Thermal Simulation doesn't finish

[TRPower]

I am attempting to model heat transfer from a set of pipes with a surface temp of 1100F to a tank with temp 80F.

I have set the initial temps of each part to the above temps.
I have also set up radiation and convection on the 1100F surface.

I am using the Direct Sparse Solver, however it is stuck on a loop.
The total completion bar will reach 99.9/100% and then reset to about 98%.

The tasks occurring are Decomposition of conduction matrix, and establishing a stiffness matrix.

Its been 1.5hrs and I'm not sure whats going on

 

[321GO]

I noticed "strange" behavior on time-dependent study's in the past when the mesh was too coarse.