Thermostatic mixer or mixer - question about the principle of operation and reco

Question

I am considering a choice for the sinks at home. I have thermostatic mixers on the bath and in the shower, but at the sinks I think about the mixer (it's probably a three-way valve, if I'm not mistaken). Can someone explain the difference in action? I found on the net description of the...

Plumpi · Accepted Answer

tc - hot water inlet temperature
tz - cold water temperature at the inlet
tw - outlet water temperature

The thermostatic mixing valve maintains a constant outlet temperature, regardless of the inlet water temperature. The condition for the correct operation of such a valve is that the hot water temperature at the inlet must be equal to or higher than the temperature that we want to obtain at the outlet, and that the temperature of the cold water must be equal to or lower than the water temperature that we want to obtain at the outlet.

Condition:

tz =

Zbigniew Rusek · Accepted Answer

The thermostat in the battery is never electronic, but mechanical - it works on the principle of thermal expansion (a tight vessel filled with gas, which, under the influence of temperature, expands and moves valves; the thermostat in thermostatic heads for radiators and in the cooling systems of car engines works similarly). Many faucets have a lock that prevents the water temperature from turning up to more than the standard 38 degrees without pressing the lock button (so you don't burn yourself). In general, these are very different models of such batteries.

Starkes · Answer

OK - very nicely explained (thank you - he also helped "he went"), but please tell me how it is implemented (that the light source in the bulb is the filament through which
current flows, heats up and glows and emits light).

Otherwise - how does a faucet without electronics know how much hot water to mix with how much cold water?
And possibly damage to the battery can cause burns?

Plumpi · Answer

It is inexplicable and you have to take it on faith ;) The battery has a built-in mechanical thermostat which continuously measures the temperature of the water at the outlet and controls the mixing valve. This works on the principle of thermal expansion. I do not know. Somehow I have not encountered such damage to the battery. Typically, this was a damage that was leaking but not affecting the operation of the thermostat. Some faucet models have an additional built-in element to prevent hot water from flowing out. This is called the safe function. Unfortunately, I do not know the details of the construction of such batteries. Somehow I did not have the opportunity to disassemble them.

serwisant73 · Answer

Standard DHW temperature is max. 55 degrees. you are unlikely to burn yourself with this.

Starkes · Answer

And that's what I meant ... So there is no need to pack in the mixer ... I buy valves and ultimately touchless faucets ... Also went well deserved helped ...

kabee84 · Answer

Buddy, it depends what three-way valve we are talking about ...

There are three-way thermostatic valves (eg Honeywell TM 200), which work in the same way as a thermostatic mixer, ie they mix water to a set temperature. By installing such a valve, e.g. in a boiler room, we have a constant water temperature at all points of consumption and we do not have to invest in thermostatic batteries for individual points ...
Such a valve makes sense.

It is different, e.g. in an apartment, where we cannot connect such a valve ... In this case, we are left with thermostatic batteries.

Starkes · Answer

But I think about such valves (and wrote) - how else do you want to connect it to a contactless battery?

Plumpi · Answer

We did not understand each other. What I described are three-way mixing valves, which is what you asked about. But you meant three-way thermostatic valves. As described by kabee84, it is enough to have one such valve with the appropriate capacity installed in the boiler room.

kabee84 · Answer

A non-contact faucet is often a thermostatic faucet. One does not exclude the other.

Starkes · Answer

Thanks to everyone for the information - for my part, I consider the topic exhausted.

To sum up - if you want to regulate the water temperature and you are not sure about the supply temperature (or the temperature is variable), an ordinary mixing valve is not enough and a thermostatic valve or a thermostatic mixer should be used.

Thermostatic mixer or mixer - question about the principle of operation and reco

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