Heating older destroyers for Arctic convoys

Were older convoy destroyers refitted with internal heating, and did it affect their performance?

Yes. The main requirement was keeping machinery and weapons ready in the cold, with little effect on ship performance; heating crew spaces also helped health and morale.

Older destroyers received internal heating, with machinery readiness as the first requirement. Guns and ammunition needed to remain usable even when they were not operating continuously. Crew-space heating also helped morale and health in cold, damp conditions. The power demand was small compared with propulsion, so the heating made little difference to the destroyer's performance. Suggested arrangements included a steam shunt near the condenser and the use of waste heat.