You need to reduce the water temperature to prevent scalding.... but at temperatures below 60ºC, there is risk of legionella bacteria growth

- It takes 1,5–2 minutes to achieve a scalding injury in 52°C hot water.
- At 57°C it takes 10 seconds to get scalding injuries.
- 60°C hot water gives scalding injuries of third degree in less than 3 seconds.

The 1…6 marking on the knob is an indication of mixing temperature setting steps of the valves temperature range. The temperature step between every setting is approximately 4°C / 5°C.

However, to set the mixing temperature in accurate way we need to secure flow volume above 4l/min for VTA300 series, and above 9l/min for VTA500 series, and measure the temperature in a point of use for more than 60s.

The valves should be selected based on the needed water flow, application area and system conditions, not by pipe size.

ESBE has created quick guides to make selection easier, and below you can find two different tables. 

First table speaks about the application area, and the second one about the Kvs value in several applications under specific conditions.

For more information please contact customer service.

ESBE has a product for systems with hot water circulation called VTR300, more information is available on the product page.
You can also use VTA320 or VTA520, depending on the flow capacity needed. You should never use a VTA310 in this type of applications.

The VTD300 is a thermostatic diverting valve developed for these applications. You should not use a VTA300. If you need higher flow capacity the VTA500 series can be used as a diverting valve.

To get the right tap temperature you need:

1. A minimum flow volume 4 l/min for all VTA300, and 9 l/min for all VTA500 series.
2. A minimum temperature change ∆t of 10°C between the hot water supply and the set mixing temperature.