Hoover Pcb Programming

[alanos313]

Hi,

I have a hoover DST10166PGB which has blown the main processor chip on the control board. I have fitted a replacement chip, but i need the flash file for the chip to reprogram it. It's an ATMEGA644. I appreciate that this repair is probably well above the scope of the average DIY repair. However, I'd happily settle for someone to point me in the direction of somewhere that reprograms Hoover modules? Ideally I'd like to find a Hoover engineer who is willing to reprogram the board for me, or just send me the raw .bin file so I can do it myself?

Cheers

Alan

[Whitegoodshelp (Andy)]

Did you find out what caused the chip to blow so it doesn't happen again? I'm not sure you'll be able to sort this although if you do please let us know. As far as I know Hoover don't sell the chips or replace them, manufacturers usually only supply a new board complete, which would normally come pre-configured or at least with a procedure to the configure the board via the machine itself.

[alanos313]

I blew the chip myself due to a schoolboy error. I was changing the heater, but was multi-tasking and working on two machines at the same time, however i hadn't unplugged the machine! Very silly (and dangerous) mistake. I accidentally touched the live heater wire to the NTC wire. I've been berating myself for this ever since. I have repaired the 4 surface-mount resistors that it took out, but it also blew a hole in the main processor chip. So I am confident that the board itself is fine.

When buying a Hoover control board, they can be programmed using an ICSP lead to a laptop, most of the 3-phase Hoover machines use the same main board. Hoover engineers have access to software (and firmware) to plug in and update the control boards as required... I don't have this equipment however I can use other programmers (eg Arduino, usbasp etc) to dump or rewrite the flash portion of the chips. I have done similar things with Dyson washing machines, and also have an extensive database of Hotpoint/Indesit firmware for EVO2 boards. Hoover is a bit of an enigma to me though (ironic since I began my white goods career working for them) because they use ATMEGA chips as opposed to PICs or EEPROMs for the program storage. I think I have come up with a way to get hold of the raw data for the machine now. I will post again in a few days after I have tried out my theory. Thanks for the reply, it's nice to know I'm not just talking to myself!

[Whitegoodshelp (Andy)]

That's proper hard core repairing I've never got involved in repairing anything on a board other than dry joints as appliance engineers have always been taught to just replace boards but some technically minded people have always played around sourcing generic resistors and parts for them. A lot of manufacturers are using laptops now which normally puts it completely out of the grasp of consumers and even ordinary independent repairers.

[jond]

Hi Alanos313, your post about reprogramming interests me considerably.

A year or so ago we bought a new Hoover Aristocrat AHD1410D to replace our 20 year old AEG that had been a brilliant machine until some trivial fault in the mechanical control packed up.

The new machine is pathetic at rinsing and all our towels etc. are somewhat caked up and are not properly soft in spite of the fact that we have supersoft water by virtue of using a Kinetico water softener. If I rinse a just washed towel in a bucket you’d be surprised how mucky and grey the water gets. When washing things like towels we have to use several rinse cycles to get things decently clean.

From reading the internet about this, especially a really informative thread on mumsnet, this is a now-ubiquitous problem, and like fug-emitting cars, the makers and suppliers of washing machines are all in denial about it, instead telling us how little water the machines use. A typical case of a wrong goal being chased. We buy these machines to get clothes clean!

It’s struck me that it should be straightforward for someone with the right knowledge to reprogram modern machines to make them use more water on rinse cycles and maybe have two rinse cycles. Do you think you could do that? I think there is a sizeable population of mothers who have children who react badly to incompletely clean clothes, so I think there would be a market of some sort for superchipping for washing machines. I for one would be interested.

I’m not ignorant of things like Arduinos and reflashing memory but it would be a significant exploration for me to try this. What do you think? Thanks for all and any help!

[Whitegoodshelp (Andy)]

Hi, I wrote about how rubbish modern washing machines can be at rinsing about 10 years back (why can't modern washing machines rinse properly?) It's all to do with prioritising water consumption levels over rinse efficiency without telling users the downsides.

The problem with reprogramming might be that they use pressure switch systems to control water levels, so when a predefined air pressure is reached and the pressure switch switches over it's likely to stop filling. They don't fill for a specific time which could be increased, they fill until the pressure switch switches over How a washing machine controls how much water goes in

[jond]

Hi Washerhelp,

Thanks for your reply. That's interesting about the pressure switches, as presumably one could fit a different pressure switch and get more water in the machine?

Jon D

[Whitegoodshelp (Andy)]

Yes in theory, but they are all calibrated to receive the air pressure from different length and even different gauge tubing with different pressure chamber designs so you could get underfilling or overfilling. Modern pressure switches have changed to work with magnets and coils so potentially it might be possible to reprogramme something as I suspect they stop filling when a particular reading is sensed as the magnet moves through the coil but to be honest I haven't given it much thought as modifying isn't something of particular interest. One simple thing to do if not done already though is to carefully read the instruction book in case there are options to use more water on rinses.

[jond]

If pressure switches are involved, then one could connect a U tube with say oil ( more viscous than water and it won't evaporate) in it to the atmosphere side of the pressure switch. If it's fitted with the two sides of the U tube unbalanced then it can add a bias to the pressure switch, so one could make it open at a higher or lower pressure as wished. Project number 357.....

[Whitegoodshelp (Andy)]

No because the air would get trapped and the pressure switch would never switch off. The air has to go up and then release.