DE8816946U1 - Heating arrangement with at least one heat generator and parallel-connected storage tanks for heating water and hot water - Google Patents

Description

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Heating arrangement with at least one heat generator and parallel-connected storage tanks for heating water and hot water

The subject of the present innovation is a heating arrangement with at least one heat generator, which is connected to a buffer storage tank to reduce the burner cycles, whereby the buffer storage tank is connected on the one hand between the flow and return of the heat generator and on the other hand between the flow and return of the heating circuit in the manner of a heating water buffer.

A heating arrangement mentioned at the beginning with at least one heat generator which is combined with a buffer storage in order to reduce the burner operating times is already known from EP 0 122 475 A1.

It has already been recognized there that in order to reduce the number of burner starts, it is necessary to connect a heat generator (e.g. an oil or gas boiler) with a relatively low water content to a buffer storage tank with a larger water content in such a way that the buffer storage tank is arranged between the heat generator and the heating circuit.

This has the advantage that over the operating period only relatively few burner starts are required, each of which results in high soot emissions and the emission of other poisonous gases.

The disadvantage of the known heating system is that the buffer tank is only connected in the bypass to the heat generator and not directly between the heat generator and the heating circuit. This results in a relatively complicated piping system.

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ψ-t ψr ·

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with a high level of control effort to control the bypass flow depending on the different operating states of the system.

Furthermore, the heating system mentioned cannot ensure that the boiler is always kept free of the cold heating water flowing back from the heating system's return line. This has the disadvantage that deposits in the boiler increase and condensation on the heat exchanger surfaces cannot be prevented.

From DE-Z: Wärmetechnik 8/1987, pages 331 to 334, it is also already known to connect a buffer storage tank in parallel to a heat generator. However, the known heating arrangement draws the heating water for operating the heating system and the hot water for domestic water production from one and the same buffer storage tank, so that disadvantages can arise here if there is a strong drop in temperature in the heating or domestic water area, which both originate from one storage tank.

The aim of the innovation is to further develop a heating arrangement of the type mentioned at the outset in such a way that, while improving efficiency, longer burner running times and a further reduction in the pollutant emissions of the heat generator are ensured.

The solution to the problem is achieved by the technical teaching set out in claim 1, which essentially consists in the fact that in addition to the buffer storage for heating water, a further storage tank for domestic water or for hot water is connected in parallel to the heat generator, so that a uniform combination storage tank is present in the form of the heating water buffer and the hot water storage tank.

This has the advantage that in all operating states the heat generator is always flowed through by preheated water from the buffer tank and that ^a buffer is also formed with regard to the domestic water or hot water. This ensures that the colder water flowing back from the heating circuit only reaches the buffer tank and not the hot water tank or that the buffer tank is not filled with water, as this refers to the domestic water tank and not to the heat generator, which is protected from direct fluctuations in heat.

This results in considerably longer burner times of e.g. 1 hour and longer, whereby this time is essentially due to the new control system and the difference in the volume of the buffer tank or hot water tank compared to the volume of the heat generator.

Another essential feature of the present innovation and the hot water storage tank is the connection of the heat generator with the aforementioned buffer storage tank with a heat pump circuit, which in turn contains a pn wpitprpn buffer storage tank.

The combination of this heat pump circuit with the buffer storage tank assigned to it in conjunction with the buffer storage tank of an oil or gas boiler or the parallel hot water tank for domestic water results in further significant advantages.

This proposes a standardized heating arrangement, the most important components of which are prefabricated as modules, which ensure that a partial expansion, later retrofitting or pipework adjustment can be carried out at any time.

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The main advantages of such a modular system are
follows:

1. Significantly longer running time of the oil burner or heat pump.
Reduction of pollutant emissions and less wear of the
Devices.

2. This mode of operation is also beneficial for the chimney, as it reduces condensation problems

3. There are fewer residues from combustion in the boiler, as it
runs for a longer period of time at a higher temperature. This
Operating mode also has a positive effect on the service life of the boiler
out of.

4. Over a relatively long period of time (transition period and external heat influence)
With a two-pipe heating system there is the situation that only a small amount of heat (amount of water) is taken and therefore also a
This also has a negative effect on the boiler. Just as problematic for the boiler is
a low-temperature system or underfloor heating. With this solution, the relatively cold return water goes into the
buffer tank and not directly into the boiler.
Boiler heating, the return flow is very quickly at normal
Temperature. (Temperature mixing in the storage tank).
The extraction of domestic water does not have a direct impact on the heat generator.

The subject matter of the present invention arises not only from the subject matter of the individual claims, but also from the
Combination of the individual protection claims with each other.

