OK,
Here's a pic of the bottom of the syphon where you can see that the 3/4" iron to the syphon and the 3/4" copper to the bottom of my hot water tank are separated by one 3/4" brass ball valve.
When I open this valve, water comes out the bottom of my Hot Water tank and straight into the boiler feed lines to the outside jacket of the syphon.
So, I just have to open the valve for about a minute, to top up my boiler which could be anywhere on my property, from the nice warm comfort of my basement!
The 3/4" iron line has a screen clean out in-line and the 3/4" copper line has a one-way valve in-line to prevent boiler water from moving backwards into my domestic hot water tank!
The orange Kytec line you see is where my Wood Doctor boiler water normally feeds in to the bottom of the syphon!
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