Putting it back together

With all the requisites for brazing to hand I thought that I had better make a trial attempt before having a go at the real thing, so I cleaned up a pair of nails that I found rolling around the shed.

The first attempt was a complete failure. I hadn't secured the two nails in place and, being round, every time I brought the brazing rod in they rolled apart, doh! On the second attempt, after wiring them together, I got a bond. But the distribution of the braze was not even across the two nails (the smaller had more) indicating that I hadn't got them both to the right temperature. This was confirmed when I took them to A More Experienced Man who promptly twisted them apart and said "that hasn't worked." However I thought I had got the hang of it, mostly.

The brazing process for the fireguard took another 3 sessions, each faster than the last. I learnt a few things on the way; that the workpiece had to be red hot; that if the flame was showing green tinges I had the brazing rod too close to the flame; that lots of flux was a good thing; and that it was best to heat along the thick rod and move the brazing rod in behind the torch flame. In then end I got the thing together even though some of the mesh wires got a bit distorted and some of the joints were, from my reading, far too far apart. Fortunately the fireguard isn't structural so my crappy joints won't be overtaxed and overall it doesn't look too bad.

Brazed and unbrazed workpieces

Brazed and unbrazed workpieces

Immediately after brazing I doused the hot workpiece under the hose and removed as much of the scale (ie flux) as possible with a wire scratch brush and a pair of pliers. I followed that up by grinding back any excess braze with a Dremel grinding stone and more brushing with a steel wire attachment on the Dremel to remove the last of the scale. Finally I used& emery cloth and wet & dry paper until I had everything smoothed out and any burnt paint sanded back. I gave the whole thing a white spirit wash and it was ready for painting.

I hummed and harred about which paint to use but in the end I settled for engine enamel because it has a gloss finish and the fireguard isn't likely to get massively hot (the enamel is OK up to 150^oC). Two coats of that and job done.

Painted re-worked fireguard

Refitting the brazed panels was straightforward and everything came together as planned. The overall cost was quite high, but 60% was for tools and of the remainder probably only £10-15 of consumables were actually used. Not too bad for a custom fit piece.

Re-assembled fireguard

JOB DONE.

Time taken : A week (excluding delivery time)
Cost : £102.98 (including £59.62 for tools)

How to braze

As usual when researching a new topic, the first port of call was Wikipedia. Thirty minutes of reading later, crimey! Talk about complicated.

After a strong cup of tea and some cogitation it seemed that the easiest route would be to torch braze with either a silver or brass alloy. However I was going to have to do a lot more reading before I could make any progress. The web was, as usual for practical technical subjects, a bit patchy. But a YouTube search did at least give me some examples of what the process looked like. Unfortunately I couldn't find enough of the right sort of information to make decisions about which brazing system to use and what I would need to get hold of to carry it out.

In this situation wise words are "if you want to save a week in the shed, spend a day in the library" and I came up with two books on the subject, Soldering and Brazing by Tubal Cain (Workshop Practice Series #9) and Brazing and Soldering by Richard Lofting (Crowood Metalworking Guides).

Brazing and Soldering by R Lofting

Soldering and Brazing by T Cain

They were both useful, covering the subject from slightly different angles but broadly were aimed at the practical aspects of the process. Once read they allowed me to work out that I could use bronze brazing and a propane torch to get the job done. Thus avoiding the expense of silver-based alloys and kitting out with multiple gas cylinders for a process that I might not need again.

The shopping list for the job involved

• PPE (safety specs - already had, a pair of welding guantlets, and a fire extinguisher - hose pipe)
• Consumables to prep the workpiece (Dremel flap sanders and some soft iron wire to secure everything in place)
• A brazing hearth (a donated trolley and some old fire cement as firebricks)
• Requisites for the brazing (a blow torch and some propane gas)
• Brazing consumables (bronze brazing rods and sifbronze flux - obtained a small quantity together on eBay)
• Something to process the workpiece afterwards (quenching trough - hosepipe again, wire brush - already had, Dremel to grind back any excess braze, and wet & dry to clean up the workpiece).

So while the orders arrived I cleaned up the surfaces to be brazed, removing any paint and taking the metal back to bright steel, in preparation for putting the pieces back together.

Pot stove guard

When we moved into the house the kitchen had a pot stove in the fireplace where there had probably been a small cooking range. It's nice enough decoratively but as the chimney is functional I spent some time sorting out the register plate in the fireplace and getting our local sweep to come in and clean out the chimney. He told us that the lining of the chimney had decayed and that we should have it replaced or a stainless steel liner fitted.

