Are there signs of a diplomatic crisis outside your bathroom each morning? Several members of the family may be jostling for position as they fight to get access first and jump into the shower. Could this bad-tempered melee be something to do with the temperature of the water and, specifically, the fact that the hot water is in short supply? If so, you need to take a close look at the heater to see whether it can cope with the demand or, crucially, may need to be repaired. What do you need to look for?
If the grandparents have recently moved into the home and now occupy an annex, then this increase in family size may have overwhelmed the heater. You need to reassess its size and see if you need to upgrade, as this may be the root of your problem. However, if the heater is also more than a decade old, then it may be due for a replacement anyway. Heating elements and thermostats may start to malfunction at this stage.
Start by looking at the outside of the tank and check the thermostat. If it is set to a reasonable temperature and you are still not getting enough hot water, then this component could be faulty and will need to be repaired or replaced.
Within the tank is a mechanism that helps to push cold water down towards the bottom so that it can be heated effectively and sent through the pipes. This tube may be damaged, and if so, it will need to be replaced.
If you can hear some clicking, banging or rumbling sounds in the morning as the heater starts to warm up, then this is a sign of excess sediment. This can happen when rust combines with other impurities to form a layer on the bottom of the tank. As the water starts to boil, the sediment will start to move around and vibrate.
If you need even more attention, you will need to call in an electrician to help with hot water repairs. They may be able to repair the heating element or the thermostat, make sure that the dip tube is restored to its full functionality and get rid of any sediment that has accumulated on the bottom of the tank. In the meantime, try to maintain law and order outside the bathroom each morning and assure everyone that help is on the way!