I am working on a project and I have some questions about setting up a passive heating system (thermosiphon) with a heat exchanger. I will have a main boiler with a coil of copper tubing inside. This coil will be my heat exchanger. It will then continue to pass through an object which is the target of the passive heating cycle. My question is about the placement location of the coil's ends. Please see the attached system drawings. Will either of these work? Also, to clear up the "T" in the lower-left: for the purposes of discussing the thermosiphon loop, you can pretty much ignore this. Check valves will be in place to ensure the return goes back into the exchanger coil. Thanks in advance for the help]1
In the broad sense your question is asked I'd say yes, this will work either way.
Two things to consider that could be an indicator for you to go with #1 or #2:
Depending on the actual design, the isolation of the copper coil in between the heater and the item to be heated you might try and keep the distance as short as possible to reduce heat loss. So this might favor #2
On the other hand #1 may be favorable if you need to increase heat transfer in the tank and want to increase the surface area for heat transfer.