As the roof on this part of the house required replacement we had the roofer drop a liner down the chimney at the same time as it was being re-roofed. A bit more time was spent converting the register plate into a closure plate. Basically this meant fitting a hit-and-miss vent to stop any moisture building up in the now enclosed space between the liner and the chimney walls.

Now the thing was ready to fire again, and was a few times, but I just couldn't rely on one of the Tykes not running into it while it was hot (and still can't even as they approach teenage years). The solution was to take the wire cage fireguard from the living room which had outlived its usefulness (as the Tykes are now old enough to know not to mess with that fire) and move it into the kitchen.

The guard had been made in two halves and is about five foot wide and a foot deep, with the centre rising in an arch, The rearrangement was obvious, simply swing the two ends together forming a cage that was longer than it was wide with the open end and the tops of the arched segments at the rear. Then push the reformed cage into the alcove round the stove.

And it even worked; sort of. Unfortunately the stove pipe stopped the two halves of the fireguard from lying next to each other. Meaning that the whole thing was sort of scissored round the stove and pipe, the clips that were supposed to join it together couldn't be used and the whole thing couldn't be fixed in place. Generally a less than satisfactory situation.

After using it like this for a while (read a year or so) I decided that as part of the kitchen MRO process I was going to sort it out. A bit of metalwork was going to be needed, my skills in which haven't advanced since the second year of comprehensive (ie they are still nil).

I decided that I could cut out the corners and flip them over to create the required rebate for the stove pipe. As my spatial reasoning is appalling, out came drinking straws and scissors so I could confirm that if I made the cuts the ends would come back flush to each other. Then it was just a matter of making the measurements for the rebate size needed to fit the guard round the stovepipe and out with the Dremel (with a slight side-step to buy a new tool, a set of cheapo measuring calipers to get an accurate diameter on the stovepipe - these were OK after I had ground the ends square). I used a protractor to mark out the cuts as near as possible to 45^o and made the cuts on the frame wire first to minimise any movement during the cutting process; followed by detaching all of the mesh wires close to their attachment point on the frame wire. After this I ground back the remnant stubs of the mesh wires from the detached frame wire piece and voila! It was able to flip over as required and formed the correct size rebate.

One section of cut fireguard

Only the small matter of how to rejoin the pieces remained. I could glue it but I was pretty sure that a) it wouldn't last and b) the heat from the stove pipe might melt it out the first time the stove was lit.

So a metal joint was probably a better bet. Welding then? A bit of reading lead me to the conclusion that I was going to have to buy a lot of kit and that I had cut the guards the wrong way (the welding process prefers a butt joint to a chamfered one).

The next option was soldering/brazing. I was still going to have to buy some kit, but the joint was cut correctly for these processes at least. For this application there wasn't much to choose between them. The stovepipe gets too hot to touch but is not likely to get hot enough to melt a solder joint. Brazing is stronger but a bit more tricky to get to work. However as I haven't done any brazing before this is what I went with.

Clothes airer repair

Moving along from the oven the next piece of kitchen equipment in distress was a clothes airer; a pulley type that hangs from the ceiling. The issue here was that the cleat that the rope was fastened to in order to keep the airer at ceiling height had come away from the wall.

Bodged plasterboard wall cleat

Broken pulley airer

As you can see I had just bunged in a couple of Rawlplugs to see if it would work - it didn't. OK so now I have to replace the fittings. There are a few options for fixing into plasterboard,

Spring toggle, hollow wall anchor, self-drive and nylon toggle plasterboard fixings

Given that the cleat is going to be experiencing quite a bit of lateral force and that the load is not static (as the fitting will flex when the airer cords are applied and released) a fixing that is able to spread the load over a wide area rather than just on the edges of the fixing hole would seem to be preferable.

This narrows the field to spring toggles, GripIts or metal cavity (or hollow wall or interset) fixings. Relative data on the load carrying capacity of each was difficult to find but the metal cavity fixings looked like they were the strongest (9-18kN load depending on plasterboard and fitting size; p.81 Rawlplug Lightweight Fittings Guide). The toggle fixings were going to need a large hole cut to get them in, one that the base of the cleat was not going to cover. The GripIt fixings also needed a large hole cut and it was going to be difficult/impossible to get two in close proximity. For that reason I decided to use intersets.

The first issue to solve was that the countersunk holes in the cleat were too small to take the M6x60mm fittings. Out came the drill press and the holes were enlarged slightly to accommodate the M6 bolts.

