Tefal Quick Cup modification

I purchased a Tefal Quick Cup back in 2007 soon after they launched. I initially thought it was a great idea to have 'boiling' water in measured quantities. Not long after, it fell out of favour at home here as the temperature of the water wasn't up to scalding teabags.
I measured the water temperature with a spirit thermometer, coming out at a chilly ~75 degrees C. Couple this with a cold cup and you have insufficient heat to brew tea.

The decision to modify it was simple - it either had to be assigned to the attic as a poorly designed fad-item or get placed in the WEEE recycling bin!

Warnings: I'm not including photos of the process here as anybody who tries this needs to know what they are doing, or face possible electrocution (no, I won't personally administer it). This process will void your warranty on your already useless Quick-Cup. I accept no responsibility for any damage caused or harm done.

Required:
T-15 star bit.
Flat-blade long shaft screwdriver (>15cm).
1x 10k ohm PCB mountable variable resistor.
1x 4k7 ohm resistor. (a 0.25W or mini-resistor should be fine here.)

Process:
1. Open the Quick Cup by removing the two star screws from the underside. Using the cord, lift the base away from the shell of the unit. The base is push-fitted into the body, so needs some force to free it.
2. When the base is loose you will note that the internal piping connects to silicon tubing via push-fit connections. Note the layout of the piping, pump and mains cord. Pull the base away from the pump to free it.
3. Disconnect the pump from the body and disconnect the power leads. The pump is not electrically polarised, so the two grey wires need not be replaced in the same position.
4. Looking into the body, locate the 5 locking tabs which retain the top button-panel to the body. Using the long shaft screwdriver, push the tabs outwards and then down to free them. Work on the tabs in a circular pattern to free the rear of the panel, then pull the panel off once all 5 tabs have been freed. This will expose the circuit board.
5. Loosen the PCB.
6. Remove the heater element and PCB from the body by withdrawing it through the bottom of the base. The heater element is retained with a silicon connection which slides open easily.
7. Observe the heater element connection with four cables running to it. The outer two of these (salmon coloured) serve to deliver power to the element, while the inner two (white) are the thermistor. The thermistor reads ~107k ohms at room temperature (~22 degrees C).
8. Observe the PCB track layout from the two white wires. One of these PCB tracks runs to a resistor (220 ohm I think) and the track is exposed and easily cut.
9. Solder the 10k variable resistor and 4k7 resistor in series on a suitably long twin-core wire to allow it to be installed alongside the PCB.
wire=--------| 4k7 |-------| 10k var |------------=wire

10. The variable resistor needs to be installed in series with the thermistor on the heating coil. This is done by soldering one end to the solder pad for the 220 ohm resistor already on the PCB and the associated solder pad for the connection block for the thermistor, again on the PCB.
11. Break the PCB trace between the resistor and the connector pad. Check the new connection with a multimeter - you should read anything from 4k7 ohms to 14k7 ohms.
12. Using a multimeter, adjust the variable resistor to near to 0 ohms.
13. Reassemble the unit *on the base*, but leave the top button cover off. Reassembly is not the reverse of disassembly.

• With the plastic body of the Quick-Cup aside, attach the pump to the water holder connector, noting the directional flow arrow on the body of the pump.
• Attach the pump to the silicon pipe which leads to the heater unit and push-fit this to the base.
• Attach the wiring to the pump and orientate the wiring so the connections point skywards.
• Ensure that all the wiring passes through the centre of the heater.
• Pass the plastic body down over the PCB and heater element and push-fit onto the base.
• Locate the heater onto the pipe which runs into the neck of the Quick-Cup. Fitting will seem loose as it's a silicon connection again.
  
• Fit the PCB in place, routing the new variable resistor to the side of the unit.
• Check and double-check your work.
  

14. The unit will now be fully reassembled except for the button-panel. Do not replace this just yet as it will lock in place and you won't be able to adjust the variable resistor.
15. *SAFETY WARNING* When plugged in, the PCB is LIVE and has exposed mains wiring. Assume that the variable resistor is also LIVE. DO NOT adjust the variable resistor when the unit is plugged in! Water and mains electricity do not mix!
16. Replace the water holder with a quantity of water which has been allowed to rise to room temperature and plug the unit into the mains.
17. Using an INSULATED screwdriver and one hand behind your back, carefully press the hot water delivery button on the PCB.
18. Measure the temperature of the water at the spout.
19. If the water temperature is too low, DISCONNECT the Quick-Cup from the mains, then adjust the variable resistor to 2k ohms. Retest the water output. DO NOT set the water higher than ~93 degrees (~2.5k ohms on the variable resistor) as the water will boil and splatter on exit.
20. Once the unit has been setup as required, Insulate the variable resistor with electrical tape and locate it safely in the upper lid of the Quick-Cup.
21. Replace the button-panel and also replace the star screws in the base.

Enjoy near boiling water from your Quick-Cup.

A modification of this would be to use a panel-mountable variable resistor and mount this in an accessible part of the quick-cup body. This will allow for temperature changes in the incoming water. I have found that water which comes directly from the tap (at ~7 degrees C) doesn't get up to temperature effectively. This may be a limit on the power of the heater versus the flow-rate of the pump, but I haven't tested this to be sure.