Treato found 16 discussions about Cold Symptoms and Cats Allergy on the web.
Best Answer: When the toilet is flushed, the toilet is robbing pressure from the shower, which is usually close to the toilet. As the COLD water pressure goes down from the toilet flush, the HOT water pressure is higher, therefore the water gets hotter as the COLD pressure goes down.
If there are multiple appliances using hot water when you are taking a shower, you will run out of hot water. Dishwashers, washing machines and even hand washing at the sink use enough hot water to make your shower quickly run out of hot water.