Coolant Regulator Valve: 4/2-Way

Hi there,
The CR 2.0L R4 engines with codes CJCA...CJCD and others are equipped with a "4/2-way valve with coolant regulator" in the cooling circuit.
The only functional description I can find for it is in the SSP455 document for the TDI engine in the T5.
According to the images in the SSP, the control valve keeps the return flow from the heating system's heat exchanger closed until the operating temperature is reached. This surprises me, because the heater also supplies warm air even when the auxiliary heater is turned off.
Is the description too specific for the T5 engine (CAAx, CCHA), or is it incorrect?
hg
Herbert.

Herbert wrote:

According to the images in the service manual (SSP), the control valve keeps the return flow from the heating system's heat exchanger closed until the operating temperature is reached.

The SSP clearly states that the inlet from the heat exchanger is blocked, which makes absolute sense.

It's true that the images suggest a blockage of the inflow from the water tank, not the outflow or return flow. However, something still seems wrong (or I don't understand it).
The heating circuit runs from the cylinder head to the heat exchanger, then to the valve/thermostat, then to the water pump, and back into the engine block and the cylinder head.
hg
Herbert.

Let's put aside the discussion about the SSP (Sequential Shift Program) for the T5 engine. The description in it seems very specific to the T5.
After a lengthy search online, I found instructions for the A3, A5, and Golf models on how to remove the mysterious valve (excerpts), which show it being cut open. The housing looks similar to the one in the A4 CJCD. Inside the housing, you can see what appears to be a double thermostat, with two opposing closing discs, likely operated by cylinders filled with wax.
Along with the color-coded diagram from the RLF (presumably a repair manual), you'll find that: The coolant flow from the oil cooler, the heater, and the EGR cooler always has an open path. A direct connection from the cylinder head (bypass of the above) closes at some temperature, and a connection from the radiator opens at some temperature.
In the maintenance checklist, there's a step that says "Check coolant regulator" with the following settings: opening start at 92°C, closing end at 107°C. This likely refers to the inlet from the radiator.