EP0708299B1 - Safety method for water heaters and atmospheric gas burners during the return of combustion gases - Google Patents

Safety method for water heaters and atmospheric gas burners during the return of combustion gases Download PDF

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Publication number
EP0708299B1
EP0708299B1 EP95402311A EP95402311A EP0708299B1 EP 0708299 B1 EP0708299 B1 EP 0708299B1 EP 95402311 A EP95402311 A EP 95402311A EP 95402311 A EP95402311 A EP 95402311A EP 0708299 B1 EP0708299 B1 EP 0708299B1
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EP
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Prior art keywords
temperature
sensor
threshold
burner
return
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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EP95402311A
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German (de)
French (fr)
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EP0708299A1 (en
Inventor
Mohamed Benabdelkarim
Régis Cazin
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Saunier Duval Eau Chaude Chauffage SDECC SA
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Saunier Duval Eau Chaude Chauffage SDECC SA
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/20—Arrangement or mounting of control or safety devices
    • F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
    • F24H9/2035—Arrangement or mounting of control or safety devices for water heaters using fluid fuel
    • F24H9/2042—Preventing or detecting the return of combustion gases
    • F24H9/205—Closing the energy supply
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/24—Preventing development of abnormal or undesired conditions, i.e. safety arrangements
    • F23N5/242—Preventing development of abnormal or undesired conditions, i.e. safety arrangements using electronic means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/20—Control of fluid heaters characterised by control inputs
    • F24H15/235—Temperature of exhaust gases
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/355—Control of heat-generating means in heaters
    • F24H15/36—Control of heat-generating means in heaters of burners

Definitions

  • the invention relates to bath heaters and atmospheric gas boilers and more specifically a method for securing the device during discharge of combustion products, for example during blockage of the smoke exhaust duct.
  • the fixed trigger value of the heat-sensitive element is a disadvantage, because the lower temperature of the products combustion, when the burner operates at low flow, will not quickly reach this value, and will delay the lockout of the device.
  • this device with a sensor of temperature presents untimely disjunctions because the sensor reaches normal operation at large power, a temperature equivalent to that corresponding abnormal operation at low power.
  • Another solution is to use two temperature sensors, one placed in the normal flow of the other placed in the discharge flow of these fumes, see for example DE-A-3 020 228.
  • the thermal draft When the thermal draft is insufficient, the smoke is forced back into the living room by the appliance draft hood.
  • the two sensors temperature are therefore in the same flow of fumes driven back and consequently, the temperature differential between both fall rapidly to a few degrees. This variation of the temperature differential is used to secure the device.
  • the temperature of the sensor placed in the discharge flow will only decrease much more slowly since it continues to be subjected to the radiation of draft hood. Therefore the differential of temperature drops as quickly as if there are a repression.
  • the device must is equipped with intelligent electronics that take into account account for the fact that it is in the regulatory phase and which inhibits security during this phase so as not to be tripped.
  • a microprocessor system having in memory the set point indications of the sensors, could bring the device to safety according to the signals received from the sensors during a backflow but also based on signals from the burner reflecting the heating power at the instant considered.
  • the subject of the invention is therefore a method of placing in safety of atmospheric bath heaters and boilers gas during the discharge of combustion products, putting using a single temperature sensor placed in the flow delivery of said combustion products, process which consists in interpreting both the measures of variation of sensor temperature versus time and measurement temperature of the combustion products upsets associated with information on the burner load so that safety is only applied if the measurement of the temperature is above a determined threshold corresponding to the power.
  • FIG. 1 Partly shown in FIG. 1 is a boiler equipped with a burner 1, a heating body 2 to hot skirt surmounted by a draft hood 3 and a smoke evacuation duct 4.
  • the draft hood in known manner has side air inlets 5 and deflectors 6 above these air inlets.
  • a temperature sensor 7 in upper part of a deflector 6, that is to say in an area air inlet in normal operation, materialized by arrows 8. Combustion or smoke products escape from the heating body 2 to the duct 4, as shown by arrows 9.
  • the temperature T will grow quickly and then stabilize at a maximum value.
  • the method consists in associating with this measurement of the temperature T of the fumes by the sensor, information on the power under load of the burner.
  • the device will be locked out only if the temperature sensor has detected a rapid change in temperature and if the measurement of this temperature is above a threshold T 1 corresponding to low power operation of the device, or at a threshold T 2 for high power operation, or an intermediate threshold for an intermediate power.
  • the threshold between T 1 and T 2 is a linear function of the burner load and therefore of the power of the appliance. It adjusts automatically according to the instantaneous power of the device.
  • the diagram in FIG. 4 shows that a safety instruction collected at the ET output is subject to the temperature variation dT / dt, which in the case of operation at low power could be greater than or equal to 0.5 ° per second, as well as the determination of the temperature T which must be greater than or equal to the temperature T 1 . In the case of high power operation the only difference is that the temperature T must be greater than or equal to the temperature T 2 .
  • 10 is a derivation and 11 a hysteresis comparator.
  • the reference 12 illustrates the comparison of a temperature with the threshold cutoff T.
  • reference 13 represents ignition authorization followed by locking 14 towards authorization to request ignition 15.
  • the temperature has generally not yet reached the cutoff threshold T.
  • the dT / dt variation or slope is no more than about 0.1 ° per second. So you have to memorize the fact that at one point there was a rapid change in the temperature.
  • This solution has the enormous advantage of being easily and instantly verifiable from the point of view electronic, each time the burner is ignited.
  • the new process appears tolerant for chimneys with poor cold draft. Indeed a rapid variation of the temperature dT / dt is required for prevent the appliance from working.
  • the dT / dt threshold is adjusted so as to allow time for thermal draft of settle down.

