Ideal icos boiler, no hot water, flashing burner light

[JackA2288]

Hi,

New to the forum, with limited plumbing / CH knowledge, so any assistance would be greatly appreciated.

My set up - Ideal icos boiler, Siemens RWB29 programmer, Siemens thermostat, Megaflo CL170HE water tank. Already installed in my home (roughly 8 years old) which I purchased a year ago.

On Thursday of last week I came down to find a puddle in the lounge, it became apparent the Megaflo tank was leaking on the first floor, appeared to be coming from the overflow valve. I followed the recommended instructions on the Megaflo tank and this stopped the overflow valve dripping. Went on holiday hours after this was resolved and came back last night.

Luckily no more leaks from the Megaflo tank but now unfortunately no hot water.

When I override the hot water to come on via the programmer the boiler status shows C and the burner light flashes continuously and no hot water is produced. I noticed the pressure was down to 0.5 so topped this back up to 1.5 but it had no effect.

Central Heating works fine - radiators are blazing hot but after having both CH and HW on for over an hour there is still no hot water from the taps.

Not sure what to do from here - not sure if it means anything but there is a couple of seconds of warmer water when running the hot tap but then it goes back to cold. I've tried the classic turn it all off and on again with no luck.

As I said, a complete novice so any assistance would be great thank you!

 

[Riley]

Hi and welcome to the forum First things first I think you need to get your megaflow looked at as it shouldn't have been overflowing in the first place. Get a G3 qualified engineer in and then go from there. other than that that re pressurising it and sorting the air bubble you aren't legally allowed to touch anything on it

 

[stevetheplumber]

the c means there is a call for the boiler to fire so its not an external fault but not sure about the flashing burner neon( i thought it flashed when satisfied ) and strange it works for heating which makes me think external controls ,might be worth checking the overheat stat on the cylinder

 

[JackA2288]

Thank you both for your responses.

I certainly plan on having a professional looking at the system but I was just hoping there might be something I could do in the interim to provide some hot water - not ideal to have none with children in the house.

I've got both HW and CH on at the moment and the boiler burner light is constantly lit, unfortunately still no HW.

Where would I find the overheat stat on the cylinder?

ive just been looking at the cylinder and found a dial which was set to '0'. It's coming off the mains water supply to the cylinder. Has the option to go up to 7 - is this set right?

Thanks, Jack.

 

[gassafe]

Not a boiler fault if it works for radiators...

Check cylinder overheat has not popped (probably found behind panel on megaflo) or 2 port valve failing to open...

 

[Riley]

Unless Im mistaken you have an unvented cylinder The temperature and pressure devices on these are set at certain levels for your safety. Can I please recommend that you don't adjust anything and get an engineer out to look at it. Not to sound all drama queen but these things literally can turn into a bomb if the safety devices are messed around with.

 

[gassafe]

Thank you both for your responses.

I certainly plan on having a professional looking at the system but I was just hoping there might be something I could do in the interim to provide some hot water - not ideal to have none with children in the house.

I've got both HW and CH on at the moment and the boiler burner light is constantly lit, unfortunately still no HW.

Where would I find the overheat stat on the cylinder?

ive just been looking at the cylinder and found a dial which was set to '0'. It's coming off the mains water supply to the cylinder. Has the option to go up to 7 - is this set right?

Thanks, Jack.

Would need a pic to know what your referring too.

 

[JackA2288]

Thanks, not adjusting anything

Struggling to upload an image via my iPhone. Having a second look I don't believe it's the mains supply as the pipe is hot.

 

[village idiot]

Thanks, not adjusting anything

Struggling to upload an image via my iPhone. Having a second look I don't believe it's the mains supply as the pipe is hot.

If the hot pipe is near somrthing like this V4043 Motorised Zone Valve - Honeywell UK Heating Controls , then the valve is the problem

 

[JackA2288]

This is the valve / dial I mentioned, currently set to 0

 

[gassafe]

Leave that valve alone... Probably one of those 2 ports at fault... Should be able to manually open one to see if the pipe gets hot