Countersunk holes in cleat drill out to 6mm

The next issue was that, because of the close proximity of the two holes in the cleat, as the interests were tightened the closest legs would interfere with each other. Removing a leg from each of the interests with a Dremel cutting disc remedied this problem.

Cleat with pair of fettled intersets

The holes in the wall that had the Rawlplugs torn out of them were large enough so that the cleat assembly could be tapped straight into place and the interests tightened

Repaired wall cleat

Operational pulley airer

JOB DONE.

Time taken : 2hr
Cost : £0.92 for intersets

Can I do it myself?

Before I posted the write up on the second fix on the cooker (repairing the broken button) I had to try and work out whether I had done anything illegal or not.

Even before I started the repair I had to think carefully about whether taking the top off the cooker would affect any of the gas tight joints, as that is obviously a safety risk, and this was the main reason for posting on ukwhitegoods.co.uk. I will freely admit that I was not read up on the relevant gas safety legislation but as I was not going to be altering any of the joints I felt the risk of a leak was negligible. If you follow the link to the forum you will see that I got one 'knee-jerk' response to my request for information which was that I "must" have a Gas Safe engineer look at it. "Must" is quite a strong word in regulatory documents meaning that you have no choice about compliance.

A trip was made to the Gas Safe Register home page for more information. The Gas Safe Register is quango run by Capita for the HSE and they are responsible for licensing engineers who work with gas appliances. They also publish a factsheet that details who can do what with gas appliances. Therein lies,

What gas work can I do myself?

The definition of gas 'work' is quite wide ranging but you can perform the tasks set out in the user's instructions, (provided by the appliance manufacturer) that are intended for the user to carry out. This would not be a breach of the law. The law allows you to replace or adjust any component or control that is designed to be operated, or replaced by the gas consumer e.g. a cooker tap control knob. However you should not do anything that involves disturbing the gas carrying components (such as the gas supply pipe) or that could affect the combustion process (such as removing the combustion case of an appliance — see Can I take the case off my gas appliance? below).

As I'm not going to be affecting the gas carrying components and the repair is to something that is to be operated by the consumer, it looks like I'm OK. However I am going to have take part of the "case" off the cooker, ie the cooker top. So reading a bit further down gives

Can I take the case off my gas appliance?

It depends on whether the case is purely decorative or whether it is an integral part of the appliance.

Decorative casing: These cases can usually be removed by the consumer e.g. can be lifted off or are hinged panels and do not need to be unscrewed. A decorative case can be removed safely by the consumer or anybody else remembering to follow any manufacturer's instructions and warning labels and making sure you have safely isolated any electrical parts.

Integral casing: Many appliances have cases, which in addition to being decorative, function as a part of the combustion circuit and form an important seal around the gas carrying components e.g. burner, combustion chamber, gas valve etc. If removing the case involves undoing a number of screws, this normally means it is a functional case and it should not be removed by the consumer or a person who is not Gas Safe registered.

Well there are definitely screws involved so perhaps I can't do it. But on the other hand there is no seal on the gas burners on a cooker top as they are external. Unlike the authors of the fact sheet I don't believe the presence of screw fixings magically imparts a meaning. The important words here are "Many" and "normally," basically the case may or may not be functional. Is it?

You could argue that the cooker top is screwed down to stabilise the burner and valve assembly so is integral. On the other hand all the gas-tight seals on the burner and valve assembly must have been made before the cooker top was screwed down as there is no access once it is in position. Most likely the cooker top is screwed in to place in order to provide a stable foundation for the cooking utensils placed upon it.

In the end neither the Fact Sheet nor the pronouncements of the Gas Safe Register are law; the statutory instrument covering the work is The Gas Safety (Installation and Use) Regulations 1998 No. 2451, which states,

(6) Nothing in these Regulations shall apply in relation to—

(a) the supply of gas to the propulsion system of any vehicle or to any gas fitting forming part of such propulsion system;

(b) the supply of gas to, or anything done in respect of, a bunsen burner used in an educational establishment; or

(c) work in relation to a control device on a gas appliance if—

(i) the device is intended primarily for use by a consumer of gas; and

(ii) the work does not involve breaking into a gasway.

So as the work is a repair to a control device intended for use by the consumer (ie a button on the front of the cooker) and I'm not breaking into the gasway as far the law is concerned I seem to be OK. Note the difference in language between the Factsheet and the Statutory Instrument, "disturbing" and "breaking into" don't quite mean the same thing. When I moved the cooker out from its alcove I disturbed the gas hose from rest but as it's designed to be flexible& I didn't break into it.

