Question about DeLonghi De'Longhi Energy Star174; Approved 40 Pint Dehumidifier - DE400P Dehumidifier

Open Question

The pump is no longer working on my DP400 40 Pint dehumidifier. What should I do?

For 2 blissful months my DeLonghi DP400 40-Pint dehumidifier faithfully pumped the water into the drain.  Then about 2 weeks ago, I started to hear this beeping sound.  I discovered that the bucket was full, so I emptied it.  In 2days  it was full and beeping again.  I've searched high and low and cannot locate my owner's manual to determine how to get the pump working again.  I've searched on-line for a manual without success.  Can anyone help me figure out how to get the pump working and where to locate a manual on-line, so that I can return to that blissful state again?

Thank you!

Posted by on

  • Anonymous Dec 09, 2007

    My pump worked fine for about 2 years then stopped and makes a very loud grinding noise if I try to turn it on. I also cannot find my manual. Anyone have any suggestions?

  • Happy41 Feb 24, 2008

    I have a DeLonghi Dehumidifer CF80M. I was putting the tray back in after emptying and it got stuck! When I tried to put it back in again it was with some difficulty. It seems a small silver piece may be bent? Although it's working i.e. has power - there's no longer any water collecting.

    Can you advise?

    jan from sydney



6 Suggested Answers

  • 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


SOURCE: water bucket

If yours has a button/switch to turn on a pump, that will redirect the water to the drain. Sllee

Posted on Aug 01, 2008

  • 161 Answers

SOURCE: Bucket fills but unit will not stop dehumidifying.

probably a bad switch at the float assembly...check that out....probably going o have to replace that. check also for loose or disconnected wiring at the switch. let me know what happens

Posted on Oct 01, 2008

  • 2976 Answers

SOURCE: I have a 45 pint

It's for when you dump the bucket. You put the cup in to catch the drips while you're dumping it.

Posted on Jan 31, 2009

  • 37 Answers

SOURCE: 50 pint dehumidifier has drain hose connected but

safety switch is turning off the need to drain out the bucket more often....or put the drain hose into an actual drain....ive seen some people run a small plastic hose from the dehumidifier to the sump pump hole in their basement.

Posted on Jan 27, 2010

  • 43501 Answers

SOURCE: How do I empty my frigidaire 70-pint dehumidifier?

Here is a tip that I wrote to help people with just that dehumidifier problem..

Dehumidifier2_bing.gif Problem It shows Bucket Full


Posted on May 15, 2010

Add Your Answer

Uploading: 0%


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



Related Questions:

1 Answer

Need for a home dehumidifier for a 120 square meters space

normall you will need one pint of water for each 1,000 cubic feed of space in your . . example. 2,000 square foot with 8 foot ceiling would contain some 16,000 cubic feet. = 16 pint per day capcity to dehumidify the area.

God bless you

Oct 29, 2013 | DeLonghi DH100P Dehumidifier

2 Answers

I need the intruction manual for Delonghi dehumidifier model #DE40P.

Here is a link to the Owner's Manual, you're looking for. You can download and print the manual for future reference. Take good care of your model, perform routine maintenance, as required. As it no longer in manufacture. It has been replaced with a 45 pint unit. However, some parts your model are still available, if needed.

Hope this helped you.

Jul 11, 2011 | DeLonghi DE40P Dehumidifier

1 Answer

Does not dehumidify


There are many reasons why a dehumidifier will not work or collect water.

Here is a tip that I wrote to help people to figure out what is going wrong with their dehumidifier

Dehumidifier is running but no water is in bucket


Oct 04, 2010 | DeLonghi 40-Pint Dehumidifier Dehumidifier

1 Answer

Our delonghi de400p dehumidifier shows an E3 error message. Customer Service says its a sensor but can't tell us what sensor. Any help would be appreciated.

I have a 40 pint and a 50 pint that are very similar. The 40 pint has the e3 error. Experimenting with the 50 pint, I found if I disconnected a particular sensor I got the e3 error. That sensor is a little can with two black wires (smaller than a AAA battery but shaped like that). It is attached to the cooling coils so must be a temperature sensor. This is not the little circuit board sensor mounted in the middle of the radiator in a plastic box/clip thing.

I am now about to see that part to see if I can replace it.

Jul 09, 2010 | DeLonghi DE400 Dehumidifier

1 Answer

What should I set it at

If there is actual water in the basement, any setting will probably cause the unit to run. I would suggest setting it around 60%, and turn it up as you feel necessary. Hope this helps

Apr 01, 2010 | DeLonghi DE500P Dehumidifier

1 Answer

I need a manual for a 50 pint DeLonghi dehumidifier has a manual for a DE500P this may be close enough to yours

Aug 28, 2009 | DeLonghi DE500 50 pint Dehumidifier...

2 Answers

My 3-month old Delonghi 50 dehumidifier is leaking

Did you find the solution to your delonghi 50 pint issue? We have similar problem and No Manual - we are looking for manual too, any thoughts on where to find that too, please?

Jul 06, 2009 | DeLonghi DE500P Dehumidifier

2 Answers

DeLonghi 50 Pint dehumidifier DE 500P won't turn back on

If it is not responding when you try to activate the shutoff button and are still not recieving an acknowledgement that the bucket is full you may hav a defective shutoff button. Try contacting the Manufacturer and see if you can purchase just the button. This i a common part and the price is usually reasonable. If you feel very technical inclined you can remove the button and touch the 2 wires together simulating a closed contact. The dehumidifier should now acknowledge the bucket is full. If you recieve the notification then the button is bad. If you found this solution helpful please rate it.

Thanks - Tech101

Sep 04, 2007 | Dehumidifiers

Not finding what you are looking for?
Dehumidifiers Logo

Related Topics:

85 people viewed this question

Ask a Question

Usually answered in minutes!

Top DeLonghi Dehumidifiers Experts

dennis lewis

Level 1 Expert

3 Answers

Cindy Wells

Level 3 Expert

5299 Answers

Brad Brown

Level 3 Expert

16806 Answers

Are you a DeLonghi Dehumidifier Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides