DE102022126351A1 - Heater with a heating block with different materials - Google Patents

Abstract

The invention relates to a heating device (1) for a building, with a heating block (2) and an electric heating device (3), wherein the heating block (2) is formed with a first material (4), wherein at least one channel (5) runs through the heating block (2), which defines a water path (6) through the heating block (2), wherein the water-conducting inner surface (7) of the channel (5) is formed at least in sections with the first material (4), wherein the electric heating device (2) has at least one electrically heatable element (8), wherein the electrically heatable element (8) is arranged in a heating section (9) of the channel (5) and wherein the water-conducting inner surface (7) of the channel (5) in the heating section (9) is formed with a second material (10) that is different from the first material (4), wherein a measure of the flammability of the second material (10) has a higher value than a corresponding measure of the flammability of the first material (4).

Description

The invention relates to a heating device for a building, with a heating block and an electric heating device. Corresponding heating devices can be used, for example, as an electric instantaneous water heater (VED heater), component of a heating system for providing hot water or the like.

Corresponding heating blocks for electrically heating water in a heating system or a continuous flow heater are usually made of or made of plastic. For example, electric heating cartridges are known as additional heaters in heating devices or electric continuous flow heaters for providing warm water for the shower and/or bathtub in the bathroom, or for the sink in the kitchen with such heating blocks.

In the known devices, the entire heating block is usually made of temperature-resistant or glow-wire-resistant plastic, since contact between the bare wire heating coils and the surface of the heating channel cannot be ruled out during operation. This means that higher-quality and usually more expensive plastic must usually be used for the entire heating block, although this is only necessary in the area of the heating coil, since this is the only place where contact can take place between the heating coil and the heating block. This results in higher costs for the production of the heating block.

It is therefore an object of the invention to at least partially solve the problems described with reference to the prior art. In particular, a heating block for a heating device is to be provided which is advantageously cheaper to manufacture.

These objects are achieved with a heating device for a building, with a heating block and an electric heating device, according to the features of independent claim 1. Advantageous embodiments are specified in the subclaims and explained in more detail in the following description.

To this end, a heating device for a building, with a heating block and an electric heating device, wherein the heating block is formed with a first material, wherein at least one channel runs through the heating block, which defines a water path through the heating block, wherein the water-conducting inner surface of the channel is formed at least in sections with the first material, wherein the electric heating device has at least one electrically heatable element, wherein the electrically heatable element is arranged in a heating section of the channel and wherein the water-conducting inner surface of the channel in the heating section is formed with a second material that is different from the first material, wherein a measure of the flammability of the second material has a higher value than a corresponding measure of the flammability of the first material.

The heating device is intended and set up for use in a building, for example. The heating device can be intended and set up for connection to a building and/or to supply lines, such as water pipes and/or power lines, for example. For example, the heating device can be connectable to a wall of a building, such as an interior wall of an apartment. The heating device can be used to heat a building or part thereof, such as a residential building or an apartment, and/or in particular to heat a water supply, such as a water circuit in the residential building. Such a heating device can be a gas heating device, such as a gas condensing boiler and/or a gas condensing boiler. In this context, the heating block can be part of an additional electric heater, for example. At least one electric heating cartridge can be arranged in the heating block, which can represent or comprise the electrically heatable element. The heating device can (alternatively and preferably) be used, for example, to heat water for use in an apartment in the building. In this context, the heating device can, for example, be an electric instantaneous water heater or a VED heater.

The heating block can be formed, for example, with a (particularly single) molded body. The at least one channel can be formed in the molded body. The channel can run through the molded body in a single or multiple winding in order to define the water path through the molded body. The molded body can be formed in one piece or in one piece. Alternatively, the molded body can be formed with several molded body parts, such as shells, which can be assembled to form the molded body. The shell construction is particularly advantageous in order to be able to form channels into which one or more inserts can be partially introduced. The heating block or molded body can, for example, be cast, printed, produced using an injection molding process or the like. The heating block or molded body can, for example, be formed to at least 80% or at least 90% with or from the first material.

The measure of flammability may, for example, be a glow wire ignition temperature (or glow wire flammability temperature) or a glow wire ignition index (or glow wire flammability index) or a Glow wire resistance. According to an advantageous example, the measure of flammability is the (respective) glow wire ignition temperature. Thus, for example, it can be provided that the second material has a higher glow wire ignition temperature than the first material. For example, the glow wire ignition temperature of the second material can be 650°C or more. The glow wire ignition temperature of the first material can be below 650°C. This advantageously ensures an ignition resistance relevant for approval procedures (e.g. IEC 60335-1) under the influence of a glowing wire of generally 650°C (glow wire ignition temperature (glow wire resistance)/glow wire ignition temperature according to IEC 60695-2-13) in the relevant area of the heating block (namely in the heating section), and at the same time the heating block can be manufactured more cheaply overall.

