Plumbing

Moved the Caleffi 533251 3/4 pressure reducing valve (PRV) with manometer from the HW system to the incomer.

Turns out it was quite blocked. Fitted ~2012

Ordered another complete valve 533651 as  it was the same price as just the cartridge, and gave me more options if my body was damaged. Received a 2018 vintage. Thanks.

Use molegrips on the bolt head to remove it. Tricky enough in the vice. Will need to jiggle it a lot and lever it with a screwdriver. Can be removed in situ ok. Not a lot of water inside.

Tidy enough. Wiped the body out and put in the new one. A smear of silicon. A bit of chrome missing. New one isnt chromed. 

Cleaned the old one with carrefour descaler. 5 mins for the screen, and 2 x 5 mins for the body, turning it. Has dulled the brass.  In future try half strength for 5 mins.

6/8/25 noticed the pressure creeping up to around 4 bar over time and the shower dripping. Removed the cartridge and put back the original. The main seat had some scale which was removed. More chrome missing. Not convinced that it's regulating correctly. Isolated the hot water feed but that didn't change anything suggesting that it's not a mixer tap passing.

Hedge

 Cut the hedge nearest the hoogle bed and the south one. 5 hours. Had gone wild with the damp warm weather. About 3m2

Then thinned the goat willow on the north boundary which was giving too much shade to the fruit trees.

Dyson Max brushes not rotating

 If the brushes on you Dyson hoover stop working, you've probably worn out a pair of contacts. Initially test the brush head. I used 16V as it was to hand. It takes ~1A. Polarity nmot important.

Follow this video https://youtu.be/UafhshE0Th8?t=120 and remove the clear dust collector (use the open button to first open the door, then press some more and wiggle and the container comes away, rotated around the front nozzle.

You can see the 2 contacts on the right. Clean and blob some solder.

If you pull the cover on the other side, you can test for a connection - about 5R, on the red and white twisted wires. There are also 2 hidden filters, so clean those under the tap, dry, replace.

Asustor NAS UPS

It's stormy here in the Pyrenees this year and we are experiencing a lot of brownouts. The brownouts are long enough that the NAS reboots and then grumbles for a while whilst it verifies all the files.

A small UPS was needed, but not something that is going to cost the planet. I have several UPS, mostly APC and they are shockingly wasteful. So much so, that I use the best one on the PC and turn it off when the PC is off. The rest of the time I don't care about the energy it wastes as the solar panels 'pay'

The NAS uses a 5.417A/12V external psu and a barrel plug. I contacted Asustor a few years back to ask what the tolerance was for the 12V input. They refused to answer the question. Reading between the lines, they didn't know. I guessed that the 12V was used to just power the hard drives. Picking a few SATA disks at random, the spec was the standard +/- 10%, meaning 10.8V to 13.2V. This almost fits quite nicely into a standard lead acid battery. Li-on is no good as 10.8V is pretty much fully charged.

The AS6202 takes ~1.5A at 11V, 25% cpu & ram, 2 SATA disks. Using a fully charged, 20 year old Yuasa 7Ah/12V (measured capacity 3.5Ah) I got the following. The battery was connected to a Y connector with the normal psu. A 1n5400 diode and a 2.6A fuse.

SLA 12.38V off load. 

PSU off. SLA 12.03V. Volt drop across ammeter 0.17V, across diode 0.811V. 10.98V to NAS. Bleed through diode when psu on <0.2uA

I'm not going to get a lot of battery back up, but brownouts are avoided. I'll charge the battery monthly (disconnected)

In due course (!) I'll put LVD protection for the battery.

Some of the items in the house are supported by a Victron Multiplus II which is semaless in keeping the power on, but not the NAS. The NAS is wired to the router, and the router is a lightning conduit. I don't want lightning to get to mul

Drive Cam

 A very simple case for a semi-stealth ESP32-CAM camera that is screwed to the underside of the soffits.

Mains detection

A long story, but I needed to detect the position of the switch in the kitchen that enables the kettle to run off PV surplus. I'd always managed to detect it in software, but I now need the physical position

 Very simple. A 817 opto coupler. A 4n7-10n X/Y cap and 100R in series with the mains. A 1N4148 inverse parallel with the diode. A 22u tant across the output. Pull it high with a 10k to +5 and you have a detector that consumes about 100uW. Sure there's a bit of 50Hz ripple at 0.35V but it's well below CMOS threshold.
..1 month later

Seems I hadn't tested this across a big enough input voltage. At 240V, the opto output was falling between the ESP32 thresholds. A 18k across the 22u tant gives 0.9/2.1V. Just ok. Design needs a re-visit.

Hoover

 Last week the cordless Hoover made so much noise even ear defenders where not enough.

It was vibrating so much the dust box was coming off on its own.

Opening up didnt reveal anything, and the vortex/motor assembly was quiet once removed.

It was bought 8/6/2020. 2.5 years later and the fan blade was thick dust.

Motor part number.

Never did get to the bottom of the noise.