A thermocouple for measuring a temperature within a reaction chamber comprising: a sheath having a measuring tip and an opening; a support member having a first distal end and an opposing second distal end; a first wire received within said support member ; a second wire received within said support member , said second wire being spaced-apart from said first wire within said support member ; and a spacing member comprising a base comprising a first surface and an opposing second surface, a first protruding portion extending from said first surface, and a second protruding portion extending from said second surface, wherein the first protruding portion is configured to be received within and secured by the sheath and comprises a first portion of a first aperture extending therethrough and configured to receive the support member , and wherein the second protruding portion comprises a second portion of the first aperture , a second aperture intersecting the second portion of the first aperture and configured to receive the first wire and the second wire , and a third aperture substantially aligned to the first aperture along a longitudinal axis of the spacing member and configured to receive the second distal end of the support member , wherein the second aperture is between the first aperture and the third aperture , wherein the support member freely translates along an axis within the first and third apertures during thermal expansion to allow said support member , said first wire , and said second wire to independently thermally expand and contract, and wherein the first wire and the second wire exit the second aperture and form u-shaped loops adjacent opposing sidewalls of the spacing member . a sheath having a measuring tip and an opening; a support member having a first distal end and an opposing second distal end; a first wire received within said support member ; a second wire received within said support member , said second wire being spaced-apart from said first wire within said support member ; and a spacing member comprising a base comprising a first surface and an opposing second surface, a first protruding portion extending from said first surface, and a second protruding portion extending from said second surface, wherein the first protruding portion is configured to be received within and secured by the sheath and comprises a first portion of a first aperture extending therethrough and configured to receive the support member , and wherein the second protruding portion comprises a second portion of the first aperture , a second aperture intersecting the second portion of the first aperture and configured to receive the first wire and the second wire , and a third aperture substantially aligned to the first aperture along a longitudinal axis of the spacing member and configured to receive the second distal end of the support member , wherein the second aperture is between the first aperture and the third aperture , wherein the support member freely translates along an axis within the first and third apertures during thermal expansion to allow said support member , said first wire , and said second wire to independently thermally expand and contract, and wherein the first wire and the second wire exit the second aperture and form u-shaped loops adjacent opposing sidewalls of the spacing member . <EOS>