JP2932165B2 - How to measure remaining hot water - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for automatically filling a bath tub and for measuring the amount of remaining hot water in the bath tub, which is used in a heating circulation system such as a bath water heater having a reheating function.

[0002]

2. Description of the Related Art When a bathtub is automatically filled with hot water, if there is remaining hot water in the bathtub, it is necessary to supply the remaining amount of hot water to the bathtub by subtracting the remaining hot water amount from the fixed capacity of the bathtub. Conventional bath water heaters use a circulation pump to circulate hot water in a bathtub to a heat exchanger, and heat the heat exchanger directly using a heat source such as a burner.Therefore, the amount of heat generated by the heat source and the heat exchanger The amount of heat transmitted to the circulating hot water is determined from the efficiency of the hot water, and the remaining hot water amount can be known by detecting the temperature rising speed of the remaining hot water in the bathtub by a temperature sensor. That is, if the amount of heat transferred to the hot water is constant, the temperature rises faster as the remaining hot water amount is smaller. In this case, the circulation flow rate of the hot water circulated to the heat exchanger by the circulation pump is not necessary for calculating the remaining hot water amount.

[0003]

When the heat source is used in conjunction with the heating of the hot water for other purposes such as heating other than the heating of the hot water in the bathtub, the hot water in the bathtub may not be guided to the position of the heat source. In some cases, a heat medium is interposed, the heat medium is first heated by a heat source, and heat is transferred from the heat medium to hot water in the bathtub using a heat exchanger. However, when the heating medium is used for a plurality of applications in this way, depending on the usage of other applications,
The ratio of the amount of heat transmitted to the hot water in the bathtub out of the amount of heat transmitted from the heat source to the heat medium fluctuates, and the remaining hot water cannot be calculated.

[0004] In view of the above problems, an object of the present invention is to provide a method capable of measuring the amount of remaining hot water in a bathtub regardless of the usage status of other uses.

[0005]

In order to achieve the above object, the present invention provides a heat exchanger for heating hot water in a bathtub with a heat medium heated by a heat source; And a circulation pump for circulating water, wherein the temperature of each hot water at an inlet where the hot water in the bathtub enters the heat exchanger and an outlet where the hot water returns to the bathtub and the circulation pump are provided. Determining the amount of heat transferred to the hot water circulated through the heat exchanger from the circulating flow rate of the hot water circulated in the step, and obtaining the amount of the hot water from the transferred heat and the temperature rising speed of the remaining hot water in the bathtub. And

In addition, the apparatus has a first heat exchanger for heating hot water in a bathtub with a heat medium heated by a heat source, and a second heat exchanger used for purposes other than heating the hot water in the bathtub. , First
A method for measuring the remaining hot water in a heating and circulating system including a circulating pump that circulates hot water in a bathtub to a heat exchanger of
In a state in which the heat medium flows to both the first heat exchanger and the second heat exchanger, the hot water in the bathtub enters the first heat exchanger and the hot water flows at the outlet where the hot water returns to the bathtub. From the temperature of the hot water and the circulation flow rate of the hot water circulated by the circulation pump,
The amount of heat transferred to the hot water circulated through the heat exchanger is determined, and when the heat source is heating only the first heat exchanger, the heat value of the heat source and the preset efficiency of the first heat exchanger are determined. First from
The amount of heat transferred to the hot water circulated through the heat exchanger is obtained, and the amount of the hot water is obtained from the amount of transferred heat and the rate of temperature rise of the remaining hot water in the bathtub.

In the above invention, when the heating medium is used for a purpose other than the heating of the hot water in parallel with the heating of the hot water, the supply of the heating medium to the other uses is temporarily stopped. Stop,
The circulation flow rate is previously calculated from the temperature of each hot water at the entrance where the hot water in the bathtub enters the heat exchanger and at the outlet where the hot water returns to the bathtub, and after the suspension is released, the calculated circulation flow rate is used. It is characterized in that the amount of transferred heat is obtained.

[0008] The amount of heat transferred to the hot water can be determined from the heat value of the heat source and the efficiency of the heat exchanger interposed between the heat source and the hot water. However, in a system configured to be able to heat a plurality of heat exchangers with a heat medium, when the heat medium is flowing through one heat exchanger, the amount of heat transferred to the hot water is determined as described above. However, the amount of heat cannot be obtained in a state where the heat flows through a plurality of heat exchangers. Therefore, the present invention relates to the data on the heat receiving side. I asked for it.

