BTW, isobaric volumetric specific heat of aluminum is about half that of water which is still considerable- and nothing rules out the ottoman containing a reservoir of water. Alan Fletcher wrote up the experiment at the time and while he said he thought it indicated anomalous heat, he also noted:
The Secondary Output thermocouple was attached to the brass head of the heat exchanger manifold, and could possibly have been directly affected by the temperature of the incoming steam/water flow.
It should have been placed in the outlet tube, well away from the Primary Input.
The biggest calorimetric problem is that a counter-flow heat exchanger was used, and the position of the "output" thermocouple was close to the input (steam) flow, through a brass block, so the output temperature measurement may be unreliable.
Misplacement of thermocouples seems to be a trademark Rossi move and is probably how he originally fooled Focardi and Levi with the first ecats. Of course I can't *prove* that the misplacement was calculated and deliberate but then again, remember, IH could not make ecats work and neither could anyone other than Rossi or the Swedes with Rossi heavily involved.