Abstract

The system provides the boiler with a burner (1) and a heated body (2). Above this is a canopy (3) leading into a conduit (4) for removal of fumes with deflectors (5) guiding the gas flow. A single temp. sensor (7) is placed in the flow of exhaust prods. to measure both the absolute temp. (T) and the variation of temp. w.r.t. time (dT/dt). The sensor is able to measure temp. variations of the order of 0.1 to 0.5 deg. per second. This is then used in conjunction with measurement of the current flowing through a control electrovalve in order to provide control of the power provided by the boiler.

Description

L'invention se rapporte aux chauffe-bains et chaudières atmosphériques à gaz et concerne plus précisément un procédé pour la mise en sécurité de l'appareil lors du refoulement des produits de combustion, par exemple lors d'un bouchage du conduit d'évacuation des fumées.The invention relates to bath heaters and atmospheric gas boilers and more specifically a method for securing the device during discharge of combustion products, for example during blockage of the smoke exhaust duct.

Il est bien connu d'utiliser des dispositifs de sécurité assurant cette fonction, notamment dans les installations à ventilation mécanique contrôlée en vue de pallier à leur défaillance éventuelle. Une anomalie au niveau de l'extracteur, ou encore un bouchage des conduits se traduit par une élévation anormale de température au niveau du coupe-tirage. Habituellement on prévoit à ce niveau un thermostat ou un capteur de température qui, à une température prédéterminée, agit aussitôt dans le sens de l'arrêt du brûleur. Cette température à laquelle l'élément thermosensible provoque l'arrêt du gaz au brûleur est réglée entre la valeur de température admise lorsque l'appareil fonctionne dans des conditions normales de tirage et une valeur de température pour laquelle il y aurait un refoulement dangereux des produits de combustion. Cette valeur prédéterminée de température, dans le cas des appareils à puissance fixe, permet un arrêt pratiquement immédiat de l'appareil dès l'apparition d'une anomalie.It is well known to use security ensuring this function, especially in controlled mechanical ventilation systems for compensate for their possible failure. An anomaly at level of the extractor, or a blockage of the conduits results in an abnormal rise in temperature at level of the draft hood. Usually this is expected level a thermostat or a temperature sensor which, at a predetermined temperature, acts immediately in the direction of burner shutdown. This temperature at which the element thermosensitive causes the gas to stop at the burner is set between the permitted temperature value when the device operates under normal draft conditions and a temperature value for which there would be a dangerous discharge of combustion products. This predetermined temperature value, in the case of fixed power devices, practically shutdown immediately after the appearance of an anomaly.

