- This topic has 23 replies, 6 voices, and was last updated 9 years, 1 month ago by
.
-
Posts
-
Hi Everyone
Im looking for a little assistance into a tumble dryer fault please. The door filter light comes on, if you push start it comes back on again but then soon cuts out again with the red light on. So i have investigated and the following has been done.
Tumble dryer does get warm but keeps cutting out with red door light.
I dismantled door filter and cleaned any lint debris from filter and duct.
I removed condenser and cleaned under tap as per instructions found on line.
I removed right side of machine and found lint under the sensor by fan motor, removed this as thought this was problem, but machine still does the same.
Opened covering here as well and cleaned any lint from here, only minor.
Removed rear heater to look to see if heater had any lint, but hardley any found.Now starting to struggle 🙁
So tested the sensor on top of heater and the thermal fuse, thermal fuse has continuity and sensor has resistance circa 18k Ohm that reduces when warmed.
tested sensor by fan motor (NTC?) and again this has a resistance and reduces with warmth.
So I inserted a thermocouple close to the two sensors at top of heater to see what was going on and when you start machine it appears to turn heater on which rises to circa 250 Deg C this then reduces down to circa 30 Deg as fan blows air through. It tries again to heat and it goes to circa 340 Deg C but then stops and lights the door filter light.
Removed and reinstalled connections to pcb by selection knob but no different.
I guess the thing is cutting out because it thinks blocked by lint and overheating but sensors appear to be ok, can anyone help with spot where my thoughts are wrong please?
Thanks V Much
Kevin
Re: TDWSF83BEP Door Filter Light
Evening
ok, so based on some info elsewhere on this site I think my next course of action is to test the sensor resistance properly against known temperatures to build a table 25deg / 60deg etc.
I would like to know how this system works, is the machine supposed to regulate the power to the heater depending on temperature or is it just a relay or some switching transistor that crudely switches on / off to control temperature and thus the speed of response of the sensor is also important.
Thanks
Kevin
Re: TDWSF83BEP Door Filter Light
Is that machine not still under warranty as it looks to be a very recent model? Hence, little to no info on it as yet.
That being the case, you’d be better to look to get Hotpoint to fix it under the warranty.
K.
Re: TDWSF83BEP Door Filter Light
Unfortunately not.
When I get home tomorrow ill try and remove the NTC sensor on the heater to test against temperature.
Still like to know how the system is supposed to regulate heat.
Kevin
Re: TDWSF83BEP Door Filter Light
No idea, there’s scant info on those models as, so far as I was aware they were only used to replace dryers affected by the recall.
In any event they work as explained here:
http://www.ukwhitegoods.co.uk/help/fix- … hermistors
For refrigeration but the same basic principles apply.
K.
Re: TDWSF83BEP Door Filter Light
HI All,
So I removed the NTC sensor which is as follows:-
Manufacturer ELTH (that’s interesting as they make stuff for us at work in the fuel injection industry).
Type 279
T200
Date 11/15
Designation? 3111Set up was in our lab at work in the test oven with wires soldered to spade terminals, results as follows:-
25°C 12.4K
60°C 3.2K
70°C 2.4K
95°C 1.5K
100°C 1.05K
110°C 0.82K
130°C 0.6K
180°C 0.27KTest lead resistance 0.020K (insignificant)
Anyone know the specs and tolerance for this device? I can find some details on line for a whirlpool machine but it doesn’t state the type of NTC this suggests at 180°C it should be 0.1K, now normal resistors have tolerances circa 5{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} and this would be way out, but on an NTC i have no idea, anyone?
Specs found online for a whirlpool device
25°C 12.0K
60°C 3.0K
70°C 2.2K
95°C 0.1K (although this looks suspect value in manual)
100°C 0.8K
110°C 0.6K
130°C 0.4K
180°C 0.1KMy values seem shifted by circa 200 Ohms but this may be down to my device not being the one quoted in the whirlpool manual??
Thanks
Kevin
Re: TDWSF83BEP Door Filter Light
kwatt wrote:No idea, there’s scant info on those models .
Says it all really. 😥
Re: TDWSF83BEP Door Filter Light
Dont know much about them but what i can gather there is a reed switch at the condenser when the lower filter light comes it wont start until you remove and clean the condensor, i would assume there might be a reed switch also for the door filter, if there is a reed switch it might not be registering that the filter has been removed and cleaned. I also believe that they will not work if they are outside in a garage or similar they need to be in a normal household enviroment or they dont work.
Re: TDWSF83BEP Door Filter Light
Thanks Johnny but its not this, there is a proximity sensor for the condenser and machine won’t even start if this is not made, for the door filter that not the case, no sensor that i can find.
Doing some research on the net this Hotpoint is in fact a clone of the Whirlpool unit thats been made for a few years so quite surprised no information available. So far i still don’t know which sensor causes this light to come on or what the programmed logic is looking for. I’m wondering now if the reaction time of the NTC (on top of element) is suspect. From cold the machine cycles through the power up of the element twice before failing and putting on the door light, is the NTC not reacting fast enough to notify the programme module to turned off element and thus overheating. I’m assuming of course this is how the element is cycled (as no information coming to lite at mo) i.e NTc reports change in temp and should inform controller to turn off at a set temp then turn back on again at lower temp, or have i got this wrong and that it is just powered all the time?
I did run machine with door open (switch bypassed temporarilty for a fwew secs) and you can see the element glow behind the inlet to the drum and of course when it decides its too hot it turns it off also.
I also checked air movement, thinking that if not enough air movement then heater will get too hot, again this seems reasonable for the blowers (there are 2 on same motor) that are cycling, paper sticks and holds on inlet and is blown away from exhaust.
Cheers
Kevin
Re: TDWSF83BEP Door Filter Light
Hi
So i did some further work at the weekend, air flow all seems good with air being sucked in through the front condenser unit and a good flow out of the back grill that sits across top of water pump, so don’t think it s to do with blocked air flow. I found some service manuals on line (earlier models) and they do have some details on diagnostic modes and sequence of operations, anyone care to help with these?
For these type of machines Whirlpool / Hotpoint / Clones can anyone advise the start up sequence in regard of temperatures? Im guessing its looking for a temperature rise in a certain period of time but not sure! I have inserted temperature probes above heater and now in the exhaust NTC area as well. The Exhaust NTC area only fluctuates between 20 and 40°C is this warm enough?
Thanks
Kevin
Re: TDWSF83BEP Door Filter Light
The manuals you’ve found will not relate to this machine.
As I said before, in so much as I can tell this model was ONLY used as a replacement for the recalled dryers and not sold as such so, there is no information on them at all as yet as they should all be in warranty.
That’s why nobody can help you with it as nobody’s seen one and there’s no info or hardly even any parts listed as yet.
You will probably have no alternative but to contact Hotpoint.
K.
Re: TDWSF83BEP Door Filter Light
Thanks for your help, looks like i will have to keep trying on my own as Hotpoint’s answer will be to offer a service engineer.
New machines on sale here
http://www.electricshop.com/hotpoint-td … TM8P8HAQ#bCheers
Kevin
Re: TDWSF83BEP Door Filter Light
Yep they were being flogged on Amazon for a short time as well but, they’re all still in warranty as they were first seen last year.
K.
Re: TDWSF83BEP Door Filter Light
I have found out if you turn dial to 7 o’clock position and press the gentle button 3 times then press the start button this will let you into the diagnostics each press of the start button tests each component and at the end if one is faulty a fault code will be displayed.
- You must be logged in to reply to this topic.