In determining the amount of heat transferred to the remaining hot water, it is necessary to know the circulating flow rate of the hot water by the circulating pump, but the circulating flow rate is easily affected by the flow resistance of the hot water. Even if a standard circulating pump is used, the circulating flow rate will be different if the piping conditions are different. Therefore, although the actual circulating flow needs to be measured after the piping is installed, if a mechanical flow meter such as a water wheel type is provided in the middle of the piping, the flow cannot be accurately measured due to garbage in the hot water. Therefore, the supply of the heat medium to the second heat exchanger is temporarily stopped, and all the known heat supplied by the heat source is given to the remaining hot water so that the hot water in the bathtub enters the heat exchanger. The circulation flow rate of the circulation pump was determined from the temperature difference between the hot water temperature at the outlet and the hot water temperature at the outlet where the hot water returned to the bathtub. That is, if the amount of heat given is constant, the temperature difference becomes smaller as the circulation flow rate increases. Then, the remaining hot water amount is obtained using the circulation flow rate of the circulation pump thus obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference numeral 1 denotes a bathtub having a hot water 11 therein. The hot water 11 is heated by the burner 2 which is a heat source. The water circulated by the heat medium pump 31 is used as a heat medium, and the heat medium is heated by the gas-liquid type heat exchanger 21 to open the on-off valve 31. The liquid is supplied to a liquid-liquid type heat exchanger (first heat exchanger) 3 via the heat exchanger. On the other hand, hot water 11 in bathtub 1
Is configured to circulate in the heat exchanger 3 by the circulation pump 4. The inlet temperature and the outlet temperature of the hot water 11 circulated through the heat exchanger 3 are measured by temperature sensors 41.4 and 41.4, respectively.
2 is detected. Incidentally, the heat medium is supplied to the heat exchanger 3 and not only heats the hot water 11 in the bathtub 1 but also a hot water mat 5 (second heat exchanger) for floor heating in the middle of the circulation path.
It is also used as indoor heating. An on-off valve 31 is provided in a circulation path to the heat exchanger 3, and an on-off valve 51 is provided in a circulation path to the hot water mat 5. When the on-off valve 51 is opened, the heating medium is supplied to the hot water mat 5 to perform indoor heating, and when the on-off valve 31 is opened, the heating medium is supplied to the heat exchanger 3. A hot water filling mechanism 6 is connected between the temperature sensor 42 and the bathtub 1 via an opening / closing valve 61, and hot water heated by the hot water filling mechanism 6 that opens the opening / closing valve 61 is supplied to the bathtub 1. It is configured so that hot water is automatically filled. The opening of the on-off valve 51 may be proportionally controllable, and the temperature of the temperature mat 5 may be adjusted by controlling the amount of the heat medium flowing through the hot water mat 5.

In the above structure, in order to automatically fill with the filling mechanism 6, in order to determine how much hot water is to be added to the bathtub 1 by the filling mechanism 6,
It is necessary to know how much hot water 11 remains in bathtub 1. In this case, first, the amount of heat transmitted to hot water 11 is Q
(Kcal / min) and the temperature rise rate of the remaining hot water in the bathtub is Vt (° C./min), the remaining amount W of the hot water 11
(L (liter)) is expressed by W = Q / Vt (1) from Q = W · Vt. The temperature of the hot water in the bathtub can be detected by the temperature sensor 41 provided on the inlet side of the heat exchanger 3, and the temperature sensor need not be provided in the bathtub.

Since the heat quantity Q varies depending on the amount of the heat medium branched to the hot water mat 5, the circulation flow rate of the hot water 11 by the circulation pump 4 is set to M (1 / min), and the temperature sensors 41 and 42 Assuming that the temperature is T1 · T2 (° C.), the quantity of heat actually transmitted from the heat exchanger 3 to the hot water 11 is obtained from Q = M · (T2−T1) (2).

However, the circulating flow rate M of the circulating pump 4 is easily affected by the pipe resistance and the like, and even when the same pump is used, the circulating flow rate M may differ depending on the pipe state. However, if the circulating flow rate M is not accurately defined as described above, the calculation result itself of the remaining hot water amount W becomes inaccurate. Therefore, the actual circulation flow rate M is determined after the piping of the circulation pump 4 is constructed, and the remaining hot water amount W is determined using the circulation flow rate M. The method for obtaining the circulation flow rate M is to open the on-off valve 31 and close the on-off valve 51 so that all of the heat medium is supplied to the heat exchanger 3. The amount of heat transferred from the burner 2 to the heat medium depends on the amount of heat generated by the burner 2 and the heat exchanger 2
The heat transfer amount in the heat exchanger 3 obtained from the heat amount and the efficiency of the heat exchanger 3 can be obtained as Q, and M can be obtained by substituting it into the above equation (2) together with T1 and T2. . When the circulation flow rate M is determined in advance in this way, the on-off valve 51 is opened, the heating medium is also supplied to the hot water mat 5, and the amount of the heating medium supplied to the heat exchanger 3 fluctuates. As described above, the remaining hot water amount W in the bathtub 1 can be accurately obtained.

