[0.18.35] Cannot connect system with different fluids - heavy oil tanks

[Vurmashin]

I cannot connect heavy oil tanks that are both half full with heavy oil either with underground pipes, normal pipes or pumps, the error I get is - Cannot connect system with different fluids.
Light oil, crude oil and gas work fine, as well as heavy oil connections of a same type on other places on the map.
I could mail you the savegame if you'd like, its quite huge at 100 Mb.

[Loewchen]

One of those fluid systems has multiple fluids in it.

[Vurmashin]

How is that even possible?

[Vurmashin]

I only see heavy oil listed in any of those tanks, and only heavy oil piping is connected to it.

[Loewchen]

Post a link to a save that shows that issue with neither systems having multiple fluids.

[Vurmashin]

https://tinyurl.com/factorio-err-heavyoil
the tanks that cannot connect are on the right, close to the save point, like the picture, heavy oil tanks to the left connect normally.
I cannot see any fluid mixing at all. I have never seen it in Factorio.
I have added a waypoint named Error!!! that is the location of the error.

[Loewchen]

A click on any of the top tanks shows that the system contains steam...

[Vurmashin]

Thank you, I did not know that.

[valneq]

How is that even possible?

It can easily happen sincet he fluid mixing prevention was simplified / relaxed, more information here:
https://www.factorio.com/blog/post/fff-351