DeLonghi ESAM 6750 : Water circuit empty ...

Howdy,

I'm new here, I've been using SAECO KVMs for years to keep mine alive ... then I got fed up and switched to the 6750. 5 years warranty at the department store, 2 times repaired in the time and now after 7 years my third case (which I find actually quite good):

When switching on, sometimes also only at the reference test, it only hums quietly as if it wanted to, but could not and then the message appears that the water circuit is empty. In the beginning this was not the case, because water came out immediately when the spout was plugged in and the OK button was pressed ... in the meantime it was really empty. It still goes from time to time... but I would like to repair it permanently. After the first appearance I manually decalcified the spout and the error was gone for a few weeks. Now it's back.

Unfortunately I didn't find a watercourse plan for the 6750 and I didn't find the corresponding threads for the machine via search. I'm thankful for tips concerning graphics and hints which spare parts I have to order exactly.


thank you
,wish everyone a handful of beans in the


bodie

tank

The water circuit always starts at the tank and the first thing to look at is the transparent filter behind the side panel. If it is dirty, remove it and rinse against the normal flow direction until it looks clear again. If it is not the right one, check the hoses up to the pump...

It could be a calcification in the system, but maybe it is the pump itself.
You could disconnect the pressure hose behind the pump from the rest of the pipe system and check if the pump
delivers
water when it is switched on
.

QUOTE (Guest_Ingmar @ Saturday, 08 August 2020, 22:53 h)

The water cycle always starts at the tank and first look at the transparent filter behind the side panel. If it is dirty, pull it off and rinse it against the normal flow direction until it looks clear again. If it is not the right one, check the hoses up to the pump...

Thanks for the answer!

I removed the side and back panels, took out the water connection of the tank, cleaned it and put it in as it was. The tank could not be pushed in effortlessly to the stop, so I removed lime from the surfaces and took away some plastic in front of the microswitch so that the tab would fit better to the lever.

Then I removed the 90° plug to the water hose in the machine from the tank connection to the flowmeter including the hose, the flowmeter and the next hose to the pump, cleaned it and put it back in. There was a lot of black dirt in the 90° piece, bah! I replaced the membrane switch on the pump and then reassembled everything again.

In test mode, the two valves click happily and on command, sounds healthy so far. The pump, however, does nothing at all except a super-short electrical hum. Definitely not moving.

The crazy thing is, when I turn on the machine in the morning I usually (1) get coffee without any problems. If the box stays switched on for a longer time, the message "water circuit empty" (2) appears and then it doesn't go away again. Possibly I have here 2 problems that overlap ... or it is haunted somewhere in the electronics (that is guessed).

to (1): If I have a problem in the morning, he says "Insert tank". If I push the tank firmly into the bottom front and/or knock on the side wall behind the tank, it usually works again. The pump starts up and there is coffee.

to (2) In this situation the pump does not start anymore. The machine wants to pump hot water, it also heats, but at most something boils out but without the pump's involvement.

How can the pump run sometimes and sometimes not ... I don't get it. At the moment there is no water in the pressure hose that goes to the pump, there is no water in the feeding hose either. So the water circuit is really empty and the pump does not pump.

QUOTE (Steinhaeger666 @ Sunday, 09 August 2020, 10:30 am)

It could be a calcification in the system, but maybe it is the pump itself. You could disconnect the pressure hose behind the pump from the rest of the pipe system and check if the pump delivers water when it is switched on.

Thanks also for this answer!

So, I have a partial success.

The pump was actually not good anymore. The issue of "empty water circuit" was solved by installing a new pump and replacing the silicone hoses from the tank to the pump. My machine didn't have the filter, respectively it is installed in the tank nozzle, not in the hose. I have now added one in the hose, because the hoses were already clogged ... kA where the stuff came from.

I still have a remaining problem, but that alone paralyses the machine: "Fill the tank." If I jam the tank with a good taste then it beeps and the machine runs mostly. Sometimes I have to drum a little bit on the right side so that it beeps and runs. I removed the micro switch on the top of the tank (ESAM 6750) and measured it, resistance was normal 0.4 Ohm and nothing seemed to be broken. It clicks also well-behaved with gentle pushing in of the tank.

Any idea what other parts are involved in such an error message?

A pity, apparently few 6750 owners here in the forum. Nevertheless ... if someone stumbles by I will answer myself, then hopefully sometime here is the final solution of my overall situation.

In the meantime I drank a lot of coffee (sure..) and never again had an empty water circuit. So I assume that I had two different problems at the same time. That's bad luck. I still have the "Tank Fill" message, but I tried something and read around in forums.

Yesterday I replaced the microswitch in the top back and checked the spring loaded lever mechanism. The lever has no cracks and is not bent or anything like that. I measured the old switch and according to a forum post from somewhere there I measured the correct 0.4Ohm. Also the exchange did NOT bring anything, so the old one was ok.

Next I will take a look at the float today, and remove the reed sensor (white little thing screwed to the side wall on the inside of the machine next to the water tank), clean the contact surfaces and reinstall them as flat as possible on the wall. Apparently this is a kind of magnetic field sensor that senses whether the float in the water tank is floating on top or not. My float is on top when the tank is full, so it works, but I have read that these things can lose their magnetic force, become stiff or stick because of dirt.

I have no idea how to re-magnetize the magnet, but if all of them don't work, the only thing left to do is to buy a new water tank.