Honeywell THX9321R5000 is my first choice thermostat

It should be specially pointed out that the current mode setting the thermostat sensor for 2 to prejudge the valve lift on the saddle: 0,43-0,45 mm in liquid, gas and condensate at 0,56-0,58 mm. It follows from this, it is important to ensure high purity of the coolant in the heating system, equipped with a Honeywell THX9321R5000 thermostat to avoid contamination. According Honeywell, this requirement is more urgent because of the danger of pollution “bypass” the mounting openings adjust Honeywell THX9321R5000 thermostats for two-pipe systems than constantly changing during operation and therefore capable of a certain degree of self-cleaning of the gap between the rod and the valve seat.