# Air in boiler



## Jimble101 (12 mo ago)

I have a mara-x that has been running great since purchase. Yesterday the water reservoir ran dry while the machine was switched on and some air appears to have got into the boiler. when I turn on the machine and brew a coffee, the brew pressure is lower than normal (c. 4bar rather than 9/10 bar).

grateful for any advice to restore the brew pressure


----------



## MediumRoastSteam (Jul 7, 2015)

Jimble101 said:


> I have a mara-x that has been running great since purchase. Yesterday the water reservoir ran dry while the machine was switched on and some air appears to have got into the boiler. when I turn on the machine and brew a coffee, the brew pressure is lower than normal (c. 4bar rather than 9/10 bar).
> 
> grateful for any advice to restore the brew pressure


 The MaraX should've prevented this. It has a water level sensor where the pump should have stopped before the water tank runs dry.

do you know how long the pump ran for? if it ran for too long, it could be the pump has been damaged.

if it hasn't been damaged, try flushing approx. 500ml of water through the group and see if things improve.


----------



## Jimble101 (12 mo ago)

many thanks! unfortunately hard to say how long the pump ran for. this was the work of a spirited young family member that ran the machine while the parents were looking the other way.

but for sure some air got into the boiler as when I lifted the group lever there was an air 'belch'

having run more water through the machine, the brew pressure is fixed at 4-5 bar, steam pressure reaches up to 2 bar max as normal.

should I understand that I should continue to run water through the machine, perhaps give it a bit of time, then conclude that the pump has been damaged and seek to replace...?


----------



## Jimble101 (12 mo ago)

and perhaps already to ask, is replacing the pump an option for a reasonably handy DIY-er?


----------



## Jimble101 (12 mo ago)

with a blind portafilter it reaches 10 bar


----------



## MediumRoastSteam (Jul 7, 2015)

Jimble101 said:


> with a blind portafilter it reaches 10 bar


 Then you have no problem. All you need to do is grind finer? Aim for a shot of 36g within 30 and 35 seconds.


----------



## Jimble101 (12 mo ago)

thanks yes my bad also the grind settings were wildly changed.

now the brew pressure is at 7 1/2 bar, which is definitely a bit lower than usual.

still a bit of trapped air?


----------



## MediumRoastSteam (Jul 7, 2015)

Jimble101 said:


> thanks yes my bad also the grind settings were wildly changed.
> 
> now the brew pressure is at 7 1/2 bar, which is definitely a bit lower than usual.
> 
> still a bit of trapped air?


 As I said, I don't think you have a problem. If it's going to 10bar with a blind basket, then the pressure can go to 10 bar - which is correct.

If it doesn't when you brew coffee, grinder finer. the only thing offering resistance in the brew circuit is the expansion valve (which will open at 10 bar as you found out) or the coffee puck. If the pressure is at 7 bar, then it's because of your coffee puck not offering enough resistance.

Maybe you should shot a video of what you are describing so people can help?


----------



## Jimble101 (12 mo ago)

thanks for the advice - indeed all seems to be back to normal now!


----------

