[sapus]

Re: Hotpoint slimline DW doesn’t heat

Well, I removed the bottom tray, the circulation pump and the heater unit.

All very clean no sign of blockage or even scale on the heater element. Heater measures reasonnable 20 ohms (about 3kW). Flow switch operates fine and the thermal (I presume) cut-out on the side of the heater was on as expected.

Pump impellor looked OK, all blades present, and spins smoothly. The pump did however have slight plasticy rattle when shaken, and the back of the impellor blades had perhaps 2mm clearance (from memory).

Put it all back together and of course there was no change since I’d done nothing. I then checked the amount of water taken in, and thanks for that useful information “iadom”. It was 3 litres exactly. So I adjusted the pressure switch and brought it up to the required 4.2 Made no difference still low flow, cannot make it up to top spray bar.

(btw I was quoted between £33 and £60 by 5 or 6 internet based suppliers for the Press switch + carriage)

Checked spray bars, and all clear.

So I suppose it must be that pump impellor clearance; the pump appears to spin round nicely when powered up ? So looks like thats the end; I doubt a pump is peanuts.

Spare parts for a 7801 anyone ? got a good heater, and various switches etc ….

thanks everyone for the assistance

What does anyone think of Beko ?

[sapus]

Re: Hotpoint slimline DW doesn’t heat

I’ve given the resin matrix a good beating with a rubber mallet and its certianly nice and free now. When filling all the resin grains swirl around with no clogging of any kind, and look nice and clean. However I’m not convinced it was solid in the first place since I didn’t pay it much attention before beating it. As regards salt, the machine has never been used when the low indicator is visible. We’ve been quite religious about this, even though its not particularly hard round here.

I cannot see a fill tank on the back of the machine (behind the cabinet) only the matrix on the left. I would think if it needs one it must be incorporated into the matrix. I’ve noticed the fill passes through the resin up a column to the rear and then I loose track. The larger chambers to the rear and above the salt chamber always remain full at any time, and the salt chamber is mostly empty with only about 4cm of water in it with no apparent activity or flow here at all. Does that sound right ?

Anyway after all that beating nothing has changed, and it remains precisely as it started 🙁

I noticed on the Prewash programme it fills twice and drains without doing any circulating. It then fills a third time and begins immediate circulation. Not sure what the point of the 1st two cycles is.

Anyway still no decent flow to spray bars or any heat ??

I suppose I will need to start stripping it down further to look for a blockage. Not sure how to get the tray off the bottom. Looks like the machine has to go on its back, to allow the tray to hinge down ?

Any further pointers guys ?

[sapus]

Re: Hotpoint slimline DW doesn’t heat

Thanks for these thoughts guys.

My first thoughts were also a blockage of some sort just because of the low flow, and this in turn stopping the heater. I was checking out the pressure switch on advice from a professional repairer I know (180 miles away unfortunately).

btw George you are correct, I didn’t notice the terminals were not numbered in logical order. The middle one is the pole of course. 1-2 is NC and breaks OK 1-3 makes momentarily as I said. On at 50mm off at 51mm water. But I believe this maybe intentional because the on band seems to be adjustable. Not sure how this would function in the machine? See the switch at http://www.bitron.it/products/eldom/pdf/press-760-e.pdf

I notice you can see nicely into the metering tank. Any idea how the flow is supposed to make its way through the maze ?

You were quite right also George with the advice about removing the plug before charging about inside any electical gear, especially with water about. As a Chartered Electrical Engineer I know this only too well, but unfortunately little about the inards of the average dishwasher.

Once again any more details or theories would be much appreciated.

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