I created an central heating installation with 2 zones as shown in the diagram below.
Zone 1 is for the ground floor while zone 2 is for the first floor. The return pipe from zone 2 merges with the one from zone 1 through a tee when reaching the ground floor.
The issue I have is when I activate zone 2 only, some of the radiators from zone 1 heat up too as shown in the diagram below (highlighted in yellow):
I believe this is happening due to reverse circulation on the return pipe after the tee, as shown with the blue dotted arrows.
I believe I have 2 options to address the issue.
Option 1: installing a check valve at the location shown in the next diagram
Option 2: running the return pipe for zone 2 all the way back to the boiler as shown below
Which option would you use?
Option 1 is obviously the cheapest and quickest, but is there any advantage / inconvenient using either option?
Thanks!
Zone 1 is for the ground floor while zone 2 is for the first floor. The return pipe from zone 2 merges with the one from zone 1 through a tee when reaching the ground floor.
The issue I have is when I activate zone 2 only, some of the radiators from zone 1 heat up too as shown in the diagram below (highlighted in yellow):
I believe this is happening due to reverse circulation on the return pipe after the tee, as shown with the blue dotted arrows.
I believe I have 2 options to address the issue.
Option 1: installing a check valve at the location shown in the next diagram
Option 2: running the return pipe for zone 2 all the way back to the boiler as shown below
Which option would you use?
Option 1 is obviously the cheapest and quickest, but is there any advantage / inconvenient using either option?
Thanks!