AlI*. information and features disclosed in the documents - including the summary, in particular those in the drawings

\.[. The spatial configuration shown is considered essential to the invention

if claimed.

In the following, the innovation is explained in more detail using drawings that merely show an embodiment. The drawings and their descriptions reveal further key features and advantages of the innovation.

Figure 1: schematically shows a heating arrangement according to the innovation;

'■', Figure 2: Top view of the components of the heating arrangement according to Figure

y. A heat generator 2, which is designed as an oil or gas boiler,

^; works with its flow line 18 on a three-way valve S2, into which

; ^: at the same time the flow line 20 of a heat pump 1 flows into it.

|: The output of the three-way valve S?. is formed by a line 22,

&rgr; in which a pump Pl is switched on, which is connected via a line 23 to a

~"- second three-way valve S3 is working.

A line 11 branches off from the three-way valve S3 as a supply line for a ·"■ buffer tank 8 and a line 16 as a supply line for a

&Idigr;, heat exchanger 15 of a domestic hot water storage tank 3.

In the buffer tank 8, on the flow side, there is a - only schematically

Si shown - chicane 9 is arranged, which ensures that the

]■■ Buffer tank 8 warmer water is distributed evenly in the

'■=. Buffer memory 8 distributed.

¹¹¹ -ItN

The line 12 of the buffer tank 8, which forms the return flow, opens into an immersion pipe 10 in the bottom area of the buffer tank 8, so that it is ensured that only the colder ^water collecting in the bottom area leaves the buffer tank 8 via the line 12.

The output of the buffer memory 8 is formed by a line 13,

which opens onto a three-way valve 31, which also has a

Bypass line 30 and the one forming the flow for the heating circuit'.; Attach line 31.

The return of the heating system is formed by the line 32, from which the flow line 30 branches off and which then passes into a line 14 which leads the colder water returning from the heating circuit into the bottom area of the buffer tank 8.

A domestic hot water storage tank 3 is connected in parallel to the buffer tank 8. The heat exchanger 15 is supplied on the inlet side via line 16 by the three-way valve S3 and the outlet side flows into the return line 19 of the heat generator 2 via line 17.

A heat pump system is connected in parallel to the previously described heat generator 2 with the buffer storage tank 8 and the heat exchanger 15 of the domestic hot water storage tank 3, which in turn has a buffer storage tank 4.

The flow line 20 of the heat pump 1 flows into the three-way valve S2. The return line 21 of the heat pump 1 is connected to the return line 19 of the heat generator 2.

The absorber circuit of heat pump 1 is made up of the following parts :

In the return line of the heat pump 1, a line 24 is arranged which leads to a pump P4, which pumps the brine into the bottom area of an absorber 7.

The brine is heated by solar radiation and leaves the absorber on the upper side via a line 25, which leads into a three-way valve S4. The outlet of the three-way valve S4 is formed by a line 26, in which a pump P3 is switched on, which flows into the heat pump 1 via a line 27.

Parallel to the return of the heat pump 1, namely to the line 24, there is a line 29 which forms the cooling water line of the heat exchanger 4a arranged in the buffer tank 4.

The outlet side of the heat exchanger 4a is formed by the line 28, which opens into the three-way valve S4.

The arrangement of the heat exchanger 4a in the buffer tank 4 ensures that the warmer water rises in the direction of arrow 33 to the ceiling of the buffer tank 4, while the colder water falls down the side walls of the buffer tank 4 in the direction of arrow 34 towards the floor.

A sensor F5a is arranged in the gap area of the buffer tank 4 and a further sensor F5b is arranged in the floor area.

A sensor F4 is arranged on the outlet side of the absorber 7.

A sensor F6 is located in the heater 2.

In the return line of the buffer tank 8, namely in the area of the line 12 and

&igr; · · a · · _{aa a}

the line 17, a sensor Fl is arranged.

A sensor F2 is arranged in the flow of the heating system, namely in the area of line 31.

A sensor F3 is located in the lower part of the domestic hot water tank 3.

A sensor F7 is arranged in front of the return line 19 of the heat generator 2 and behind the lines 12,17 of the buffer tank 2 or the domestic hot water tank 3.

A minimum thermostat Dl is arranged in the corner area of buffer tank 4.

The system is now operated as follows: The control device 5 fulfils the following functions: Outside temperature dependent release of the Iten heat generator heat pump 1.

Bivalence point for enabling the 2nd heat generator with restriction of the minimum thermostat Tl, i.e. the oil burner is already enabled by the outside temperature, but is only switched on when the cold buffer tank 4 is empty. (^>0°C).

