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.