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Old 30th Apr 2018, 1:58 pm   #1
TheDocker
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Default Goblin Teasmade 835B stops before tea's made!

Hello, Joined specifically about this Teasmade I bought second hand a few week's back.
It all works fine except that it stops boiling far too soon and only fills the teapot with enough for one mug of tea. It leaves about 800ml in the kettle as it switches off.
Its obvious that the base plate the kettle sits on is a switch. Is this adjustable in anyway to allow it to stay boiling until its a lot lighter? Otherwise, I'm thinking of what weighs about 700g that will sit safely ontop of the kettle.
Thanks.
BTW, this is a great site, wish I knew about it before I disposed of an old radio and tape deck a while back.
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Old 30th Apr 2018, 2:10 pm   #2
The Philpott
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Default Re: Goblin Teasmade 835B stops before tea's made!

If you click in the search box and input 'teasmade won't boil', there are a couple of threads which look closely related to your problem. You are not the first to experience this..

I would not recommend placing a weight on top of the kettle. (You probably haven't watched that scalding scene in 'Guest house Paradiso' !)

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Old 30th Apr 2018, 3:45 pm   #3
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Default Re: Goblin Teasmade 835B stops before tea's made!

Has the pot been replaced with a lighter one?
The switch on the plate has to take into account the weight of the pot plus the water.
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Old 30th Apr 2018, 5:24 pm   #4
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Default Re: Goblin Teasmade 835B stops before tea's made!

The switch under the teapot is a much lighter spring-loaded switch, purely to sound the buzzer and warn you if you turn the machine to AUTO with the teapot missing. It will work with the teapot empty, and with both the original ceramic teapot and also the later and horrid plastic teapot.

TheDocker's problem relates to the strength of the spring below the plate on which the kettle sits. This plate is hinged at one edge, and I wonder if the hinge has become stiff, maybe due to rust caused by spilled water.

The strength of the spring is fairly critical, as it's designed to cut off the power to the kettle element whilst the boiling water is being forced out by the pressure of the steam, at exactly the right time to leave just enough water in there to keep the element covered and prevent its boiling dry. Water still continues to flow once the element has cut off and the alarm has sounded, due to the stored pressure and heat in the kettle.

Other things you might like to check are the pressure relief valve in the kettle lid. If it's venting too much, water flow will be slow and may stop too early. However it does sound like you'll need to remove the base plate and have a good look at the spring below the kettle plate.

Good luck!
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Last edited by Phil G4SPZ; 30th Apr 2018 at 5:26 pm. Reason: Typo
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Old 30th Apr 2018, 9:45 pm   #5
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Default Re: Goblin Teasmade 835B stops before tea's made!

Is there any chance you could upload a video of it going through a tea making cycle to YouTube? It sounds crazy, but an experienced Teasmade user might be able to spot what's wrong; be it excessive steaming, early tripping or something else.

How much water do you need to have in the kettle to operate the platform switch? Remember to weigh the kettle lid first and subtract one millilitre for every gram, to account for the fact of the lid not being on the kettle while you are adding the water to it.

If you have electronic scales, they will even do the maths for you. Zero the display with an empty jug and the kettle lid on the pan. You can then weigh the water from the kettle in that jug without the kettle lid, so its weight will be subtracted along with the jug. Even cheap scales can read to the nearest 5 grams, but you'll be doing well to read a jug to the nearest 25 ml. And a millilitre is the same thing as a gram, as far as water is concerned.
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Old 1st May 2018, 11:43 am   #6
Mike Phelan
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Default Re: Goblin Teasmade 835B stops before tea's made!

A quick test is to slowly fill the kettle and listen to the click when the switch operates. This should be just before the water level in the kettle which has a marker on it inside below the lid.
In normal use, a little more water will fill the kettle to the marker.
If the switch needs adjusting underneath then it will operate well before the kettle is to the correct level.
We've used an 835 daiy since the 1970's!!
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Old 1st May 2018, 2:35 pm   #7
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Default

I will search those threads and No I haven't seen any scene in Guest House Paradiso, but will look it up, Thanks.

Hi, good question. The Pot and Kettle look like they belong together and sit on the base plates well, but it could be that it is a different one. Wonder if I can check this out somehow.

Thanks, I agree that the problem is with the baseplate/spring/switch and I need to brave up and carefully have a look. I thought I'd ask before taking it apart, just in the event that there was a recognised quick fix. Wish me luck.

