Replace your old hot water heater with a new high-efficient one
Water heating can account for 14%–25% of the energy consumed in a building. An old or insufficiently sized water heater may be using energy inefficiently and causing unnecessarily high heating bills. Finding the most efficient water heating system for a building is a crucial part of running a building efficiently as is ongoing maintenance of existing domestic hot water heaters to keep existing equipment at peak operating efficiency and extend the lifetime of equipment.
A new water heater can be a cost effective investment for multifamily buildings. If the current water heater is older than 10 years, it may be operating at 50% or less efficiency and it should be replaced. When considering the purchase of a new water heater one should considered size, cost, fuel type and efficiency. See the link below to determine what water heater may be right for your building.
If replacing the water heater is not necessary then consider retrofitting your water heater to combat standby or ambient heat loss. Utilizing timers or off-peak water heating methods can greatly reduce energy consumption for some water heaters.