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Does anyone know the resistance and wattage of the cooling motor resistor?
The Stoves part number is 081731300 which has been discontinued!Thanks electronic, what is the source of your information.
The cooling fan on the oven had stopped and it was found that the series resistor had broken. Replaced the resistor and it lit up like a 100W bulb. I take it that the resistor is acting like a fuse where when the motor draws too much current the resistor exceeds it’s rated wattage and breaks?
I replaced the resister with two 10W 220ohm resistors in parallel so would have had 20W current rating but these have broken as too hot. The motor is rated as 0.310A 70W.
Any idea what the timer pcb does, does it just switch the negative to the other side of the motor?source of the information was a clear picture of the part on a suppliers website
resistor just slows the fan a bit to lower noise I assume.
The resistor you installed will get hotter and blow because its too large and if voltage drop exceeds 46v it will overload. Adding 2 resistors in parallel should have cured that but not if the motor is faulty. last one I saw did the same thing as motor was faulty
Dont know which line the timer board works on but all it does is allow the fan to run on after cooking for a given time
Dave
looks like fan motor may still available if its the plastic fan type.
think some early ones had a heavy metal fan motor and if yours is that one it could well be obsolete
so if you fit both it should cure your problemDave
Measured resistance of fan – 150 Ohm, from the current stated on fan it should be 742 Ohms.
Quoted price for a rewind – not less than £300.
The nearest EBM PAPST fan appears to be a R2S175-AB56-01 and the cheapest I can find it is £143.62 + carriage!
Anyone know of a cheaper equivalent or I’ll have to buy a new oven.you cant go by the resistance of the coil as its a coil so it has inductance that alters the coil resistance on an AC supply
That said from what you say its toast
Dave
OK, I thought I’d try the original fan motor with the 100 ohm resistor on the bench, ran ok and the resistor didn’t glow, current drawn was 0.25A. Connected to the timer pcb and it started up straight away (which shouldn’t happen) and it drew nearly 1A, resistor hot.
This lead me to believe it was the timer pcb that was at fault. New motor had arrived £180 from Radio Spares. Ordered new timer pcb from espares £30. Swooped timer pcb’s and connected old motor and it ran straight away drawing 1A. Swooped old motor for new motor and it didn’t run until you turned on one of the ovens or grill – correct operation. Swooped new timer pcb for old timer pcb and it still worked correctly!
So basically it was the motor that was faulty.What I cannot understand is why the old motor appears to work ok when NOT connected to the timer pcb and draws more current and runs all the time when connected to the timer pcb.
Anyone any thoughts, (both motors had the same resistance and I don’t have a way of measuring inductance)?
does sound odd
your still on the same supply with the same resistor and the only thing the timer board does is switch itonly one thing left is an earth fault on the motor as I guess you did not add the earth on the bench, but, if you have modern rcd’s it would trip your electrics
DaveThe fan did have a connection to earth as it was sat on its mounting bracket on the metal inside of the top of the oven.
Something I never measured was L – Fan body (Earth) 30 Ohms, N – Fan body 65 Ohms, L – N 100 Ohms. Still have old style fuses.
So why does the fan draw more current when connected to the output of the timer pcb as there is more resistance or is the 100 ohm resistor in parallel with the 30 Ohm L – E?yes shows you need to upgrade your fuse board. if the resistor had not acted as a fuse its likely the fan motor could get very hot. yes there should be thermal protection in the motor but its still a fire risk
An RCD device would have tripped long ago alerting you to the problem
RCD devices dont only protect against electric shock they also prevent a lot of electrical fires
Dave
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