Diesel garage heater

There are a bunch of these heaters sold under lots and lots of names.

This one in for repair is a Kende spark 30, 28kW, on wheels

There was a small fire that ruined the wiring and destroyed the photocell (LDR) Parts are readily available in the USA, but not in Europe at anything approaching a fair price. The PCB got toasted when the wiring shorted to chassis. The PCB is live chassis. There is just an on switch.

Very simple operation. The fan and ignitor run all the time via a triac. If no flickering is detected by the LDR (either the flame or ignitor) it shuts down in 2 seconds. To reset unplug for 10s.

The LDR choice doesn't seem critical so long as its change off resistance is enough keep the schmitt NAND from triggering. See the circuit for some figures. I had to replace the Q3 transistors (generic BC547) and the IC CD4093

Grain mill

 Not a part 2 of the home made grain mill, but a how-to-use-a-bought-one

The wooden one I blogged about just wasn't able to crush the grain.

A cardboard chute to funnel the grain. A large socket on the wing nut instead of the handle.

About 30 mins for 8kg.

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.