Queen coffee CQ MN-2 Heating element

[redwire]

Re: Queen coffee CQ MN-2 Heating element

The machine needs no fuse of its own - the branch circuit breaker 13A or 10A is expected to trip if there is a fault. The safety standard requires all the wires (power cord, plug, inside wires) to handle enough fault current to trip the circuit breaker, and not be capable of starting a fire inside.
The Coffee Queen of Sweden manual says nothing about safety approvals, even CE.


Here people grab a coffee on their morning commute, perhaps it's tea in the UK.
The 10kW is the 5-7 machines brewing non-stop at the drive-through for the morning rush. I realized that is a ton of electricity used heating water fast. Then there are the ovens toasting bagels and stuff.

[petehall347]

Re: Queen coffee CQ MN-2 Heating element

These kind of restaurant big coffee brewers used to be mainstream at Tim Hortons (BUNN), in the morning drive-through rush it must be 10kW+ of electricity used by them all. New coffee machines are now computer controlled and make yucky tasting coffee. You should see the programming menu.
So this one of OP's is nicely not super complicated.

that's like 42 amps .must have its own circuit .

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

These kind of restaurant big coffee brewers used to be mainstream at Tim Hortons (BUNN), in the morning drive-through rush it must be 10kW+ of electricity used by them all. New coffee machines are now computer controlled and make yucky tasting coffee. You should see the programming menu.
So this one of OP's is nicely not super complicated.

It's true what you said that someone poured something in the water tank my neighbor asked me to look at it because someone in his job accidentally poured some kind of farin then the machine died first when I tested it worked but then it just died. now thanks to all your help the machine is back up and running and i know the problem in case it dies one more time. but one last question : why is there no fuse on this machine ?

[redwire]

Re: Queen coffee CQ MN-2 Heating element

These kind of restaurant big coffee brewers used to be mainstream at Tim Hortons (BUNN), in the morning drive-through rush it must be 10kW+ of electricity used by them all. New coffee machines are now computer controlled and make yucky tasting coffee. You should see the programming menu.
So this one of OP's is nicely not super complicated.

[R_J]

Re: Queen coffee CQ MN-2 Heating element

I was too slow posting, like rewire said...
It may be sticking do to calcium buildup, or something is warped due to heat. Also check the force it takes to press the micro switch just in case it's actuator is sticking, not likely but worth checking.

[redwire]

Re: Queen coffee CQ MN-2 Heating element

I would replace the float only if it has water inside it. But they only sell the entire tank assembly 1204015.
It is more likely to have mineral deposits - lime, calcium, sand that is jamming it. Or someone dropped something inside, like coffee grinds, paper etc.
Flip it upside down! Try cleaning it with descaler (avkalkningsmedel).

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

Yes I think the water level switch or float is not working.
I am not sure how the water does not leak to the microswitch, there must be a seal or gasket. Something mechanical that might jam or get stuck.
pic from parts catalogue https://cdn.badcaps-static.com/pdfs/...5e66bfbe58.pdf

ok it's obviously the float that's malfunctioning. because now i've tried filling in water and i hear the float activating the process and it works but how long should it last ? i can't find the float itself in the link you posted.

[redwire]

Re: Queen coffee CQ MN-2 Heating element

Yes I think the water level switch or float is not working.
I am not sure how the water does not leak to the microswitch, there must be a seal or gasket. Something mechanical that might jam or get stuck.
pic from parts catalogue https://cdn.badcaps-static.com/pdfs/...5e66bfbe58.pdf

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

i`ll test and come back to you

[R_J]

Re: Queen coffee CQ MN-2 Heating element

Even if the boiler element was open, the Brew light (S3) should still light, If both thermal cutouts B5 and B4, mounted on the boiler are ok, and not open, I suspect B3 micro switch is either bad or not being activated.

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

There are two separate warming plates, do either of them work? There are also three lights, do any of them work? If none of the lights work and neither of the warming plates get warm, I suspect the main switch or the wiring going to the switch.
If the lights S1 or S2 light when the switch is turned ON, but the S3 brew light does not come on, check the micro switch B3, check that it is being activated. I believe the micro switch is activated by the water level, so if there is no water in the top reservoir, the boiler and the brew light will not work.

both plates get hot and their contacts light up but the brew light doesn't light up and it doesn't brew. the float that's suspect it's really tricky to it's connected to a switch underneath that might not get tripped when you fill it with water. after your explanation the picture of it all becomes clearer

[petehall347]

Re: Queen coffee CQ MN-2 Heating element

2300w element should be about 25 ohms

[R_J]

Re: Queen coffee CQ MN-2 Heating element

first it didn't work then on test it just worked but then nothing and I don't know what to look for plus I can't find a fuse anywhere

There are two separate warming plates, do either of them work? There are also three lights, do any of them work? If none of the lights work and neither of the warming plates get warm, I suspect the main switch or the wiring going to the switch.
If the lights S1 or S2 light when the switch is turned ON, but the S3 brew light does not come on, check the micro switch B3, check that it is being activated. I believe the micro switch is activated by the water level, so if there is no water in the top reservoir, the boiler and the brew light will not work.

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

Here is the boiler, check the resistance of the element, The thermal cutouts should read 0Ω.
What is the problem you are having with the machine?

first it didn't work then on test it just worked but then nothing and I don't know what to look for plus I can't find a fuse anywhere

[R_J]

Re: Queen coffee CQ MN-2 Heating element

Here is the boiler, check the resistance of the element, The thermal cutouts should read 0Ω.
What is the problem you are having with the machine?

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

On what? The heating element or the high limit temperature trip switch? If you do get continuity on both, things are good and it should work, unless one of the on / off switches or fuse is bad.

It must be on both to how high the temperature should be ? and now it doesn't work so you can't measure I leave some pictures of measurements. For V there is no current going anywhere but there is or I find no fuse.

[CapLeaker]

Re: Queen coffee CQ MN-2 Heating element

I get 26.1 ohms on all contacts if I have measured correctly

On what? The heating element or the high limit temperature trip switch? If you do get continuity on both, things are good and it should work, unless one of the on / off switches or fuse is bad.

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

The heater connections are at the back of the can.
The front of the can has what looks like two thermal switches. One is for temperature regulation and the other is a safety-limit (klixon). I might be wrong because I don't know the difference between AUTO/MANUAL operation of the heater, maybe it has two running temperatures.

I would measure resistance across the heating element, and to the can housing to see if the heater is not open-circuit or shorting to ground.

The two thermal switches should be normally-closed I think. The one on the right might have a reset button you can see, try push it down. But if it tripped then the left one is for temperature regulation and might be stuck on, so another problem.

I get 26.1 ohms on all contacts if I have measured correctly

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

This might be the service manual, if not it should be close.

thank you i have it but is not of great help

[bohaboha]

Re: Queen coffee CQ MN-2 Heating element

Hej CapLeaker this is getting a bit complicated.