Solid fuel boiler, header tank and heat exchanger

[ecurbrenots]

A question to clear things in my mind, i want to fit a solid fuel Rayburn in France, it presumably needs to be an open system for safety but i have the following problem. The house has 3 stories but i can only get the header tank on the 2nd storey which means Rayburn on ground, hot water cylinder on first and header tank on floor 2. However i want to have radiators on floor 3. The Cylinder will be gravity fed and the central heating will be pumped. The only way i can see i can achieve this is to have a heat exchanger on the gravity circuit to heat the pumped circuit or is there an easier way to achieve this without having the pumped circuit pushing the water out of the header tank vent pipe. I have only fitted fully pumped before and while this will be professionaly installed i want to know what options are available so i know i am not being led up the garden path.

Many thanks in anticipation

 

[Norcon]

Yes just fit a plate heat exchanger on the primary flow and wire the primary/secondary circulators in series.
Then the ch can be sealed.

 

[Onetap]

Yes just fit a plate heat exchanger on the primary flow and wire the primary/secondary circulators in series.
Then the ch can be sealed.

I think Norcon means fit a heat exchanger on the existing CH system. The secondary side of the plate heat exchanger is then the heat source for the heating serving the second floor, which is then a separte sealed system with its own filling loop, expansion vessel and pressure relief valve. Primary and secondary pumps that run simultaneously. The primary/Rayburn side remains open vented.

"The CH can be sealed" could be (mis)understood as meaning the Rayburn could be a sealed system.

 

[ecurbrenots]

Many thanks for your answers , what size heat exchanger (recommended make and model if possible) should I use to ensure sufficent heat transfer from the primary gravity system serving the hot water cylinder to the sealed pumped central heating circuit.

 

[Norcon]

This will be ample though you can check your application with them...
http://www.eco-equipped.com/brazed-plate-heat-exchanger.html

Not crazy money either and a reputable make made in Germany.
If you go to the likes off bss they won't sell you a heat exchanger without relinquishing their vested interests as middle men and you'll be charged at least three times that price. Been there and got the T shirt.

 

[Onetap]

.........should I use to ensure sufficent heat transfer from the primary gravity system serving the hot water cylinder to the sealed pumped central heating circuit.

The gravity circulation won't push the water through a plate heat exchanger, it needs a pump on the primary side. You really need to find someone to provide sketches of this system.