Rads getting hot when just CH is on. Always been this way. Think I may be getting reverse flow.
S config. Trad non-combi boiler. Header tank. Boiler is a Stelrad Mexico.
Pipes run boiler to pump to t piece that splits to hw 2-way zone valve to hw tank one way; and ch 2-way zone valve to rads the other way. Two rad circuits.
When HW on but CH off, pipes hot both sides of both zone valves. Thought HW zone valve stuck on, so replaced CH zone valve. Didn't fix it. Also replaced master thermostat to be sure.
Believe new zone valve working properly, and manual switch indicates ch zone valve closed when it should be. Hence thought reverse flow.
The return from the hwc is often very hot. It joins the return from the rads. This then goes to the boiler (but seems to have another circuit (rads?) joining it on the way. Disappears into a wall at that point, so hard to see. If that's true, suspect I need to move the hwc return to a point after the second rad return.
Am I barking up the wrong tree, or is this a sensible diagnosis?
S config. Trad non-combi boiler. Header tank. Boiler is a Stelrad Mexico.
Pipes run boiler to pump to t piece that splits to hw 2-way zone valve to hw tank one way; and ch 2-way zone valve to rads the other way. Two rad circuits.
When HW on but CH off, pipes hot both sides of both zone valves. Thought HW zone valve stuck on, so replaced CH zone valve. Didn't fix it. Also replaced master thermostat to be sure.
Believe new zone valve working properly, and manual switch indicates ch zone valve closed when it should be. Hence thought reverse flow.
The return from the hwc is often very hot. It joins the return from the rads. This then goes to the boiler (but seems to have another circuit (rads?) joining it on the way. Disappears into a wall at that point, so hard to see. If that's true, suspect I need to move the hwc return to a point after the second rad return.
Am I barking up the wrong tree, or is this a sensible diagnosis?