Yes Mike, I did just that, and the switch clicks on when about 800mls of water is in the kettle. The capacity is about 1.20ltr so we're getting about 1 cuppa in the pot and fighting over it. I'll carefully see if I can take the plate off and do some tinkering.

Hi Julie, I may just see if I can video it in action. My basic CSE maths was enough for me to work out that the kettle when full is enough to start it boiling. As it empties in to the pot, I've measured that it leaves 800mls in the kettle, so its managing to empty about 300mls into the pot. It says it has a capacity of 1.20ltr, but I poored 1 ltr and it hit the full marker.
As was suggested by someone else, the kettle maybe a lighter replacement to the original, or by some other soul, that the springy thing underneath the plate may be corroded or rusted. It sounds right, nice strong clear click, so I guess I just need to try have a look see.

We've bought a house we're doing up and the kitchen feels miles away as apposed to the flat we're in. I guessed a teasmade would help stop the fight pushing one another out of bed to go make the tea. Of course, we're forgetting to bring some milk up to bed with us, so the pushing and shoving continues. LOL!
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Old 1st May 2018, 6:50 pm   #8
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Default Re: Goblin Teasmade 835B stops before tea's made!

Well, at least there's international football on this year. So once the tournament is over, there should be plenty of cheap mini-fridges around to keep your milk cold overnight -- if you don't mind a St George's or St Andrew's cross design!

Anyway, switching off with 800ml. remaining in the kettle suggests a problem with the platform switch -- excessive friction in the pivots, or too much tension in the spring. I'll do some tests later when I can get at my own Teasmade, and find its switching point.
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Old 1st May 2018, 7:58 pm   #9
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Default Re: Goblin Teasmade 835B stops before tea's made!

Thanks, I'm going to have a look at it tomorrow afternoon. If I find anything untoward, I'll share it here.
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Old 1st May 2018, 9:37 pm   #10
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Default Re: Goblin Teasmade 835B stops before tea's made!

OK, here are my measurements.
Code:
Kettle with lid: 798g.
Lid only: 84g.
Kettle full to tripping point, no lid: 1531g.
Kettle full to marker, no lid: 1889g.
From which I get the kettle without the lid weighs 714g., and enough water to come up to the mark weighs 1175g. = 1.175 litres of water in the kettle at the beginning of the boiling cycle.

It requires an additional 817 grams on top of the empty kettle to operate the switch. In normal operation, 84g. of that would be from the lid, so the kettle shuts off at 733g. of water = 733ml. remaining in kettle after boiling cycle. Probably a bit less than this in real life, since there will be some residual heat left to boil a bit more water and so push some more water up the spout.

That means only 442ml. of water leaves the kettle, and some of that is in the form of steam (although it expands about 2000 times, so 1ml. water = about 2l. steam).

But my Teasmade hasn't been used for a few years, so maybe its own platform switch is a bit stiff .....
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Old 2nd May 2018, 5:13 pm   #11
TheDocker
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Default Re: Goblin Teasmade 835B stops before tea's made!

That is some effort you have gone to for me, thanks very much.

The Spring is adjustable, though I found that the screw had had a daub of paint on it, probably to keep it in position. The nut supposedly keeping it in place is loose and I hadn't the tools to tighten it. So I caused a bit of damage to the screw threads by using pliers on the end it to keep it from moving and then used needle nose pliers to adjust the other nut.
Yes, the amount of water remaining in the kettle is about the same, and have kept that amount in, just enough to cover the element and enough for a couple of mugs of tea and a bit of a top up.
Having turned the nut quite a bit, I'm almost back to its starting point and it acts differently when I'm testing the 'empty' kettle on the plate - it turns off, but when I fill it and try it out, it won't turn off, though the slightest taps on the bedside cabinet and it turns off.
I got it working but a second time, it didn't turn off, so when I've more time, I'll turn the nut another turn.
Thanks again, folks.
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Old 2nd May 2018, 10:17 pm   #12
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Default Re: Goblin Teasmade 835B stops before tea's made!

There will be some trial and error involved. The tripping points would have been set in the factory using fixed weights to simulate full and empty kettles, then the nut painted to keep it from moving with the inevitable vibration. But now the spring has aged, altering the tripping points .....

Experimenting with mine, I found a lot of variation and a bit of a hysteresis loop in the switching action. The springiness even varies a bit depending how many times the spring has been compressed and released in a row (probably due to thermal effects; some of the work done compressing the spring ends up as heat).
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