Question regarding operation of heater core in W124 vs W114
 

I noticed that the W124 has the auxiliary electric water pump and seems to accelerate hot coolant flow from the radiator to the heater core...

The W114 I am working on does not seem to have this kind of system.

Do I have this right?

(There is always flow of coolant from the radiator to the heater core in the W124 at all times, only when the operator of the car turns on the A/C system does the auxiliary water pump switch on thus increasing the flow rate of said coolant...?)

Nah
 

If that we're the case,you'd Freeze Your Wallet Off in January on I-285.
(I believe that Auxiliary Water Pump is on all the time the Key is On.)
The Mono-Valve regulates how much ,If Any, HOT water gets to the H.C.

They installed the Auxiliary Water Pump to "Make Up" more Heat availability
at Idle/Super-Low engine speeds (the Mechanical Water Pump is subject to
engine RPMs)...Look at all the Damn places the coolant has to travel on a
W124 chassis...Easily an extra 100Ft. in addition to cooling the engine.
(Distance/Friction=loss of flow rate)