For example, a glow wire test can be carried out to measure the degree of flammability. The glow wire test can be used to advantageously simulate the overheating of wires or components such as resistors or capacitors. The household appliance standard IEC 60335-1, for example, requires glow wire testing for installed plastics and components in unattended devices such as washing machines, dishwashers, etc., as defects with serious consequences can occur here despite proper use. To carry out the glow wire test, the flame behavior of the material can be determined using a glowing wire that presses onto a test specimen made of a material to be tested, for example plastic. The result is then usually included as a characteristic value in the properties of the material (e.g. plastic). Such a value can advantageously represent a measure referred to here as a "measure of flammability".

Standardized test methods can be used to carry out the glow wire test. For example, there are two test methods for glow wire testing standardized in EN 60695-2 and IEC 60695-2-13: The first test method is used to determine a glow wire ignition index or glow wire flammability index (GWFI for short). The first test method therefore determines a so-called flammability number or flammability index. From this key figure, it can be deduced to what extent a flame extinguishes when the material is deprived of this ignition source after the glow wire is pressed against it and at the same time does not emit any fire-hazardous particles (e.g. drops). Example for a 2 mm thick sample at 775°C: GWIT: 775 / 2.0. The second test method is used to determine a glow wire ignition temperature (GWIT for short). This determines the ignition temperature of a material. It describes the highest temperature that does not cause ignition by the glowing wire during three consecutive tests. The temperature can be measured, for example, using a thermocouple that measures directly at the tip of the glow wire. Alternatively or cumulatively, a non-contact measurement can be carried out using an optical temperature sensor.

The heater may form an electric instantaneous water heater. The water path may extend from a cold water inlet to a hot water outlet of the heater. The water path may have one or more turns. The water path may have a meandering shape. One or more channels or water paths may extend through the heating block. One or more (possibly separate) heating sections may be formed in the heating block.

The first material can be a plastic material. The first material can be, for example, polypropylene. The first material can be, for example, a (glass fiber reinforced polypropylene.

The second material can be a plastic material, a ceramic material or a metallic material. For example, (glass) fiber reinforced polyamides, polyphthalamides or polyphenylene sulfides or oxide ceramics (silicon oxide, aluminum oxide) or light metals such as aluminum or stainless steels can be used as the second material.

The water-conducting inner surface of the channel can be formed in the heating section with at least one tubular insert part that is made of the second material. When inserted, the insert part can be surrounded by the first material on its outer surface. The tubular insert part can have a round, in particular circular, cross-section. A length of the insert part can, for example, define a length of the or a heating section or vice versa.

The water-conducting inner surface of the channel can be formed in the heating section with at least one line section formed with the second material. The line section can be inserted between two open ends of the channel. The line section can span an open area of the channel or bridge. The line section can be formed, for example, with a tube that is formed with or from the second material. The tube can be inserted into a free space in the heating block. A length of the line section can, for example, define a length of the or a heating section or vice versa.

The electrically heatable element can be a bare wire heating element. In particular, the water-conducting inner surface of the channel in the heating section can be formed by means of a glow wire-resistant insert for bare wire heating elements. One or more (possibly separate from each other) electrically heatable elements can be provided. The electrically heatable element can, for example, have the form of a heating coil. For example, the electrically heatable element can be a bare wire heating coil or comprise one.

The invention will now be explained in detail with reference to the figures.

• 1: beispielhaft und schematisch ein hier beschriebenes Heizgerät mit einem Heizblock in Schnittdarstellung.
• 2: eine beispielhafte Ausführungsform eines Heizblocks für ein hier beschriebenes Heizgerät in perspektivischer Ansicht.
• 3: eine weitere beispielhafte Ausführungsform eines Heizblocks für ein hier beschriebenes Heizgerät in perspektivischer, teilweise geschnittener Ansicht.

They represent:

• 1 : an example and schematic of a heating device described here with a heating block in a sectional view.
• 2 : an exemplary embodiment of a heating block for a heating device described here in perspective view.
• 3 : another exemplary embodiment of a heating block for a heating device described here in a perspective, partially sectioned view.

1 shows, by way of example and schematically, a heating device 1 for a building, with a heating block 2 and an electrical heating device 3, wherein the heating block 2 is formed with a first material 4, wherein at least one channel 5 runs through the heating block 2, which defines a water path 6 through the heating block 2, wherein the water-conducting inner surface 7 of the channel 5 is formed at least in sections with the first material 4, wherein the electrical heating device 3 has at least one electrically heatable element 8, wherein the electrically heatable element 8 is arranged in a heating section 9 of the channel 5 and wherein the water-conducting inner surface 7 of the channel 5 in the heating section 9 is formed with a second material 10 that is different from the first material 4, wherein a measure of the flammability of the second material 10 has a higher value than a corresponding measure of the flammability of the first material 4. As a measure of the flammability, the glow wire ignition temperature can be used, for example. (GWIT for short) according to IEC 60695-2-13.

The heating device 1 here forms, for example, an electric continuous flow heater. The water path 6 extends from a cold water inlet 11 to a hot water outlet 12 of the heating device 1. The electrically heatable element 8 can be, for example, a bare wire heating element.

