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Hi,
Beko DFN28R22W. Pump wasn’t spinning so no water through arms in machine, pump just making a nasty noise. Removed, took apart and found graphite bearings worn badly, lots of impeller lateral play.
Replaced with a brand new pump from Beko. There’s now water coming through the arms but weak. You can hear the water trickling when it’s running, and opening the door quickly shows the water manages to rise two or three inches out of the spray arm holes. No blockages.
The pump motor has one live and neutral connector, plus another connector with 3 wires going to it, so I’m assuming it’s PWM controlled?
Duff new pump or more likely the main board is faulty? Visually mainboard looks fine, there’s 5V to one of the three wires and the remaining two signal wires go directly to the pins of an Atmega programmable IC on the mainboard. The live and neutral connections to the pump are good from the mainboard.
I was wondering if anyone else had encountered a similar problem following pump replacement?
Thanks,
Jamesthe pump will be a 3 phase unit driven by the board. chances are you can measure the motor to check the 3 coils are intact. if yes the chances are you only have a 2 phase output from the board
Dave
electrofix wrote:the pump will be a 3 phase unit driven by the board. chances are you can measure the motor to check the 3 coils are intact. if yes the chances are you only have a 2 phase output from the board
Dave
It is indeed 3-phase, and that is created by the PCB within the pump itself – I have the old pump apart. The mainboard doesn’t provide a 3-phase supply to the pump, though.
The mainboard provides a 240v live and neutral feed, a 5V DC feed, and 2 signal lines which come directly from the Atmega processor on the mainboard. Presumably the 2 signal lines are for speed control?
Found the problem. The valve system that controls water flow to the different spray arms in the machine was not moving due to an open circuit motor that Beko call “6 way valve synchronous motor”.
The valve disc that rotates via the above-named motor with a couple of holes in it which lets water pass from the pump to the spray arms had stopped in a closed position with one hole just slightly over a port to a spray arm, massively impeding flow.
The spray arms now have powerful jets of water coming from them.
It’s surprising Beko didn’t program an error code for failure of the valve disc to rotate, since there is an encoder wheel that turns in sync with it, operating a microswitch, which tells the machine the position of the valve disc. No microswitch on/off cycles could have been programmed to flag an error…
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