Question for the experts

[lenny]

Hi,
On a vented central heating system What is the maximum length running horizontally from the gravity flow and return pipes to the cylinder coil?

Does that make sence? Or whats the maximum distance the cylinder can be from the boiler? The boiler on the ground floor and the cylinder on the first floor.

Thanx
😕

 

[bobpape]

Thats a funny question considering the event of pumped systems and zone valves
negated the need for concern,
But the effectiveness of gravity primary is related to pipe sizing, consider it works because of a phenomena called "thermo syphoning"
Boiler heats water..water expands get lighter.. rises..sheds heat to domestic water...
cools gets heavier... drops back to boiler..

I have installed cylinders 8m from boiler on same level and it worked
If the cylinder
is above the boiler then I believe the inherent velocity in the vertical flow helps to speed it up,

Anyway if it did not work you could always fit a pump, and control it via the
cylinder thermostat, and perhaps a zone valve.

 

[Rydell]

Correct and good answer to the above question!