So it looks like I'm safe from prosecution (at least for now).

Oven Repair II

OK, so the top oven gasket has been fixed (twice), next job was to repair/replace the button that had broken off the control panel on our Zanussi ZCG551GXC cooker.

Broken middle button on control panel

This meant getting under the hood, so to speak. For repairs to anything this is not always a straightforward process as you need to find and remove all the connectors holding the item together and often it takes a specific twist or order of disassembly to successfully to separate the pieces without damaging anything.

For white goods there are a few places to ask for help that often turn up trumps. Whenever I get stuck the ukwhitegoods forums are often helpful, but not in this case unfortunately. Other places to try are DIYnot or the Screwfix forums, but being more general they are often less helpful for this type of question. So it seemed that I was basically on my own with this one.

First task was to pull the oven out from its alcove, dislodging one of the feet in the process (this would have been part III if it hadn't just screwed back into place). Then another bucket of soapy water was made and I cleaned as I went along.

If you are reading this with a view to take apart your own machine, please for the love of Mike make sure you have disconnected it from the power before you start poking around in it. What follows is what I did, the description may include stupid and/or unsafe practice. I'm not liable if you repeat this and stuff something or yourself up. Nuff said.

At the back of the machine there were two T15 Torx self-tapping screws on either side of the hinge assembly for the glass lid that came out.

Location of cooker top retaining screw at back of oven

Followed by another three T15 Torx screws and washers underneath the stainless steel fascia.

Front cooker top retaining screws

On top of the hob each of the gas burners was held on with two T10 machine screws

Hob burner retaining screws

and each of the controls had a knob that could be pulled off with a bezel attached by a further two T15 Torx screws. The grill/top oven control had a small spring between the knob and the gas control.

Location of bezel mounting screws underneath control knobs

Twenty-three screws later and the top was loose. What I should have done next was lever off the stainless fascia and remove its earth tag giving access to the command panel,

Fascia retaining clip and earth tag locator above first control knob recess

this might have allowed me to remove the command panel without disconnecting the whole cooker top, But instead I removed all the spade connectors from the command panel at the front (4) and the hinge housing (16) at the rear of the hob, making sure that before I disconnected them that I had a note of what went where.

Command panel connections viewed from rear of machine

Hinge housing connections view from front of machine

Connection diagram Zanussi ZGC551GXC

This allowed the cooker top and attached lid to be lifted forward and off the oven and the command panel to be removed from the two silver retaining clips.

Command panel released from cooker top housing

The command panel could then be released from its translucent brown plastic enclosure and the remnants of the broken button were released.

Disassembled command panel

To repair the button I drilled out a 1.5mm hole along the shaft of both broken ends of the button, inserted a suitably sized piece of stiff 1.5mm wire and glued it back together with superglue.

REME

All that remained was to repeat the disassembly process in reverse

Reassembly of oven

Including the door gasket fix I reckon to have saved £30 in parts and £120 in labour for an engineer. JOB DONE.

Time spent : 1 day including cleaning/drying time
Cost : £0.00

Oven Repair Ib

Fixed, but not for long; the door gasket was found hanging down into the main oven about two weeks after it was put back into position. On the plus side it wasn't the repair that had failed, on the minus side it was broken again. Back to the bench for more aluminium foil and staples and straight back on. Let's see how long it works for this time.

Time spent : Another 30 mins
Cost : £0.00

Oven Repair I

Moving along, the next item suffering is the oven. There are two faults, a broken button on the control panel and a failed seal on the top oven/grill. The oven is a Zanussi ZGC551GXC gas oven.

I started with the seal, just because this should be the easiest one to sort, in access terms at the very least.

Broken top oven door gasket

Removing the damaged seal was not a problem, it was held on with 4 hooks at each corner. So the whole thing just pulled out easily. The next part of the job was to get a bucket of hot soapy water and start cleaning both the stuff as it came off the oven and the exposed areas left behind.

Rear view of removed gasket 

You can see from the picture that the top portion of the seal has had more heat damage than the bottom which why it has parted there.

A quick trip to the Zanussi support pages yielded no information. Not even a link to their on-line parts shop where all the part diagrams, part numbers and prices are! So a replacement seal would have been £21 plus £2 p&p and another £8 for a replacement timer button, or £31 for the pair. The seal is only mildly expensive compared to button which costs its weight in 9 carat gold. Time to make do and mend I think...

