In two-pipe heating systems for the design parameters of coolant 95-70 ° C is usually MNR = 25-75 kg / h, while foreign recommendations for these parameters (75-65 ° C) the same flow rate of 50-150 kg / s Honeywell YTH5320R1000 Wireless Thermostat Kit .
Despite the new European recommendations for reducing the calculated coolant temperature and an increase in consumption of the standard EN 215 regulates the nominal coolant flow rate of 36 kg / h. Therefore, in general, testers useful for designers to give the values ? and S at different coolant flow rate, for example, at 36 and 90 kg / h, since the values of ? and S, as indicated, are not constant because of the actual non-quadratic dependence of Dp on the MPR. At the same time, if the difference between ? and S at different coolant flow is not so much, they can be averaged to determine when the coolant flow rate, for example, within 60-72 kg / h (when equipped with heaters Honeywell YTH5320R1000 thermostats).
