- This topic has 32 replies, 6 voices, and was last updated 19 years, 1 month ago by
.
-
Posts
-
I bought this dishwasher in December 2006 to replace an older model SKT 2052 (bought in 1996) which had developed a few faults. The new model looks almost identical but has more programs.
At first it seemed to work all right and I got rid of the old machine. Then the new machine started to make a horrendous whining/grinding noise which penetrated the whole house. I wrote to Bosch and they sent a service engineer who agreed that it was noisy. He replaced the pump motor, said it should be OK and left.
But it was still noisy so I wrote again and they sent a different service engineer. He replaced the pump/motor and left. It was no better so I wrote again and they sent a senior engineer. He switched the machine on and we listened. The noise normally doesn’t usually start until the machine has been on for about ten minutes (Eco programme) after the heater has come on.
He agreed that it was noisy and tried various tests. He tried running it without the spray arm, tried it without the tray holding all the crockery, but still it made the noise. Then he tried it without detergent. (I normally use half a Coop dishwasher tablet.) This time it was not so noisy. He recommended me to buy some Finish dishwasher powder and try that. He said that the noise might be due to overfoaming. He will phone in a few days time when we have tried the Finish powder. If it is still noisy, he will order a new motor and pump housing.
Has anyone else had noise problems with this particular Bosch model or with Coop tablets? They worked fine in our old machine. Why should overfoaming cause a horrendous noise?
When I have tried the Finish powder I will post a further message to say whether it has solved the problem.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
woodey wrote:Why should overfoaming cause a horrendous noise?
Overfoaming results in a condition known as ‘suds lock’, the effect of which means the circulating pump is drawing in air through bubbles rather than water. As it is a gravity fed pump that means the motor races faster and the bubbles so intense they block the natural flow of water into the pump impellor housing.
Do not use tablets of any kind in a compact dishwasher, powder only! 😉
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
A friend’s Hotpoint Tabletop machine (a Bosch in disguise) does exactly the same thing, a screaming groan: sets your teeth on edge. It is caused by an excess of foam. In some cases the machine can actually leak wash solution around the bottom of the door.
Best to use powder and do not overdose; try and match the detergent dosage to the dirtiness of the dishes, decreasing the amount for relatively clean dishes.
As I’ve said before, the old style “Professional” powders are still available (chlorine based bleach) which have less likelyhood of creating foam. They might be available from a local wholesale shop, or Farmers’ Supplies shop, with the brand names of “Sun”, “Bryta”, and “Finish”.
The modern tablets have far too much detergent in them for a tabletop machine; they are meant for a full-size, 12-place-setting machine. Sometimes, there is even too much foam in slim-line, 8-9 place-setting machines.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Many thanks Martin and Trilobite for your responses.
It seems that my noise problem may be due to overfoaming. Last night I ran the machine with no detergent. The noise was acceptable and the dishes came our sparkling clean. Incidentally, Trilobite, which model was the Hotpoint with the screaming groan? Was it the same as our SKT 5102 or our old SKT 2052?
I tried to buy some Finish powder yesterday but our local Coop Shopping Giant stocks only Finish Powerball tablets (3 in 1 and 5 in 1), Fairy Active Burst or Coop brand brand tablets or Coop powder in lemon flavour only. I hate the lemon scent; that’s why I switched from powder to tablets in 2003.
Previously, I had used either Coop, Tesco or Sainsbury own brand powder but they all stopped selling unscented powder; they just offered lemon only. We had also used powder in our previous Colston table top dishwashers. (We don’t have enough room for a full size dishwasher in our kitchen.)
The SKT 5102 instruction book says ‘you can use liquid or powder proprietary dishwasher detergents’ but I never had any trouble with the Coop tablets in our old Bosch SKT 2052 so I assumed that it would be OK in the new machine. A separate ‘Summary of Instructions’ leaflet does say ‘The detergent dispenser is not designed for cleaning tablets as the dosage is not suitable for this appliance.’ But I only ever used half a tablet; the dispenser is too small to take a full tablet. Nowhere does it say that the reason for not using tablets is that they can cause overfoaming.
The new model SKT 5102 must have a different mechanism from the old SKT 2052. It seems it cannot tolerate too much foam whereas the old model was OK. I shall write to Bosch and suggest that they amend the instructions to make it clear that tablets are taboo because they can cause overfoaming.
I shall try further afield to by some Finish Powder or, failing that, Sun or Bryta. A local small shop sells Fairy Powder as well as Finish Powerball tablets. Does anyone know whether Fairy Powder would be OK instead of Finish powder?
If the machine runs OK with powder, my only concern then is whether the overfoaming might have damaged the pump housing or other parts of the mechanism. If so, should I ask Bosch to replace them before the guarantee runs out?
Finally, there seems to be a problem with the times dispayed on this forum. I posted my first message at about 11:45 am, not 9:48 pm. I find it hard to believe that Trilobite posted a response at 3:52 am. I’m drafting this message at 11:40 am. Will wait to see that time is posted on the site.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Forum clock is fine, might be settings in your ‘Profile’ click on small Profile link along top of page and set your time to GMT.
Jim.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Hi again,
The Hotpoint Tabletop 7892P, also has another model number: SKTHPA2GB. Bought around 2001. (I think the Bosch model at that time was the SKT5002).
Fairy powder was the detergent recommended for the Hotpoint, (said so in the manual), so it should also be fine for the Bosch.
