The simplest reason could be that the capacity of your hot water heater is not enough to supply the demand in the household you're living in. The solution is simple, just get a bigger appliance fitted.
But if you believe your water heater is big enough and that If you've already gone through the electricity supply troubleshooting, the lack of hot water may come from another source. The most common ones being:
Very often thermostats can be set fairly low with the objective to save energy and money. But with that comes colder water. Try setting the thermostat to a higher temperature.
If the above fails, you may have a faulty thermostat which will need replacing.
A conventional electrical water heater has two heating elements, one upper and one lower. If you're thermostat is not faulty maybe one of the elements is no longer working. Electrical heating elements do wear out and need to be replaced every so often.
"This is often caused by an overheated tank. Most of the time it means your thermostat is faulty and will need replacing.
It is also possible that some of the wires connected to the heaters have become loose."
"This may vary from one manufacturer to the other but is generally advice to replace your electrical water heater every 8 to 12 years
If you start noticing leaks at the base of the appliance don't wait too long before considering a replacement"
Like everything else we strongly advice you get your appliance maintained regularly. This will not only extend the life of your water heater in the long run and save you some money, but it will also be safer.
Excel Electricians LTD
37 Edendale Rd
Tel: 07947 194448
Open: Monday-Sunday 24/7