There are 3 basic types of installations with differing requirements;
1. Domestic hot water cylinder
Standard hot water cylinder installations place the tempering valve near the outlet of the cylinder. Although the hot and cold supplies are balanced
when flowing, when the system is static the hot pressure will build due to expansion which is why domestic tempering valves have a cold check
valve as standard.
Caleffi make two options differentiated mainly by flow rates:
TV5213 (15, 20mm) TV5216 (15, 20, 25mm)
Up to 25 l/min or Up
to 35 l/min or
2 - 3 bathroom dwellings 2 - 3 bathroom dwellings
(mains pressure only) (mains or low pressure versions)
TV5231 Series TV6000 Series
2. Circulating ring main (or centralised hot water system)
Large domestic or commercial hot water systems often have bathrooms and other outlets a long distance from the hot water cylinder. When the
system is static quantities of hot water sit and cool in the pipes over this distance. Consequently the delivery of fresh hot water
when a tap is opened is delayed while the cool water is expelled.
A ring main is a continuous loop that gently circulates tempered water at a constant temperature so every outlet is only seconds away from
fresh hot water.
Caleffi make two options differentiated mainly by flow rates;
Extreme duty with
Min/Max flow rates
20mm 10 to 92 l/min 8 to 172 l/min
25mm 13 to 112 l/min 12 to 220 l/min
32mm 17 to155 l/min 17 to 468 l/min
40mm 25 to 225 l/min 25 to 650 l/min
50mm 33 to 272 l/min 33 to 805 l/min
Note: these valves will work in either a ring main or standard configuration.
3. Point of use
Where ultimate protection is required, such as health care facilities, tempering valves are located very near to ‘the point of use’ e.g. directly
under a hand basin. This style of tempering valve offers extremely accurate and responsive temperature control. Since both the hot and
cold supply pressures can vary independent of each other, point of use valves come standard with hot and cold check valves.
Caleffi’s 5213 Series meets both the Australian and the world recognised UK NHS standards.
TV5213 (15, 20mm)
for systems between 4 and
For high temperature applications such as those commonly found in solar systems, Caleffi produce a high temperature version of both
the domestic 5216 and commercial 5231. These models share the same specification as the standard models but allow for the input of
hot water up to 100ºC.
If you need help designing a high demand hot water plumbing system or any general system design advice click here to contact our tech team.