Separate heating curve adjustable for the mixer Sl. The heating circulation pump PZ is controlled according to demand. _f , The domestic water priority circuit causes the heat pump or the boiler to

« the upper temperature level is reached and the mixer Sl closes and the pump P2 switches off. A run-on time of 3 minutes ensures that the heat in the heat pump or boiler is still transported away after the required temperature has been reached at the sensor F3.

Additional functions of the control in the control cabinet in connection with the control 5.

The heat pump or burner is only released when the mixer motor Sl is fully open. This is achieved by an adjustable signal contact and a time delay.

The heat pump or burner only switches off again when the required value is reached at the Fl sensor in the return. This means that the heating water buffer is completely flushed and charged.

The residual heat now present in the boiler is gradually fed to the heating water buffer using a differential temperature control system. For this purpose, the sensor F6 is installed in the boiler and the sensor F7 is installed in the return line from the buffer.

In order to bring the boiler up to temperature relatively quickly, the pump Pl is switched on with a delay after the burner starts.

The valve S3 is open to the heating water buffer when there is no current and when the hot water is to be heated, the valve switches to the heat exchanger in the hot water storage tank.

Charging pump Pl buffer tank 8:

The pump Pl must run when the oil boiler or heat pump is in operation with the following additional functions during heating operation (and hot water preparation). Start-up delay: (only heating boiler operation)

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In order to bring the boiler up to temperature relatively quickly, the pump is switched on with a delay via a time relay (adjustable 5 - 10 min.)

(Same function for hot water heating)

If the required temperature is reached at sensor Fl (sensor 3 for hot water preparation), the burner or the heat pump and the charging pump switch off. (For hot water preparation, valve S3 and the charging pump are still supplied with power for 3 minutes, i.e. part of the boiler heat is still discharged into the storage tank.)

In order to make effective use of the residual heat in the boiler, this heat is gradually fed into the heating buffer via a simple Δt control.

The charging pump Pl is put into operation using two temperature sensors (F6 boiler and F7 return from buffer and heat exchanger) and a set Δt of approx. 8 K.

If the boiler has been started up to prepare hot water, the heat in the boiler is also fed to the heating buffer via this circuit.

Burner or heat pump activation or release during heating operation ].) Via the boiler sensor Fl (with the restriction see 2)

2.) The additional signal contact in the mixer motor Sl releases the boiler or heat pump again after a time delay. At approx. 80 - 90% of the mixer opening, this contact activates a time relay, which then starts the burner or heat pump after 40 minutes.

¹¹¹ - Ib. ...

The following advantages are achieved by this circuit:

a. The storage volume is fully utilized.

b. This results in very long burner running times or down times without the boiler cooling down, since the heat is fed into the heating system.

c. The cycling of the oil burner with the respective pollutant emissions during start-up is greatly reduced.

In the following, the functions ¹ IeS absorber circuit si on s in connection with the heat pump 1 are described in more detail:

Pressureless Kait buffer tank 4 with specially arranged heat exchanger made of Cu finned tubes, capacity approx. 1,200 L.

The latent storage tank is filled with normal water with the addition of a corrosion inhibitor. A brine mixture with approx. 30% Antifrogen N content flows through the heat exchanger.

The sensor arrangement as well as the electronic control and the special integration of the heat exchanger 4a ensure optimum operation during charging and also during removal.

Charging process:

The differential temperature control device 6 and the two sensors F4 and F5b determine whether the temperature level at F4 is higher than that at F5t . If this is the case, the brine pump P4 starts operating and the distribution valve S4 opens the path AB. The buffer storage is now charged as long as the temperature at F4 is higher than that at F5b.

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The arrangement of the heat exchanger ensures that the upper warmer
Layer in the storage tank is partially transported downwards. This
Buffer is heated completely and the maximum amount of energy is stored.
Max. limitation of the storage tank temperature is present. (Protection of the HP '■' against overtemperature). With an adjustable difference of approx. 3 K
then switches the brine pump P4 off again. |

Unloading process:

The request for the Wf is first determined by the control unit 6 with the sensors

F4 and F5a are checked to see where the higher temperature level is. If this

If this is the case with F5a, the distribution valve S4 opens the path B-AB and

the pump P3 is running. Now the heat is transferred via the heat exchanger la until

withdrawn from the buffer above until the temperature at F5a is equal to F4 ■'.'

and then the heat is fed back to the heat pump via the absorber. :'■

The buffer tank is equipped with a heat exchanger 4a, as well as

with a water level indicator, temperature sensors and a

Minimal thermostat Tl. Sound-insulating elements :; are used as a base, as well as a condensate collecting tray.