Just bear in mind that all powders purchased in supermarkets, corner-shops, etc. tend to be of the modern enzyme/oxygen bleach formulation, which can still cause overfoaming if too much is dosed. Tea stains and tomato sauce stains have a habit of not always disappearing.
The old style powders with chlorine bleach tended not to foam up, bleached brilliantly, but they were sore on glassware and fine decoration. They are now known as the “Professional” style, and may be purchased in Cash & Carry’s, or Farmers’ supply shops.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Hotpoint Dishwasher
Many thanks Trilobite for info about Hotpoint 7892P. This model is not listed in the Hotpoint dishwasher brochure but I viewed the manual and found that it was like my new Bosch 5102, not the old 2052.
I bought a 3kg pack of Fairy powder from a local shop, weighed out 10g, put it in the dispenser and switched on the Eco programme. Result, no horrendous noise, almost no foam (I opened the door three times during the cycle) and a good clean wash. I should get 300 washes for my £4.99.
I noticed a faint smell of bleach when I opened the door. The label on the Fairy pack says that it contains ‘oxygen based bleaching agents’ and ‘enzymes, phosphates and nonionic surfactants’. It says it is a ‘3 times Active System – soak, scrub, shine’.
I will look out for some Finish powder in shops further afield but for now, the Fairy powder seems to have solved my problem.
Clock setting
Thanks too to Iadom about the clock setting. I clicked on my Profile button but could not find any way to set the time to GMT. What am I missing here? This message is being sent at 10.45 am.
My web browser is Safari on a G4 iMac and my computer clock is automatically set to the right time by the internet.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Go into your profile, scroll down to ‘Preferences’ next to bottom option, timezone should be set to GMT.
Or wait until the clocks go forward and you will be OK. 😉
Jim.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
woodey wrote:
If the machine runs OK with powder, my only concern then is whether the overfoaming might have damaged the pump housing or other parts of the mechanism. If so, should I ask Bosch to replace them before the guarantee runs out?
If there is any damage to the pump/other parts caused by the overfoaming then i doubt Bosch would do any replacements as your warranty covers you for mechanical/electrical breakdown of the appliance and your probs could be classed as customer mis-use .
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Hi Iadom
Clicked on the word Profile at the top of the page (what I did wrong before was to click on the Profile button at the bottom of the page) and found that, under Preferences, my time was set to GMT+10 hours. I reset it to GMT.
This message is going out at about 8.20 am
Many thanks for your help
Woodey
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Hi Iadom again
My message sent at about 8.20 was still showing the time 10 hours ahead of GMT. Clicked again on the word Profile and found that it was still set to GMT+10 hours so I reset it to GMT. Then found that there were two buttons out of sight at the bottom of the page, Submit and Reset. Clicked on Submit and got a message that my Profile had been updated.
Should be OK now. The time is now about 8.26 am
Woodey
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Who do you think you are Doctor Who. 😆
Glad you are back in the correct time zone. 8)
Jim.
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Since I bought the Fairy 3-in-1 powder I have tried some tests.
10g of Fairy does not foam anything like as much as the half-tablet (Coop). Better still, about 5g of powder (difficult to weight) gives even less foam but still gives good results. We always rinse off loose food before puttiing plates and dishes in the dishwasher.
I also tried 10g of some old Sainsbury powder (bought before they changed to lemon powder); same result as Fairy powder.
Finally, I tried 1/4 of a Coop tablet, about 5g (a whole tablet weighs 20g). It made a lot more foam than 10g of Fairy powder and was noticeably noiser in part of the cycle, but not the horrendous noise with half a tablet.
I’m still not sure why the old dishwasher SKT 2052 was all right with the Coop tablets. I don’t know whether the motor/pump is different in the new model. As one of the service engineers said, there are only two moving parts; the motor/pump and the spray arm.
The new model has a different shaped spray arm. In the old model, the spray arm was smaller and straight. The new model has a longer, curved spray arm.
This may mean that the new spray arm creates more foam which in turn causes the motor/pump to race, giving rise to the ‘screaming groan’.
That’s my theory. Anybody got a better idea?
Woodey
Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
I think you are right about the new curved spray arm creating more foam. The arm on the Hotpoint Tabletop machine has slots, as probably does your old Bosch.
Does your new Bosch have slots in the spray arm, or does it have round holes?
I’m inclined to think that the round holes give a stronger, more forceful spray pattern (they are present on my full-size Bosch bottom spray arm).
Whereas the upper spray arm has mostly rectangular slots (a gentler spray, perhaps?).Re: Bosch Dishwasher SKT 5102 table top model horrendous noi
Trilobite
Yes, the curved spray arm does have holes on the top surface.
I can’t remember whether the old spray arm had slots. I’m sorry now that I took it to the tip soon after we got the new model. I could have tried the old spray arm in the new model (if it is the same fitting).
With the half tablet there was still some foam (but no liquid) in the bottom of the dishwasher on the final (drying) part of the cycle. And with the tablet there was noticeably more foam during the first (Eco) part of the cycle than with the Fairy powder.
I shall write to Bosch suggesting that they put a warning notice in the instructions to say that certain kinds of tablets, even half a tablet, and possibly some powders, can give rise to overfoaming which creates a lloud noise.
I shall also write to Which? They gave they table top model a good report but said it was noisy. They may have used the wrong powder or too much powder. If they test it again with Finish or Fairy they may find that it is not noisy.
Woodey
- You must be logged in to reply to this topic.