If your heater is gas, you will need to see if the pilot light is on. If not, it needs to be relit. You can do this yourself (follow the water heater manufacturer's directions), or your public service company can also relight the pilot for you.
If the pilot seems ok, check the thermostat. You can turn on a hot water tap somewhere in your home--leave it running for a few minutes. The thermostat should detect a need for hot water, and the burner should light automatically. If it doesn't, the thermostat is probably defective. A professional can replace it.
Is the water hot enough at first, and then gets cooler? If that's the case I would ask have you flushed out the tank recently? Sediments that build up in the water heater tank can reduce both capacity and efficiency. Flush you water heater tank. Follow the manufacturer's instructions. Your water heater should be flushed at least annually to remove sediments in the tank. Your heater will last longer and be more efficient this way.
If the pilot seems ok, check the thermostat. You can turn on a hot water tap somewhere in your home--leave it running for a few minutes. The thermostat should detect a need for hot water, and the burner should light automatically. If it doesn't, the thermostat is probably defective. A professional can replace it.
Is the water hot enough at first, and then gets cooler? If that's the case I would ask have you flushed out the tank recently? Sediments that build up in the water heater tank can reduce both capacity and efficiency. Flush you water heater tank. Follow the manufacturer's instructions. Your water heater should be flushed at least annually to remove sediments in the tank. Your heater will last longer and be more efficient this way.