I do love it so much when you tell me off for doing something I didn't know I shouldn't! This is the first secondhand phone i have ever bought and it worked fine until 4g started flipping around.

It is with 3 which is how I know I have no coverage, because, of course, I went on the internet to check what coverage I have. Or rather I do but cannot talk as I don't have a phone that is 4gVoLTE or "calling" compatible. Still works for texts, internet etc.
So none of the above "Yer" statements are the reason. The closest would be "Yer fone is old old cr@p that doesn't have 4gVoLTE." They've switched it off for peeps like me so that I go out and by yet more of their carp. so they will simply lose a customer.
My really old Motorola V171 on Tesco Mobile pay as you go, still works fine, I can still talk on it and send texts and apparently even use it with the internet if I could be bothered to find out how. It cost peanuts new. And it works on the strongest signal it can find.
Nothing wrong with the antenna, on either of my mobiles. It works as well as any of our phones here and in Frogland.
View attachment 330005
Go into:
Setting \ Connections \ Mobile netwurks

Hhen click on Netwurk connection

Make sure its set to 4g 3g 2g auto connect

Eye is with 3 anorl. Via Smarty. Unlimited calls and text, wiv 6gb of internet. All fer 6 sovs per month. Other packages available.
 
Right.
The HW issue is sorted. One closed gate valve which is now open.
I have precisely one motorised valve that's all.
But, like you I am mystified as working on all the central heating systems, gas boiler driven, that I have had in 4 houses, I have never had a problem like this.
I have had one airlocked rad once up until now.
I thought I was getting on top of it before dinner, but while we were eating it went back to square one.
I nearly had nearly all the rads working.
I think I tried to go too fast, getting one rad working, then another, then another..... I had all 3 on the top floor working, then carried on downstairs, got one working, then tried to get another on stream..... That's where it went wrong.
I'll be back on it tomorrow, taking more time and after having done more research. It is only a 7 rad system now as the other 7 have all been closed off for ages.
I just wish I could visualize it and see how the airlock or airlocks developed in the first place, then I might be able to solve it.
I think my system is the same as yours. Called a "Y" plan with one motorised diverter valve. All HW, all CH or Mixed flow.
On mine there's a link in the 10-way control box to give "boiler priority" so if the boiler is under temp it "calls" and the valve gets operated to no rads and all HW. I wonder if you have a dicky tank thermostat permanently calling?
Best of luck with it. Grovelling around on the floor at our age is no fun at all is it? :(
 
Morning All. :D
Off for my yearly Abdo-Aortic-Aneurysm MOT this morning. Wish me luck!
Got some specialist steel tube in y'day and I have begun making another 2WD unit for pedal car racers.
OK gotta go, appointment is at 09:10, see ya'll.
Have a fabulous Friday. :D
 
Who’s Fred? 🤷‍♂️
Here's a couple ----

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