Recent content by DavidLewis

I believe you can also downsize the vent pipe to 82mm diameter from 110mm diameter, to save more space if you want...

OK, it's working again! It turns out the fault was the water pressure sensor. It is a 5V-powered electronic sensor which had failed short-circuit, overloading the 5V power supply part of the PCB. The 400mA soldered-in fuse protecting the circuit had blown, which caused all other parts (such...

Could be. Although the pump on these is not modulating, and is probably (I haven't investigated) switched directly by one of the mains relays on the board. So it's difficult to see how a shorted pump would cause the damage I'm seeing to the PCB. But thanks for the idea - I'll investigate...

Ha! Put like that, it is tempting! The thing is, we were half thinking about moving the boiler location to the garage as part of a kitchen knock-through project. But not until next year... Would be good to get another six months out of the old Viessman for this reason.

No water leaks. I've tried reconnecting each cable one at a time after replacing the fuse, but I think the damage to the PCBs has already been done. I'm not going to sacrifice a third PCB in this way... It was a pretty nice condensing system boiler. Dual temperature, hot water priority...

Hi all, I came down in the morning to my Viessmann's fan running flat out, but no heating, and a completely blank display (so no error code!) and no lights illuminated. With these symptoms, I assumed it was the PCB so bought a brand-new-sealed-old-stock one and fitted it this morning. My...

Thanks - I'll buy some for next time. I've run out of PTFE tape now anyway :LOL:

I suppose you are correct. I did, in fact, make up another draincock using a tapered-thread coupler and a plain draincock. But the amount of taper on the thread was surprisingly small... 30 turns of PTFE tape later (20 wasn't enough!) and the thing is installed nicely. So I guess...

Ok, I admit I'm just assuming the female thread on the cylinder is parallel. I am therefore wanting a male tapered thread on the draincock. The draincock I have is parallel-thread, and doesn't get any tighter as I screw it in, until its "shoulder" touches the boss on the tank. But, as far as...

Hi all, My nice new Gledhill copper cylinder has a tapping for a drain cock. This tapping is 1/2" BSP female parallel threaded. I naively thought the drain cock I bought https://www.toolstation.com/made4trade-mt-cock-type-a/p83905 would come with a tapered thread, but no, it's parallel too...

a bit like the old trick of using squashed bread to temporarily block a pipe? ;)

I agree. I have a couple of Mira Platinums off a large shower pump. They are great (particularly compared to the Grohe Digital ones they replaced!) but if I was installing them from scratch I would go for the ones with inbuit pumps. I'd stick with Mira because I've been happy with them.

I live in a village, apparently surrounded by decaying water mains. We have "water cuts" several times a year while roads are dug up and mains are repaired. I know this because those of our neighbours who have converted to combi boilers or unvented cylinders post on the neighbourhood Facebook...

It's a system boiler, so internal pump. It's set at the lowest pump speed, so that return temperatures are low for maximum condensing operation.

I have no idea what causes it. Mine's a sealed system, with JG pex barrier pipe. The fact that the "flakes" (actually, they're more like crushed seashells) are black and magnetic means they must be iron, which must come from the radiators. But why they happen at all, and particularly why they...