The first material 4 here is, for example, a plastic material, for example a glass fiber reinforced polypropylene.

The second material 10 can be a plastic material, a ceramic material or a metallic material. Here, for example, the second material 10 can be a glass fiber reinforced polyphthalamide.

2 shows an exemplary embodiment of a heating block 2 for a heating device 1 described here. The heating block 2 is formed here by way of example with a first shell 18 and a second shell 19.

The water-conducting inner surface 7 of the channel 5 can be formed, for example, in the heating section 9 with at least one tubular insert 13 which is formed with the second material 10. In 2 In this context, for example, four insert parts 13 are shown. For example, a length of the insert part 13 can define a length of the heating section 9. If several insert parts 13 are present, they can each define a heating section 9 or together define a heating section 9. In the inserted state, the (respective) insert part 13 can be surrounded by the first material 4 on its outer surface 14. This is the case here, for example, when the two shells 18, 19 are connected to one another.

3 shows a further exemplary embodiment of a heating block 2 for a heating device 1 described here. 3 illustrates by way of example that several heating sections 9, in particular spaced apart from one another, can also be provided. The water-conducting inner surface 7 of the channel 5 is formed here by way of example in a heating section 9 with a tubular insert 13, which is formed with the second material 10. In addition, the water-conducting inner surface 7 of the channel 5 is formed here by way of example in a (further) heating section 9 with at least one line section 15, which is also formed with the second material 10. The line section 15 is inserted here by way of example between two open ends 16, 17 of the channel 5.

Advantageously, the heating block 2 can be made of simple, non-hot-wire-resistant (cheaper) plastic as the first material 4 and only the heating channels, ie the heating sections 9 of the channel 5, which contain the electrically heatable element(s) 8 (e.g. heating coil), receive one or more insert(s) 13 made of hot-wire-resistant material as the second material 10, which encloses the heating coil. The inserts (13) can consist of plastic or another hot-wire-resistant material as the second material 10. The heating block 2 can, for example, have a two-part structure (cf. 2 ) or a three-part structure (cf. 3 ). The insert parts 13 can, for example, be formed as a glow wire resistant insert for bare wire heating elements.

Because the water-conducting inner surface 7 of the channel 5 in the at least one heating section 9 is formed with a second material 10 that differs from the first material 4, wherein a measure of the flammability of the second material 10 has a higher value than a corresponding measure of the flammability of the first material 4, the heating block 2 can be made predominantly from a cheaper material. For example, a glow wire ignition temperature according to IEC 60695-2-13 of approximately 650°C can serve as a measure of the flammability of the second material 10.

Thus, a heating device 1 for a building, with a heating block 2 and an electric heating device 3, can be specified, which can at least partially solve the problems described with reference to the prior art. In particular, a heating block 2 for a heating device 1 can be provided, which is advantageously cheaper to manufacture.

List of reference symbols

1

heater

2

Heating block

3

Heating device

4

first material

5

channel

6

Waterway

7

Inner surface

8th

heatable element

9

Heating section

10

second material

11

Cold water inlet

12

Hot water outlet

13

Insert

14

Outer surface

15

Line section

16

open end

17

open end

18

first bowl

19

second bowl

Claims (10)

Heating device (1) for a building, with a heating block (2) and an electrical heating device (3), wherein the heating block (2) is formed with a first material (4), wherein at least one channel (5) runs through the heating block (2), which defines a water path (6) through the heating block (2), wherein the water-conducting inner surface (7) of the channel (5) is formed at least in sections with the first material (4), wherein the electrical heating device (2) has at least one electrically heatable element (8), wherein the electrically heatable element (8) is arranged in a heating section (9) of the channel (5) and wherein the water-conducting inner surface (7) of the channel (5) in the heating section (9) is formed with a second material (10) that is different from the first material (4), wherein a measure of the flammability of the second material (10) has a higher value than a corresponding measure of the flammability of the first material (4). Heater (1) after Claim 1 , wherein the heating device (1) forms an electric instantaneous water heater. Heater (1) after Claim 1 or 2 , wherein the water path (6) extends from a cold water inlet (11) to a hot water outlet (12) of the heater (1). Heater (1) according to one of the preceding claims, wherein the first material (4) is a plastic material. Heating device (1) according to one of the preceding claims, wherein the second material (10) is a plastic material, a ceramic material or a metallic material. Heating device (1) according to one of the preceding claims, wherein the water-conducting inner surface (7) of the channel (5) in the heating section (9) is formed with at least one tubular insert (13) which is formed with the second material (10). Heater (1) after Claim 6 , wherein the insert part (13) in the inserted state at its Outer surface (14) is surrounded by the first material (4). Heating device (1) according to one of the preceding claims, wherein the water-conducting inner surface (7) of the channel (5) in the heating section (9) is formed with at least one line section (15) which is formed with the second material (10). Heater (1) after Claim 8 , wherein the line section (15) is inserted between two open ends (16, 17) of the channel (5). Heating device (1) according to one of the preceding claims, wherein the electrically heatable element (8) is a bare wire heating element.

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