Low water alarm comes on when tank is full

Ben Hill

I apologize if this has been covered elsewhere, I did a brief cursory look and didn't see anything.

Multiple times yesterday we would hear the low water alarm come on, only to check the tank and see that it was still half full. It almost seemed as if it knew the boiler tank was low, but did not kick on the pump.

Each time, some amount of fiddling got it working again (turning it off and then on, or pulling water through the group would sometimes get it to pump again and the alarm goes off).

We use an in tank filter. I'm not sure if there's any way that can get clogged in such a way that stops the water flow, but you'd think the pump would still kick on if that was the case.

I'm mostly concerned because I don't want to damage the boiler/element. Any ideas what could be causing this to happen?

Thanks!
Ben

Frans Goddijn

What happened when you removed the in tank filter?

Reiss Gunson

hi there ben

a search using the phrase 'low water alarm' reveals quite a bit of prior history on this issue;

https://londiniumespresso.com/component/search/?searchword=low water alarm&searchphrase=all&Itemid=130

my first question would be; are you removing the water box from the machine to refill it?

kind regards

reiss.

Ben Hill

Thanks Reiss, not sure why, but when I did that search I only saw 5 results. Thanks for posting the full results.

Based on other threads, I think the most likely thing is an air bubble in the pump, because flushing water through the group seems to clear it. The only thing is, several hours later with the reservoir more 50% full, the alarm will sound again. I'm not sure if there is air trapped in the pump that just presents itself now and then.

Frans Goddijn

How recently was the in tank filter replaced and what is the difference without it?

Ben Hill

We replaced the filter about a week ago. I haven't tried running it sans filter. I only removed the filter and then put it back in, which may have helped. Next time it happens I'll try removing the filter and leaving it out to see if that makes a difference.

Frans Goddijn

There was one earlier question:

are you removing the water box from the machine to refill it?

Will be good to hear if you do, or don't.

Ben Hill post=12462 wrote: We replaced the filter about a week ago.

Did the issue also happen before you put in the new filter?

Was the filter fully immersed in the full tank all the time?

Ben Hill post=12462 wrote: Next time it happens I'll try removing the filter and leaving it out to see if that makes a difference.

Or removing the filter but leaving it in another container fully immersed, so you won't replace water with air in the filter.

Reiss Gunson

hi ben

i do need a reply to my question if I'm going to make a meaningful contribution to resolving the issue;

are you removing the water box from the machine to refill it?

and my next question would be; what change did you make to the 'system' immediately prior to this issue arising?

i.e. are you saying you never had this issue until you changed the water filter cartridge?

kind regards

reiss.

Ben Hill

No, we are not removing the water box from the machine to refill it. Is this something we should be doing?

We changed the filter and cleaned the shower screen a few days prior to this issue arising. The issue had not happened at any point before changing the filter.

We won't be open again until Thursday, so the machine will only experience light use until then. I'll post if we experience the issue again.

Thanks for the help!

Reiss Gunson

hi ben

ok, so that's good news; i dont recommend removing the water box for refilling

from what you write it sounds as though it is linked to changing the water filter cartridge

i think you should remove the cartridge and place it in a sink full of water, or a saucepan if you prefer

lie the cartridge on its side, or better still invert it so any air trapped inside can more easily be displaced by the surrounding pressure of the water that the filter is immersed in

leave it immersed for half an hour then refit the cartridge into the water box

when refitting push & twist the cartridge into the adaptor sleeve

i think that will solve it (i think you have air trapped inside the cartridge which the pump is drawing out)

if you feel that the pump now has air trapped in it simply disconnect the pressure hose on the outlet side of the pump and let the pump run for perhaps 5 seconds to displace any air that may be present, then reconnect the pressure hose to the pump

let me know how you get on

reiss.

Ben Hill

Thanks Reiss, will give this a shot!