The above method can be applied to the above equation (2) whether or not the heating medium is circulated in the hot water mat 5 as the second heat exchanger. In a state where the medium is not circulated and the heat medium is supplied only to the heat exchanger 3 as the first heat exchanger, the heat value ZP of the burner 2 determined from the gas flow rate supplied to the burner 2 is set in advance. From the efficiency μ1 of the heat exchanger 21 and the efficiency μ2 of the heat exchanger 3, the amount of heat Q transferred to the hot water 11 is given by (3)
It can be obtained by an equation. Q = ZP × μ1 × μ2 (3) Although a burner is used as a heat source in the above-described embodiment, another type such as an electric heater can be used as a heat source. Although the hot water mat is used as the second heat exchanger, a hot air fan heater may be used. Further, both the hot water mat and the hot air fan heater are connected and both are used as the second heat exchanger. You may.

[0015]

As is apparent from the above description, the present invention measures the amount of remaining hot water in a bathtub necessary for automatically filling a bath, by measuring the amount of heat transferred to the remaining hot water. Can be performed accurately.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 bathtub 2 burner 3 (liquid-liquid type) heat exchanger (first heat exchanger) 4 circulation pump 5 hot water mat (second heat exchanger) 21 (gas-liquid type) heat exchanger 31 opening and closing Valves 41 and 42 Temperature sensor 51 On-off valve

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Nakajima 2-26, Fukuzumi-cho, Nakagawa-ku, Nagoya, Aichi Prefecture Inside Rinnai Corporation (72) Inventor Hiroyuki Yamada 2-26, Fukuzumi-cho, Nakagawa-ku, Nagoya-shi, Aichi Rinnai (56) References JP-A-3-13758 (JP, A) JP-A-3-204557 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F24H 1/00 602

Claims (3)

(57) [Claims] 1. A method for measuring remaining hot water in a heating and circulating system including a heat exchanger for heating hot water in a bathtub with a heat medium heated by a heat source, and a circulation pump for circulating hot water in the bathtub to the heat exchanger. Wherein the temperature of the hot water in the bath tub at the entrance to the heat exchanger and the temperature of the hot water at the outlet at which the hot water returns to the bath tub and the circulating flow rate of the hot water circulated by the circulating pump, A method of measuring the amount of heat transferred to the hot water to be performed, and calculating the amount of the hot water from the amount of heat transferred and the rate of temperature rise of the remaining hot water in the bathtub. 2. A first heat exchanger for heating hot water in a bathtub with a heat medium heated by a heat source, and a second heat exchanger used for heating other than the purpose of heating hot water in the bathtub. Have
A method for measuring remaining hot water in a heating and circulating system including a circulation pump for circulating hot water in a bathtub to a first heat exchanger, wherein a heat medium flows to both the first heat exchanger and the second heat exchanger. In the state, the temperature of each hot water in the inlet and the outlet where the hot water in the bathtub enters the first heat exchanger and the outlet in which the hot water returns to the bathtub, and the circulation flow rate of the hot water circulated by the circulation pump,
The amount of heat transferred to the hot water circulated through the first heat exchanger is determined. When the heat source is heating only the first heat exchanger, the heat value of the heat source and the preset first heat exchanger are determined. The amount of heat transferred to the hot water circulated through the first heat exchanger from the efficiency of the first heat exchanger, and the amount of the hot water determined from the transferred heat and the temperature rise rate of the remaining hot water in the bathtub. Measurement method. 3. When the heating medium is used for a purpose other than the heating of the hot water in parallel with the heating of the hot water, supply of the heating medium to the other uses is temporarily stopped, and The circulation flow rate is calculated in advance from the temperature of each hot water at the inlet where the hot water enters the heat exchanger and at the outlet where the hot water returns to the bathtub, and after the suspension is released, the calculated circulation flow rate is used to perform the transmission. 3. The remaining hot water measuring method according to claim 1, wherein the calorific value is obtained.