• Please note, some of the links on our site are affiliate links (Learn More)

FIXED DV42H5200EP Samsung Dryer - Heating Relay not Switching On

Status
Not open for further replies.

ee293

Premium Member
Joined
Aug 16, 2017
Messages
2
Location
British Columbia
Model Number
DV42H5200EP
Brand
Samsung
Age
1-5 years
Hi,

I have a 2 1/2 year old Samsung Front-Loading Dryer (Model # DV42H5200EP) that has stopped heating. I tested the heating relay by probing both the blue and black wires (see attached schematic) on the heating relay individually between ground and measured 120VAC. I then measured the voltage difference between the blue and black wires at the relay with the dryer running on timer mode and measured 240VAC. The 240VAC indicated to me that the relay was not closing, so I inserted a temporary wire between the black and blue wires at the heater relay to bypass the relay and confirm that the heating assembly worked. When I ran the dryer with the bypass inserted at the heater relay, the heating coil lit up red almost instantly, so I know this works and is not the issue. I then tested the resistance of the thermistor by unplugging the dryer and disconnecting the harness from the control board and measured close to 10kΩ at at an ambient temperature between 23°C to 25°C which matched the resistance in Samsung's service manual.

This led me to then believe that the control board was the issue and I went and purchased the control board below:

Once the new control board arrived, I replaced the old control board with the new control board and still no heat. So, I again re-tested the heating relay and still see 240VAC between the blue and black wire, when the dryer is running. So this heater relay is still not closing either. I thought that the thermistor may be close to going, even though it tested fine previously, so I retested it and still measured 10kΩ. To completely rule out the thermistor, I then bypassed it using three different resistors (3.3kΩ, 10kΩ and 22kΩ) to represent different voltages going to the control board and measured the voltage difference across each while the dryer was running. The 3.3kΩ resistor measured approv. 1.3V, 10kΩ was 2.47V and the 22kΩ was 3.4V. However, none of those resistors were able to turn on the heater relay either.

Does anyone have a schematic for the Samsung controls for these dryers that they could send me or see something that I may have missed? I didn't think there was anything else that Samsung monitors to turn on the heating relay. The only other thought I had, was that the new control board is also faulty; however, I think this is very unlikely.

Here are some pictures of the dryer schematic in the service manual and how I bypassed the thermistor:

2.jpg

1.jpg
 

Tricky70

Member
Joined
Apr 5, 2018
Messages
1
Location
United states
Did you ever figure this out? I have a Samsung dryer that is not heating as well, I have replaced everything but the control board.
 

bigbuck

Appliance Tech
Staff member
Joined
Mar 19, 2015
Messages
1,800
Location
From Planet Mars
Sounds like the other op had a bad motor. Here is some information. The motor has two sets of contacts. One for the heating circuit the other for the centrifugal sense pin on the main board. It senses whether or not the motor is running by watching the state of that set of contacts. The first thing to do on a no heat is remove the top put it in a timed cycle, hit start and listen closely for the heater relay to close, if it does troubleshoot heater circuit. If relay does not close troubleshoot motor switch circuit, second set of contacts. Which means motor.
 

Attachments

  • Samsung Dryer Has 2 sets of terminals on motor 1&2 5&6 that has to close.pdf
    154.2 KB · Views: 1,341

ee293

Premium Member
Joined
Aug 16, 2017
Messages
2
Location
British Columbia
Yes, I actually figured it out the day after my original post. bigbuck is correct, the issue was that the microprocessor on the control board was never receiving the signal from the centrifugal switch, telling it that the motor was at full speed. Therefore, a close signal was never being sent to the heater relay to turn on the heating element. When I tested the resistance on the centrifugal switch contacts, I was getting a few resistances that didn’t match the manufactures suggested resistance, so I opened up the switch and found that the end contact on one of the metal switches had come apart.

Unfortunately Samsung doesn’t sell the centrifugal switch separate from the motor and I was unable to locate a place to just buy the centrifugal switch, so I had to buy a whole new motor DC31-00055G
 
Status
Not open for further replies.
If you feel that you have benefited from this site, and would like to show your appreciation.
Top