DaSj/&khgr; t is constantly recorded (when the heat pump is running and when it is not running) | with the control device 6.

For heat pump operation, the higher temperature level is always used, i.e.

either absorber 7 or cold buffer tank 4. If WP 1 is required by sensor t Fl, the upper sensor on the cold buffer tank side is

F5a switched! ^

If HP 1 is switched off, the value between F4 and F5b is compared and pump P4 is put into operation. (If F4 is like F5b).

• · t ta

• til ■ &lgr; -

• · t tit • * * ' i III ■

Three-way mixer S4

:·; Operating mode 1 charging K-buffer

■ = Standstill of the WP At between F4 and F5b is

;i moved and P4 put into operation when heat is available.

^! ; Temperature at sensor F4 ^> as at F5b

pi mixer has opened the path A - B (line 25,28)

p rUmpG rf &idigr; &Pgr;&udigr;&thgr;&igr;&Pgr;&kgr;&ugr;

In this circuit, the absorber heat is fed to the cold buffer tank. In addition, the warmer layer in the upper part of the

if cold buffer tank 4 with the special arrangement of the heat exchanger 4a

[■ wc+i "tvacti urrten rartiert and thus an optimal charging

&igr;, of the cold buffer storage is reached.

I Operating mode 2 HP operation with absorber

During WP operation, the Zi t is compared between -4 and F5a.

&egr; Temperature at F4 ^ as F5a = absorber operation

I Pump P3 in operation

& Pumnp &Rgr;&Lgr; in Rotrioh

w. "" ^r ~ —'"

Mixer has opened path A-AB (line 25,26) Operating mode 3 HP operation with cold buffer tank

Temperature at F5a ^> like F4 = cold buffer operation Mixer has opened path B-AB (line 28,26)

Brine pump P3

Pump starts operating with the heat pump

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(Operating time identical to WP)
Brine pump P 4

Pump starts operation via &Dgr; t Regf ^1r device ( whenever sensor F4 has a higher temperature level than sensor F5n in heat pump operation or in the rest position as in 5b).

Thermostat Tl switches off the heat pump and enables the oil burner. Depending on the heat requirement of the house, the setting is approx. 0° or higher. The heat pump is now blocked for an adjustable time U^, 1 .&Oacgr; .StcL - - .','-.OSLd*) ! Reasons - Prevent the heat pump from cycling and achieve a reasonable running time and temperatures for the boiler and chimney.

If heat is requested again after this time and the heat pump is released with the bivalence point set on the TEM control, then it only goes into operation via the switch if the temperature at F4 is temporarily higher than at F5a.

With the system described, burner running times of 1 3/4 hours could be achieved, whereby a 3-fan house with a burner output of 21 kW was to be supplied with heat and domestic water at an outside temperature of 0 ⁰ C to +5 ^C.

The buffer storage 8 was discharged once over a period of 1 1/2 hours, only then did the burner switch on again for a period of approx. 1 hour.

This was based on a boiler capacity of 30 to 40 litres compared to a buffer storage capacity of 120 litres.

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This ensures optimal operating conditions because the boiler is always operated at 30 to 60 ^° C, i.e. in the gentle operating range, and the downtime and radiation losses are minimal due to the small boiler capacity.

DRAWING LEGEND

1 heat pump Sl three-way valve Pl pump 2 heat generators S2 three-way valve P2 pump 3 domestic hot water tanks S3 three-way valve P3 pump 4 buffer storage S4 three-way valve P4 pump 4a Heat exchanger 5 Control device 6 Control device Fl sensor Tl Minim 7 absorbers F2 sensor 8 buffer storage F3 sensor ■9 "Sttrifc^ne F4 Sensor 10 Dip tube F5a sensor F5b sensor 11 Management F6 Sensor 12 Line F7 Sensor 13 Management 14 Management 27 Management 15 heat exchangers 28 Management 16 Line 29 Management 17 Management 30 Bypass line 18 Flow (boiler Z) 31 Line 19 Return (boiler 2) 32 Line 20 Flow (heat pump) 33 Arrow direction 21 Return (heat pump) 34 Arrow direction 22 Line 23 Management 24 Line 25 Line 26 Line

