Do the ultrasonic level meters ever go wrong?

CliveOfIndia

lohr500 said:

The red was added to make it obvious to revenue inspectors who carry out roadside checks.

Must admit, the "roadside check" thing has always puzzled me.  The same as farmers using their red diesel in cars when they're not supposed to.  I know heating oil has some sort of marker in it (whether visible or not, I don't know), so that it can be detected.

There's no mains gas in our village, pretty much everyone uses oil, a few use LPG.  But I would have thought it would be a prime location for HMRC or the police or whoever to do random checks to see if people are running their cars on heating oil.  But in all the years I've lived here, I've never seen anyone being pulled over.  I mean, obviously they must do it, as that one guy got done ages ago, it's just I've never seen them out and about.

Maybe it's not such an issue now, as newer diesels wouldn't tolerate it anyway?  Although, there's still plenty of really old cars knocking around here.

I'm just wondering how common these roadside checks for "illegal" fuel actually are.

lohr500

Not sure how frequent the roadside checks are.

Years ago they would be a regular feature around the livestock auctions in our area. Lots of rural myths about farmers having Land Rovers with split tanks. White diesel in a small section of the tank connected to the filler pipe. Red diesel in a much bigger section of the tank. I would imagine the fine/consequences for such a stunt would be much bigger though than just running on red diesel alone. 

I bet they dip HGV and van tanks when they pull them up for spot weight and condition checks. 

quartzz

I've shone a torch into the viewing hole in the dark to get a clear view, and I reckon there might be about 2 inches in the bottom of the tank (the tank viewing hole which I thought was separate from the main tank). So it was a good idea I've ordered some more, hmm. I also got a clearer view of the actual insides of the tank, and there don't seem to be separate compartments which is what it looked like before, it's "a tank"

I've just done some vague calculations. I reckon the tank might have been 1/3 full when I got here, that's 200L. say 100 days used 200L, which gives 2L per day (£1.20 per day?). the Ultrasonic is set at 110cm, or 43 inches. 

43/3 is 14 inches. so 14 inches lasted 100 days, or 0.14 inches per day. where's that tanker.. (if anyone wants to redo my maths, pls be my guest?)

lohr500

A couple of suggestions : 

Get a stick and mark the oil level just before the delivery, then again immediately afterwards. Then you will know how much higher the level is with a known delivery volume.

If there is only a small amount of oil left in the tank, then its even more important to let the oil settle after the delivery before running the boiler. The new oil will splash around as it is pumped into the tank and will disturb any sediment and water in the bottom of the tank. If you run the boiler straight away, it risks drawing that sediment into the feed line which will clog the filters and possibly block the blower nozzle if the existing filters are damaged.
I would leave it for at least 24 hours if you can cope without the boiler for that long.
If finances allow it, I would be getting the next delivery well before you hit the 2" level so the sediment disturbance is reduced. The outlet hole for the tank is not at the very bottom, so you must be very close to running out. It also gives you  bit more of a buffer if there are any delays in delivery. 

QrizB

quartzz said:

I've just done some vague calculations. I reckon the tank might have been 1/3 full when I got here, that's 200L. say 100 days used 200L, which gives 2L per day (£1.20 per day?).

A litre of oil contains about 10kWh of heat. 2 litres / 20kWh a day sounds a little low for winter, unless you have a super-insulated home?

quartzz

thanks for the info's. Inside the tank with a torch shone at it I can see the moldings for where the pipe exits the tank, but as far as I can see no actual exit holes. So possibly I'm about an inch above where the liquid is actually drawn out (?). My oil usage isn't high, to be honest (?). I'm usually only running 3 out of 6 radiators (2 TRV downstairs, and the towel radiator in the bathroom), plus some short hot water bursts and the shower

Doing net searches have given me all sorts of new terms to use. I think this property is quite well insulated, but has low thermal mass, so it heats up fairly quickly, but cools down fairly quickly. when it was frosty outside, the roof tiles still had frost on them into the afternoon, so I am guessing not too much was getting out through the roof

I'll certainly try for that pause to let gunk settle. instinct is "got oil, heeeeat", but the method of easing in slowly after "power restored" I've seen applied to other things too (there was a computer networking department in the 90's, when the power went down the employees got annoyed that the network wasn't available instantly after the power was restored. the network admin guy explained that if he put it online the moment the power was back on, 200 employees all trying to access a 90's hard drive would break it)

to answer the question, yes, ultrasonic level meters can go wrong

new battery has arrived. I can confirm, that 2.94v is not enough to run a watchman ultrasonic transmitter. and apparently, 2.94v is not enough for the transmitter to tell the receiver, that the battery is dead. Possibly I should have tried the trick of tapping on the LCD display, to see if that would dislodge the bars on the display..

I'm still not sure what this mirror I appear to be seeing is. it seems too clear cut to be just the reflection from a layer of liquid at the bottom of the tank, but.....actually a mirror?

quartzz

I've replaced the battery, paired it (the pairing was doing nothing with the old battery, now it "sonar blips" within a second of doing the pairing procedure), put the U/S sensor back onto the tank, and all of a sudden, I have a flashing red LED and no oil. so, that's.....great. my top tip for today - realise when breaking the warranty void if broken seal, is what you need to do

lohr500

A good result then!

I would still get a broom handle, or a length of dowel so you can do a before and after dip check on the oil delivery. 
The digital gauge is handy to give a rough estimation of the oil in the tank (when it works ) but it isn't very precise.