Cross-section of door gasket

On inspection I found that gasket was originally sealed by inserting a joining piece into a void running the length of the gasket. It seemed that I could just replicate this. As I wasn't sure how hot the gasket would get in operation I plumped for a piece of thick aluminium foil folder over.

Foil from top of coffee can

Folded across a wire to make require profile

Using this and a piece of wire to form the spike in the profile I made a 4 inch piece to join the ends.

Home-made joining segment

As you can see from the photo, this was only partially successful as the perished rubber had a tendency to part. When I refitted the gasket to the door the aluminium kept slipping out of the rubber so to prevent this and deal with the perishing I reinforced it with four staples underneath the flap of the gasket.



Repair reinforced with staples

This worked and the whole thing went back into place with no problems.

Repaired and refitted top oven gasket

The less damaged part of the seal is now at the top of the oven aperture and hopefully we'll get a further 4 years of service out of it before it needs properly replaced. On to the snapped button!

Time spent : Day split over an afternoon and morning
Cost : £0.00

Dishwasher cleaning products

Yes, I have got the bit between my teeth regarding maintenance of the dishwasher. As I noted the water matrix looked a bit gunky but impossible to clean manually. What to do? Use a dishwasher cleaner I guess.

Based on a Google search for dishwasher cleaning products, the three most commonly mentioned are Finish, Bosch and Dr Beckmann. But what's in them, what do they do, and are they really required anyway?

Let's start with Finish which has been available in two formats.

New Finish

Old Finish

The older one appears to mostly be citric acid (15-30%) and a non-foaming detergent (5-10%). Why non-foaming? Because this is what happens if it isn't. While the newer one is exactly the same thing but with a splash of EDTA and bit of glycol ether (presumably to help form the upper blue phase and assist the detergent's effect). So in both cases it appears to be a bit of acid/chelator to descale and break down any fatty deposits and a non-foaming detergent to help shift any stubborn stuff.

As it's a powder, Dr Beckmann's has a different set of active ingredients being mostly sodium percarbonate (20-25%) and some coyly named oxygen-based bleaching agents (15-30%) which are probably also peroxide derivatives or activators for the percarbonate (I wouldn't be surprised to see EDTA in the mix again as well).

Dr Beckmann

Finally the Bosch dishwasher maintenance powder has a more comprehensive set of ingredients but the main constituents are citrate and percarbonate. There is also sodium silicate (an astringent), sodium carbonate (washing soda), longer chain detergents, EDTA, and a couple of industrial enzymes, amylase (a starch buster) and subtilisin (a protein buster).

Bosch maintenance powder

In summary the cleaners appear to be either citrate and/or percarbonate based plus/minus a non-foaming detergent. They are targeted at descaling, dissolving fatty deposits, and shifting stubborn residues that your regular dishwasher detergent isn't moving.

On the question of "Are they worth it?" there seems to be a lot of debate. The commercial cleaners generally recommend a monthly application. So, at anywhere between £2 to £6 per dose (or £25 to £75 a year) and given that a reasonable dishwasher will cost about £300 and should last ten years, if you are not using one of the commercial products and if (and it's a big if at that) this halves the lifespan of your machine you would have paid almost as much on even the cheapest cleaner as it would cost to replace your dishwasher every five years rather than ten. In that light they appear to not be very cost effective. More so as the bulk cost of the component chemicals is only a few pence.

The following comment from the Money Saving Expert forums gives an expert perspective,

"So do use the salt chamber and keep it full, buy rinse aid and add it and you will get nice clean stuff out every time, don't waste money on Calgon, dishwasher cleaner or tablets with added rinse aid or salt either because it's just a marketing con, I used to build and repair £20,000 commercial dishwashers so I know a thing or two about them."

Reading the thread a range of cheaper substitute options are suggested, vinegar, bleach, baking soda, washing soda, and bicarb. Of these vinegar seems the most commonly recommended, both as a cleaner and as a rinse aid (see here and here).

However there is some controversy about whether using vinegar (aka 5% acetic acid) will damage the seals and internal tubing of your dishwasher. A bit more digging shows that more seals are compatible with citric acid than with acetic acid, which may be one of the reasons why some of the cleaners are citric acid based. Whether this matters if vinegar is only being run in the machine a few times a year as a cleaner rather than routinely as a rinse aid I can't be sure.

Certainly some manufacturers specify that vinegar is safe to use in their machines, but the manual for ours didn't. The best way to establish if it is safe or not would be to contact the manufacturer, but with Neff that's another story...

