why does only one out of my three toilets have a siphon break?

[kflod]

Hi,
I have a 54 MY and I am currently upgrading from failing Galley Maids heads to new Planus heads.
I am looking at the plumbing diagram and find that only the master head has a siphon break, the two other do not have any. Why is that? As far as I can see all toilets/pumps are approx equal to the water line - at least all pumps are well below the water line. Shouldn't they all have siphon breaks?

 

[Photolomy]

You might want to look at this thread...

https://www.samsmarine.com/forums/archive/index.php/t-7557.html?

Maybe a modification due to relative positioning of the pumps and the heads.

 

[kflod]

You might want to look at this thread...

https://www.samsmarine.com/forums/archive/index.php/t-7557.html?

Maybe a modification due to relative positioning of the pumps and the heads.

Thanks, you're right - the master head pump was located higher then the others. It keeps loosing prime - or I'll need to replace the waste end components in the pump.