor on the control circuit board.

    regularly repair such control units for customers nationwide by mail
    for $39.95 postpaid in about a week with a one-year guarantee.

    Please reply back with
    your full model number from the tag so we can help you



1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Whirlpool Master
  • 9,098 Answers

It's almost certainly a shorted cook relay on the control board.

The relay has two metal tabs on top where the wires are connected.

There should be a "mini-manual" (tech sheet) hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, testing, and locating components.

At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

Be sure the oven is unplugged, then you can measure across the two tabs and I think you'll find the tabs are shorted.

A new board for this model runs over $150, but
we regularly repair such control units for customers nationwide by mail for $39.95 postpaid in about a week with a one-year guarantee.

Feel free to contact me directly (and please remind me of your full model number) for more information & help.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

William E. Miller

Posted on Jan 05, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Why does my whirlpool microwave turntable won't stop turning even when not in use?

There could be a defect in the door latch interface or the control board.

Aug 20, 2016 | Whirlpool Microwave Ovens

1 Answer

Microwave is not heating and making a loud humm. the turntable is spinning though. What is out on it.


Here is a tip that will help you to figure out what is wrong with your Microwave Oven....

Microwave Oven Troubleshooting Tips



Oct 14, 2010 | GE XL1800 1100 Watts Microwave Oven

1 Answer

My microwave makes a loud humm when turned on and does not heat the food. If I put in another mode, Meat, it sounds normal but after a mmin it starts to make the same humm. ???

You most likely have a bad high voltage diode. (Item F1 of link but labeled rectifier)

However... there are two other possibilties those being the High Voltage Capacitor (F2 of link above)
and the Magnetron istelf. (F7 of the link above)

More often than not the diode / rectifier is the problem.

Thanks for using FixYa.


Mar 19, 2010 | Frigidaire PLMV169DC Microwave Oven

1 Answer

Not cooking food even though it comes on

Check the power setting. You can tell if it is on a lower setting because it will cycle ( you can hear it humm lower for a short time then the sound is different and then it humms the same again. It is new.

Sep 02, 2009 | Oster 0.7 Cu. Ft. Compact Microwave

1 Answer

No heat when Microoven is turn on. GE XL1800 Spacemaker

If there is a loud humm the magnatron tube has gone bad. and some times there is no humm at all but i would say its the mag tube has gone out.

Jun 13, 2009 | GE JVM1850 1000 Watts Microwave Oven

1 Answer

Microwave wont heat

Test the high voltage capacitor, the rectifier diode.or the magnetron.

If it additionally does not spin and no light, then check also the door switch.

The diode and capacitors can br tested. The capacitor must be allowed discharge before testing, or you risk to get electrocuted, even if power is off. Capacitors can get discharged by shorting their two contacts.
Replace the magnetron if the checks and all of the high voltage component tests are good, but the unit still does not heat.

All locations, and description of this parts can be located using the diagram here: Counter top.

Parts must be tested to find out what is wrong.

Remember that microwaves are potentially dangerous devices if not repaired properly, the job must be done by a competent person.
A microwave energy leakage test must always be performed when the oven is serviced for any reason.

Regarding parts, contact the seller here to purchase parts. (here in UK).

Apr 04, 2009 | GE Spacemaker JVM1640SJ Microwave Oven

1 Answer

My whirlpool microwave oven humms

Yeah, that's fan which stuck in "on" state. However the root cause is in a control board.

Jan 25, 2018 | Whirlpool GH7155XHS Microwave Oven

1 Answer

Microwave no heat

The "HUMM" indicates a breakdown in the High Voltage Side. The loud "POP" was the breakdown. You have only four Components in the High Voltage side.

1. High Voltage Transformer. You can eliminate this as the problem. Why? If it was the problem it would have blown the line fuse, and would have given off a burned transformer smell.
2. High Voltage Diode. Usually will Burn or Pop when shorted, but will then OPEN the Circuit and there is no "HUMM".
3. High Voltage Capacitor.This is the Silver Can with the two terminals on top. It can SHORT internaly between the plates (the two terminals) and give the "HUMM".
4. Magnetron. This is my number one suspect. A SHORTED Magnetron.

Feb 03, 2008 | Kenmore 63652 Microwave Oven

1 Answer

Microwave not heating unless exhaust fan is on high

check the control unit and high voltage circuit, and megnetron, high voltage diodes, wiring and high voltage fuse etc.,

Sep 26, 2007 | Samsung MW1030WA Microwave Oven

Not finding what you are looking for?
Whirlpool GH7155XHS Microwave Oven Logo

Related Topics:

122 people viewed this question

Ask a Question

Usually answered in minutes!

Top Whirlpool Microwave Ovens Experts

William Miller
William Miller

Level 3 Expert

9098 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers


Level 2 Expert

228 Answers

Are you a Whirlpool Microwave Oven Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides