As a standard immersion heater is 3KW, so it would take 2 hours to heat 100 Litres of water. After an hour and a half, it will only have reached about 53 degrees.....
Symptoms & Signs. Pain in the heel can result from a number of factors. Abnormalities of the skin, nerves, bones, blood vessels, and soft tissues of the heel can all result in pain. Because of walking and daily movement, we are always at risk for injury or trauma to the heel area. Common causes of pain in the heel include blisters and corns. Plantar fasciitis, inflammation of the bowstring-like tissue in the sole of the foot stretching from the heel to the front of the foot, is one condition commonly associated with heel pain.
Plantar fasciitis (say PLAN-ter fash-ee-EYE-tus) is the most common cause of heel pain. The plantar fascia is the flat band of tissue (ligament) that connects your heel bone to your toes. It supports the arch of your foot. If you strain your plantar fascia, it gets weak, swollen, and irritated (inflamed). Then your heel or the bottom of your foot hurts when you stand or walk. Plantar fasciitis is common in middle-aged people. It also occurs in younger people who are on their feet a lot, like athletes or soldiers. It can happen in one foot or both feet.