Anti cycling

Another reason I think the valve is passing hot water through it (even though not being asked to be open) is because I always seem to have hot water and the taps/showers no matter how much I draw off.

With my old set up, I'd regularly run out of hot water by evening.

Is there a way to test the valve?

Is this s plan. Anyway iirc you have a megaflo so the supplied 2port should be blocking flow to the heating coil when no call from the stat. You sure you havent got a wiring issue maybe valve is opening when CH is calling. Just turn off HW generation and let CH call and feel the coil pipes on the megaflo. Also check the obvious that any immersion is not switched on or being fed by something.

Yes, it's all on S plan.
Would the megaflo have come with it's own valve?
When my megaflo was installed, they simply reused the existing honeywell valve that was already there.
Same with the heating valve, the existing one was reused.

I don't think the DHW valve is faulty (it seems to travel back and forth the same as the heating valve right next to it, and it also 'feels' the same when you operate the lever manually.)

I've checked the wiring, all appears fine. It's only three wires, and I've tested that voltage is applied across the valve terminals depending on heating or DHW demand.

There isn't even an immersion wired up to my megaflo, so that can't be it either.

I'm going to run the heating without any hot water at all for a day or two. So once I've used up the hot water in the cylinder, there should be no hot water available at all.
If after a day's worth of showering and washing etc, there's still hot water from the cylinder, then that will confirm that somehow the heating circuit is also heating the cylinder.

mrshr said:

Would the megaflo have come with it's own valve?

Click to expand...

Yes