When the days grow chilly, you want – no, you need – a steaming hot shower to get you going in the morning. So if you turn that faucet and wait and wait ... and wait some more for the water to warm up, your day's off to a bad start.

“Why is my shower not getting hot?” you moan. Good question. But it should really be broken down into 2 parts. Let’s look at both, and come up with some answers before you freeze!

1. Why is my shower not getting hot (and there’s no hot water anywhere)?

• Water heater malfunction

 When there’s no hot water anywhere in the house, most probably your hot water heater is not working as it should. If you have a gas water heater, check to see whether the gas lines are closed or pilot light has gone out. (You may be able to relight it yourself, following the manufacturer’s directions on the heater UNLESS there is a smell of gas. In that case, call the gas company immediately, from outside your home.)

In the case of an electric unit, the breaker may have tripped or the heater may need to be restarted. Another possibility is that a leak from your hot water heater has caused a short in its electronics. Make sure your electric water heater is safely off before you make any attempt to inspect it.

• Undersized water heater

Your tank water heater may have temporarily run out of hot water because it’s just too darn small for the needs of your household. A 30-gallon unit, for example, is fine for a single person but will definitely not be up to the task of supplying enough heated water for the multiple showers and appliances used by a big family. (Average usage amounts to 10+ gallons per shower, 8 gallons per clothes washer load, and 6 gallons per dishwasher load.)

Consider replacing your current water heater with a larger capacity model; they are available in sizes up to 80 gallons and have a normal lifespan of 10 years. In the meantime, turn up the appliance’s thermostat to 140 degrees max – and if you don’t already have one, install an anti-scald device or faucet barrier to protect your loved ones.

• Inadequate tankless water heater strength

Tankless water heaters may promise to offer hot water on demand. It’s true that you will be spared the hassle of waiting for a tankful of water to heat up if you’re last in line for the shower.

However, tankless heaters come in various strengths, measured in gallons per minute (GPM). Overtax this capacity and you’ll be left, once again, wondering, “Why is my shower not getting hot?”

The simple, cheaper solution is to install low-flow showerheads and water-saving faucets. In the long run, you might want to replace your water heater with a more powerful version.

2. Why is my shower not getting hot (when there’s hot water everywhere else in the house)?

• Incorrect anti-scald setting

Your anti-scald device (AKA temperature-regulating mixing valve) is an important safety feature, designed to prevent accidental scalding when, for instance, your toddler turns the hot water way, way up. However, if the device is set incorrectly, the result is water that’s way too cold.

Adjusting anti-scald settings on digital or smart showers is easy, but did you know that even resetting a manual device is a fairly simple DIY task? Just follow manufacturer’s instructions for your shower model. CAVEAT: Keep children safe; install a barrier or lock to prevent tiny hands from playing with the faucet. 

• Shower mixing valve problem

The shower mixing valve works to blend hot and cold water, controlling the temperature of your shower. If this valve has been positioned incorrectly or if it’s worn out or broken down completely, you are likely to end up with an ice cold shower.

Shower repair for the mixing valve is tricky – it involves taking apart the shower fixtures. Time to hire an expert in water heater replacement and repair.

Laura Firszt writes for networx.com.