In the meantime, the Finish bottles contain about 30-60g of citric acid which is easy to get hold of in food grade form. Five pounds will get you enough for twenty 50 g (=2 tbsp.) doses that can do the job of £80 worth of Finish cleaner. The loose crystals just be bunged into the powder compartment and run through a hot program. Percarbonate is also readily available but replacing the non-foaming detergent is a more awkward, but not impossible, proposition.

But if I'm just trying to replace a vinegar clean then a citric acid only swap seems most straightforward. I think I feel a trial coming on.

Dishwasher MRO

Ok, so now the dishwasher is back in action how do I keep it that way? Well the manual for the machine had some advice

􀊋 Check spray arm for grease and limescale deposits.
If you find such deposits:
􀊋 Fill detergent dispenser with detergent. Start the appliance without utensils in the programme with the highest rinsing temperature.
Clean the appliance with detergents/appliance cleaners which are particularly suitable for use with dishwashers.
􀊋 To extend the life of your appliance, clean the appliance regularly with a special dishwasher detergent.
􀊋 To ensure that the door seal always remains clean and hygienic, regularly clean it with a damp cloth and a little washing-up liquid.
Regularly wipe the front of the appliance and fascia with a damp cloth; water and a little washing up liquid are adequate. Do not use sponges with a rough surface or abrasive detergents, as these could scratch the surfaces.
Special salt and rinse aid
􀊋 Check the refill indicators and, if required, refill salt and/or rinse aid.

.... blah, blah, blah, yawn.

More succinct instructions were to be found on the Which website, where a nice man in a suit shows us how to clean an immaculate dishwasher. I kid you not, look

Britain's Best-dressed Dishwasher Repairman

The list of to-dos is straightforward and the provision of repeat periods means the information is easy to put into a recurrent job.

1. Clean the dishwasher filter - Weekly
2. Wipe the dishwasher door seals clean - Weekly
3. Top up with dishwasher salt and rinse aid - Monthly/when indicated
4. Remove and clean the dishwasher spray arms - Six-monthly
5. Run the dishwasher empty and hot - Six-monthly

JOB DONE.

Break-time over

Ah well, back to it.

Currently we're having a white/brown goods situation, so let's start with the dishwasher, which presented itself like this,

mmm, lovely.

After emptying the machine by hand and checking that the pump wasn't blocked and was running freely, running a rinse cycle replicated the problem so it wasn't a flyer. Taking the machine out of its' alcove showed that the waste path out of the washing chamber didn't seem too bad.

Water handling matrix of a Neff S51E50 dishwasher

The waste flow is the corrugated pipe coming in from the pump on the right-hand side and going up into the matrix, the flow then loops over and exits out via the white pipe to the back of the machine. Visually it looked OK. There does appear to be some residue in part of the matrix but A) I'm not sure this is causing the problem and B) there is no way in to clear it out as the matrix appears to be a sealed unit. Running a rinse cycle into a bucket worked fine.

The next port of call was the path from the waste pipe into the sink waste water plumbing. No need to see that part of the process, it was pretty foul (it'd gie yer the boke).

40mm waste water pipework

40mm trap seal (L - old/R - new)

After cleaning out many years of grot and replacing a dodgy 40mm trap seal that had been stretched and was leaking slightly it went back together no problem.

So all good, replaced the dishwasher waste pipe and ran another rinse cycle and hey presto! No change.

Disconnected and repeated the rinse cycle running it into a bucket: no problem. Is the pump not efficient enough? Ran another rinse cycle with the waste pipe elevated above the height it would usually connect at; no problem. Hmm..., reconnected it back to the waste piping and now it's back to working normally.

What was the problem? Basically I'm not sure. Current and final thoughts are

• Waste water was not draining, but pump was working. Therefore, probably, not due to a blockage in the waste path.
• So either the programmer or an associated detector wasn't working properly.
• No reason why it should just start working again if it was the programmer.
• A flaky sensor is a possibility but that is likely to reappear as a fault.
• Or the check valve on the waste outflow (if there is one) was allowing waste to siphon back into the machine.
• But on the first occasion the water was very gunky, indicating that it hadn't been through the rinse cycle at the end of the programme, so siphoning seems unlikely.
• Or the pump wasn't working properly.
• But if this was it, it must have been a blockage rather than a mechanical issue with the pump.
• Or repeated rinses may have removed an obstruction or crud and this might have brought it back to life.

Or in short, I have no idea but don't care as long as it keeps working.

Time spent : Day and a half, off and on.
Cost : £0.59 for replacement washer.