Temperature of water supply to the shower?

I have secondary progressive Multiple Sclerosis and have a lowered immune system, so i have a scenario and question.

I live in a new council apartment in West Yorkshire and my water temperature is limited through the taps and shower. My kitchen tap is 45.8°C, the bathroom tap is 43.6°C, and the shower is 39.8°C. The shower is what really concerns me but the council just will not agree to raising the temp. I have a Potterton Pro Max Combi-boiler and obviously don’t have any water storage but this is my concern and I would like your opinion please.

My concern is that even though water temp through to the shower control unit is probably around 43.6°C from the Thermostatic mixing valve it only then produces the 39.8°C water which is the ideal temp for Legionella to thrive. My point has been two fold. When I go on respite for 4 weeks, because of the low temp it becomes a possibility that Legionella can breed and infect me. Then because the temp will NEVER be hot enough to kill off any bacteria it will just grow and grow.

Am I correct in making this assumption? I just have to be ultra-cautious because of my lowered immune system and something like this could be really bad for my wife and myself.


Your assumptions are not quite correct.

Please review our website FAQs and do a search on the top right hand of the Home Page.

Showers are not a major mode of transmission. Setting your thermostat higher may not be effective if Legionella is already in your home water supply.

A simpler more effective solution is given in the Publications.

Legionnaires’ disease contracted from patient homes: The coming of the third plague?

The solution to your question is on page 704, second to last paragraph.