Claims (12)

ir-eN.icm.chtvom Date vcu'.e::eror Dale 28 December 1990 Applicant: Mr. Josef Moosmann, Affentäle 2a, 774J Tennenbronn Protection claims 1. Heating arrangement with at least one heat generator which is connected to a buffer storage tank in order to reduce the burner cycles , the buffer storage tank being connected on the one hand between the flow and return of the heat generator and on the other hand between the flow and return of the heating circuit in the manner of a heating water buffer, characterized in that a heat exchanger (15) is connected in parallel to the buffer storage tank (8) in the additional hot water storage tank (3), whereby a uniform combination storage tank is created. Telephone. Telex: Facsimile / Fax: «Lindau 10 83 82) 5 43 74 (patent -d) »49-8382-7(10 27 7 80 25 Telegram - Address petri-lindau Bank accounts. Postal checking account Bayer Vereinsbank Lindau(B) No. 1257 110(bank code 735 200 74) Münctien414e48-808 Hypo-Bank Lindau (Bl No. 66 70-328813 (BLZ 733 204 42) _V 3LZ 70010080) Volksbank L.naau (B) No. 51 222 000 (BLZ 735 901 20) -Z- 2. Heating arrangement according to claim 1, characterized characterized in that, in order to charge the domestic water storage tank (3), a three-way valve (S3) is arranged in the flow line (line 11) of the buffer storage tank (8) and the heat generator (2), one line (16) of which forms the flow line of the heat exchanger (15) of the domestic water storage tank (3). 3. Heating arrangement according to claim 1, characterized characterized in that a heat pump arrangement consisting of absorber (7), buffer storage (4) and heat pump (1) is connected in parallel to the heat generator (2). 4. Heating arrangement according to claim 1, characterized in that the combination storage tank, consisting of buffer storage tank (8) and domestic water storage tank (3), is arranged parallel to the heat generator (2) on the one hand, and that the heat pump arrangement, consisting of absorber (7), buffer storage tank (4) and heat pump (1) is connected in parallel to the heat generator (2) on the other hand. 5. Heating arrangement according to claim 4, characterized in that a service water priority circuit causes the heat pump (1) or the heat generator (2) to be driven to the maximum achievable temperature level, and that the three-way valve (S1) arranged in the heating circuit (31, 32) closes and switches off the pump (P2) arranged there, whereby the heat is transported away from the heat generator (2) or the heat pump (1) with a run-on period of, for example, 3 minutes after the service water temperature determined by a sensor (F3) has been reached. 6. Heating arrangement according to claims 1 to 5, characterized in that the heat pump (1) or the -3- The heat generator (Z) may only be started when the three-way valve (Sl) in the heating circuit (31,32) is fully open. 7. Heating arrangement according to claim 4, characterized in that the heat pump (1) or the heat generator (?) only switch off when a predetermined value is reached by a sensor (Fl) return flow (19,?1;) and that the residual heat then present in the heat generator (2) is gradually fed to the buffer storage tank (8) by means of a differential temperature control system (Cj). H. Heating arrangement according to claim 7, characterized in that the ^differential temperature control (5) consists of a sensor (F6) arranged in the heat generator (2) and a sensor (F7) arranged in the return line (line 12) from the buffer storage tank (8). 9. Heating arrangement according to claims 1 and 2, characterized in that for accelerated heating of the starting heat generator (2) the pump (P1) arranged in the heating circuit [2?, 23) switches on with a delay. 10. Heating arrangement according to claims 1 to 4, characterized in that a three-way valve (S2) is provided for switching the flow (line 20) of the heat pump (1) and the flow (line 18) of the heat generator (2) to the buffer tank (8). 11. Heating arrangement according to claims 1 to 4, characterized in that for operating the heat pump (1) a differential temperature control device (6) with two sensors (F4, F5a) on the input side is provided, whereby one sensor (F4) is located in the return line (line; 25) of the absorber (7) and the other sensor (F5a) in the upper area „4- of a further buffer storage tank (4) is arranged, that at a higher temperature level at the puck run (line 25) of the absorber (7) compared to the bottom-side temperature of the buffer storage tank (4) the pump H'4) for the brine circuit of the absorber (7) is switched on and H,iij furthermore in the branching point between the return (line 25) of the absorber (7), the flow (line 27) of the heat pump (1) and the return (line 28) of the buffer storage tank (4/) a three-way valve (54) is arranged, which opens the return (line 27) to the heat pump (1) for this operating case. 12. Heating arrangement according to claim 11, characterized in that, in order to discharge the further buffer storage tank (4), it is first provided that the temperature level in the upper region of the buffer storage tank (4) is set higher than that on the return side of the absorber (7), and that the three-way valve (S4) to the flow line (line 27) of the heat pump then opens until the temperature in the upper region of the buffer storage tank (4) is approximately equal to the temperature in the return line (line 25) of the absorber (7).