A magnetized hot-filament discharge plasma in cylindrical geometry has been created in carbon monoxide gas at 2.8 mTorr cooled to 80 K. Langmuir probe data show electron densities of 3 × 10 8 cm −3 at an electron temperature of 0.020 eV (∼200 K). CO is an effective cooling agent for electrons as a consequence of its dipole moment. The CO is contained within a 10 cm diameter × 1 m long copper liner cooled by liquid and vapor from liquid nitrogen. Primary electrons are emitted from a spiral filament at one end and guided by a magnetic field up to 6 mT. With CO pressures sufficient for electron cooling to 200 K, the plasma density falls with distance from the filament.