Megaflo suddenly stopped heating

[izzyk]

I've had a megaflo for many years without problems. Serviced (fairly) regularly.
It has suddenly stopped producing hot water. The pressure is good but the water is cold. I've noticed the outlet pipe feels warm and you get a couple of seconds of warm water then it goes cold. Leave it for a while and it heats up a tiny bit again, but it doesn't seem to call on the boiler at all. Could this point to a fault in the wiring?

I've regenerated the air bubble as suggested.

We've had building and plumbing work going on in the rest of the house so that could be the cause.

Waiting for my plumber to get back to me, but I just wanted to see if it could be anything simple.

Thanks.

 

[justlead1]

Hi. If its heated other than an immersion heater (which also has a cut out high limit stat) The flow pipe feeding the heat exchanger coil within the vessel will be fitted with a 2 port motorized valve. This is wired via a high limit stat to protect the water from reaching high temp and entering a dangerous condition. Other than flow and return circulation problems, this valve is an area i would investigate and why it may have shut. Good Luck

 

[izzyk]

Thanks. I've decided to play safe and call out the heatre sadia engineer. I'll post back what the problem turned out to be. Thanks again.

 

[izzyk]

It turned out to be that the diverter motor had gone. Now that it's been replaced the system works fine. I think that's what justlead1 referred to.
I had forgotten that there was an immersion element as a backup, so I could have had hot water while the system was broken. I'll try to remember next time (if there ever is one).
Thanks for the response.