Dacres was promoted to commander on 28 August 1834, being appointed to his first command, the paddle sloop on 16 August 1836. He was promoted to post-captain on 1 August 1840 and duly relinquished command of the "Salamander" on 15 September 1840. He was briefly appointed to command in 1847, before taking over command of the 120-gun first rate , from 16 November 1847. The "St Vincent" was at that time the flagship of Rear-Admiral Sir Charles John Napier, commander of the Channel Fleet. Dacres took command of the 50-gun frigate on 28 September 1849, commissioning her at Portsmouth and joining a Squadron of Evolution. He commanded the "Leander" until 3 June 1852, when he was shifted to the screw-propelled second rate . He took command on 8 June 1852, commissioning her at Plymouth and sailing her to Lisbon. She spent 1853 as part of the Channel squadron, then with the outbreak of the Crimean War Dacres sailed to the Black Sea in 1854 to support operations. Dacres remained in command until 22 November 1854, when he was succeeded by Acting-Captain Leopold George Heath. He was appointed a Companion of the Bath on 5 July 1855, and on 30 April 1857 he was among the British officers who fought in the Crimea who received permission from Queen Victoria to accept the award of Officer of the Légion d'honneur.