Tommee Tippee Perfect Prep Problems

The right formula for a poorly Tommee Tippee Perfect Prep Machine

The owner of this Perfect Prep machine had reported that it had not been used for a while, then filled with water, powered up and … nothing.

Make and model:  Tommee Tippee Perfect Prep

Cost of replacement:  £70

Cost of parts:  £3.69 (plus my time)

Hours spent on repair:  1 (plus testing)

Repair difficulty:  6/10

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FixItWorkshop, Worthing, June’18, Tommee Tippee Perfect Prep.

I’ve repaired a machine like this before and I already had a theory about the problem, which went like this:

  • Machine not used for a while; watery scale deposits built-up in machine
  • Machine filled with water, with possible air-lock present
  • Air-lock causes bubble in heater, causing it to temporarily over-heat, safety thermal fuses blow

Dead machine.

At this stage, it was only a theory, so the only thing to do was to start wielding screwdrivers.

A few quick checks revealed that mains power was not getting to the main controller in the machine, which indicated that the safety thermal cut-out fuses had failed.  There are two on this machine.  A quick test with the multi-meter confirmed that both had failed.

After some dismantling, both fuses could be removed from the wiring harness.  Fuses like these are not available from the high street usually, but they are readily available online.  The manufacturer had used crimps to attach the fuses to the wiring, but I decided to solder the new ones back in place.  Care had to be taken as the melting point of solder is very close to the thermal rating of the fuses, so I came up with the idea of using a damp cloth wrapped around the fuse while doing the soldering.  A bit tricky!

Both fuses replaced meant that the unit powered-up and worked.  Great.

However, I wasn’t totally convinced that an air-lock wouldn’t happen again so I looked deeper at the machine’s plumbing.  There appeared to be a kink in one of the boiler tube feed pipes, so I decided to cut some material away, to prevent the pipe restricting water flow in future.

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All back together, the machine worked well once again.

 

Tommee Tippee (not so) Perfect Prep

A formula machine is repaired in the workshop.

This fix was actually carried out during the summer, 2018.

A friend of mine brought over a broken formula making machine for me to look at.  It had been stored after their first child had out-grown it and since having another baby, it was now needed again, urgently.  Following a couple of years in storage, it was brought out, plugged in and after briefly coming on, it failed.  No lights, no hope.

These machines save time and effort by allowing water to be heated rapidly and mixed exactly with the formula powder, to produce consistent results every time, perfect for new exhausted parents in the middle of the night. So it was important that I got this working quickly.

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FixItWorkshop, Jan’19, Worthing, Tommee Tippee Perfect Prep machine

After removing the back, I was presented with an electronic control unit, some solenoid valves and a heater, plus some other environmental sensors such as thermostats.  The plug fuse was OK, so it was time to check if power was getting to the machine.  It wasn’t.

This machine features a couple of power control devices; two  thermal aluminium ‘can-style’ fuses in-line with the heater, plus a thermostat on the output of the heater itself (to regulate heat).  After testing for continuity, it appeared that one of the can fuses had failed.

These fuses are common across a wide range of appliances, such as coffee machines, fans etc and are cheap, just a few pounds.  It could be that a temporary air-lock in the heater caused a hot-spot and therefore that excess heat caused the 172 degree fuse to pop.  It was worth a try to replace it and see what happened.

I replaced the fuse and re-assembled.  After filling with water and powering it up, normal service was resumed.

Since I replaced the fuse, the machine has been in continuous service for many months, so I can conclude that it was probable that the over heating was temporary.

I created a short video to help others who may have similar problems with their machine.

Cost of a new machine:  £90.  Cost of repair: a few quid and a few beers.

 

 

Christmas blackout

A Christmas treat for me…

Christmas wouldn’t be complete without having to fix last years’ tree lights and this year was no exception.  It’s a tradition I look forward to and savour.

Gone are the days spending hours trying to find a faulty bulb, now due to the wide availability of cheap LED products, the thing that’s often likely to fail is the wiring, something which was much more unusual, a few years ago.  Manufacturers must make savings somewhere and I often wonder how retailers can offer new decorative lights, so cheap.  Compromises must be made somewhere I guess.

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FixItWorkshop, December’18, Worthing, Christmas Lights.

Being cheap, like a lot of things, makes them more disposable, which is a shame when things fail, often for trivial reasons.  This year’s blackout was caused by a couple of broken wires on the control box, which didn’t appear to have any obvious way to get inside.

We don’t like to be beaten in the workshop and sealed units and tamper-proof items are just seen as a challenge, rather than a deterrent.

Like many multi-function sets, the lights are operated via a control box with a switch, mounted in a plastic enclosure which appears sealed.  The fault was obvious here, just the main wire from the transformer had broken ‘flush’ with the control box, meaning that there was not enough wire either side of the break to re-join it.

The control box has no screws nor visible clips, holding it together, so it was time to break it open, using a small flat-bladed screwdriver.  The small section covering the wires snapped off cleanly, revealing several terminals covered in hot melt glue, annoyingly.  This meant that before any repair, the glue must be removed.  Several minutes picking this off with the screwdriver, revealed some conventional post terminals.  The fix was easy from there, just cut down the wire to make a new connection, remembering which way round they went, clean up the terminals and solder back together.  A little bit of fresh hot-melt glue to seal the connection and a bit more on the surface to be stuck together, and the cover was refitted.  I also fitted a little heat shrink to repair to reduce the chance of the cable from breaking again.

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As I had the soldering iron out, I also did a small repair to the control box wire to transformer plug, which had also broken.  It was a case of cutting back two sides of the break, soldering, isolating with a small amount of electrical tape and sealing with heat shrink.

Now that’s all done, Christmas can now officially start.

Cost of replacement: £ 5.00 up.  Cost of repair: 1 cup of tea, heat shrink, tape and solder.

 

Kaput Bosch AL1450DV Drill Battery Charger

An old Bosch battery charger gets a new lease of life.

These chargers often lead a hard life, working in dusty, hot and noisy conditions, so I guess many of these fail in time.

This Bosch unit is fairly common among Bosch DIY drill sets and this one had died catastrophically.  With the power applied, this one refused to give the slightest charge to a drill battery, once plugged in.

After some basic testing, I decided to change four components which would have caused the other to fail in a ‘domino effect’.  The cost of the replacement parts was just shy of £10, but definitely worth saving since second-hand units seemed to be changing hands for £40 on eBay, with their condition largely unknown.  The parts (two resistors, MOSFET transistor and diode/ transistor) were readily available online.

I recorded a short video to help others who might have a similar problem with theirs…