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.
A remedy exists to the hot water flushing problem. The most obvious is not to flush while others are taking a shower. But you can also invest in a faucet monitor that will keep up with the supplied pressure from the hot and cold side in your shower.