초록 ▼

A system is described for use with a hot water supply for hotels, apartment buildings and similar multi-unit structures, which controls the temperature T1 of water at the outlet of a water tank to make it close to a desired temperature DTEMP that is low during times of low demand to save energy and

A system is described for use with a hot water supply for hotels, apartment buildings and similar multi-unit structures, which controls the temperature T1 of water at the outlet of a water tank to make it close to a desired temperature DTEMP that is low during times of low demand to save energy and which is high at times of high demand to assure adequate hot water at all times. The desired temperature at the tank outlet, DTEMP, is adjusted according to the sensed demand for hot water during an immediately preceding period of given duration, such as 45 minutes. The circuitry is used in parallel with an existing Aquastat on a commercial tank type water heater.

대표청구항 ▼

In a hot water heating system which includes a water tank having an inlet for receiving cold water and an outlet for delivering hot water, and a heater which can be turned to on and off states to heat and not heat water in said tank, the improvement comprising: a first circuit which includes a senso

In a hot water heating system which includes a water tank having an inlet for receiving cold water and an outlet for delivering hot water, and a heater which can be turned to on and off states to heat and not heat water in said tank, the improvement comprising: a first circuit which includes a sensor that senses the water tank temperature, said first circuit constructed to generate a signal representing said tank temperature T1; a second circuit which senses the state of said heater and generates a signal representing the state of said heater; a third circuit having a portion settable to a minimum tank water temperature Tmin, a memory circuit portion coupled to said second circuit and storing a quantity substantially representing the proportion of time during an immediately preceding period of time that said heater was on, and a portion that generates a signal representing a desired temperature DTEMP substantially equal to said minimum temperature Tmin plus a quantity multiplied by the proportion of time during said preceding period that said water heater was on; a fourth circuit which compares said signal representing said tank temperature T1 to said signal representing DTEMP, and which urges said heater to an on state when DTEMP is above T1.