When water goes cold and won’t run hot, 24 hour commercial plumbing service is probably needed. There are some simple fixes. For example, the pilot light may be out on a gas appliance. You may need to contact your utility provider. If the problem is that the pilot light goes out quickly, a gas control valve or the rmocoupler may be malfunctioning. Trust professionals with these types of issues. If the problem is that there isn’t enough hot water, there are various potential reasons. The volume of available hot water could be decreasing due to sediment buildup at the bottom of the water heater tank. The thermostat could be on the fritz. Another reason for not having enough hot water could be that the dip tube is damaged. The plastic dip tube directs cold water to the bottom part of the tank. If the tube breaks or cracks, cold water can leak into the top of the tank and flow out instead of the hot water, prompting you to call for 24 hour commercial plumbing service.