Par contre, dans les appareils à puissance variable, dans lesquels le brûleur peut fonctionner à débit réduit, à débit maximum ou à des débits intermédiaires, la valeur fixe de déclenchement de l'élément thermosensible est un inconvénient, car la température plus basse des produits de combustion, quand le brûleur fonctionne à faible débit, ne permettra pas d'atteindre rapidement cette valeur, et retardera d'autant la mise en sécurité de l'appareil.On the other hand, in power devices variable, in which the burner can operate at a rate reduced, at maximum flow or at intermediate flows, the fixed trigger value of the heat-sensitive element is a disadvantage, because the lower temperature of the products combustion, when the burner operates at low flow, will not quickly reach this value, and will delay the lockout of the device.

De même, par exemple en été, avec des températures ambiantes de l'ordre de 30°C, ce dispositif avec un capteur de température présente des disjonctions intempestives car le capteur atteint en fonctionnement normal à grande puissance, une température équivalente à celle correspondant à un fonctionnement anormal à petite puissance. Similarly, for example in summer, with temperatures ambient around 30 ° C, this device with a sensor of temperature presents untimely disjunctions because the sensor reaches normal operation at large power, a temperature equivalent to that corresponding abnormal operation at low power.

Une autre solution consiste à utiliser deux capteurs de température, l'un placé dans le flux normal des fumées, l'autre placé dans le flux de refoulement de ces fumées, voir, par exemple DE-A-3 020 228.Another solution is to use two temperature sensors, one placed in the normal flow of the other placed in the discharge flow of these fumes, see for example DE-A-3 020 228.

Lorsque le tirage thermique est insuffisant, les fumées sont refoulées dans le local d'habitation par le boítier du coupe-tirage de l'appareil. Les deux capteurs de température se trouvent donc dans le même flux des fumées refoulées et par suite, le différentiel de température entre les deux, chute rapidement à quelques degrés. Cette variation du différentiel de température est exploitée pour mettre en sécurité l'appareil.When the thermal draft is insufficient, the smoke is forced back into the living room by the appliance draft hood. The two sensors temperature are therefore in the same flow of fumes driven back and consequently, the temperature differential between both fall rapidly to a few degrees. This variation of the temperature differential is used to secure the device.

Toutefois ce système à deux capteurs présente des inconvénients quand l'appareil est en phase de régulation. En effet lorsque la régulation déclenche l'arrêt du brûleur, la température du capteur situé dans le flux normal des fumées va chuter rapidement puisqu'il n'y a plus dégagement de fumées.However, this two-sensor system has disadvantages when the device is in the regulation phase. When the regulation triggers the burner to stop, the temperature of the sensor located in the normal flow of smoke will drop quickly since there is no more release smoke.

Par contre la température du capteur placé dans le flux de refoulement, ne va décroítre que beaucoup plus lentement puisqu'il continue à être soumis au rayonnement du boítier du coupe-tirage. Par conséquent le différentiel de température chute aussi rapidement que dans le cas où il y a un refoulement. Pour pallier à cela, il faut que l'appareil soit équipé d'une électronique intelligente qui prenne en compte le fait qu'il est en phase de régulation et qui inhibe la sécurité durant cette phase pour ne pas être disjoncté. Ainsi un système à microprocesseur ayant en mémoire les indications de consigne des capteurs, pourrait provoquer la mise en sécurité de l'appareil en fonction des signaux reçus des capteurs lors d'un refoulement mais aussi en fonction de signaux provenant du brûleur reflétant la puissance de chauffe à l'instant considéré.However, the temperature of the sensor placed in the discharge flow, will only decrease much more slowly since it continues to be subjected to the radiation of draft hood. Therefore the differential of temperature drops as quickly as if there are a repression. To overcome this, the device must is equipped with intelligent electronics that take into account account for the fact that it is in the regulatory phase and which inhibits security during this phase so as not to be tripped. Thus a microprocessor system having in memory the set point indications of the sensors, could bring the device to safety according to the signals received from the sensors during a backflow but also based on signals from the burner reflecting the heating power at the instant considered.

Mais, pour des raisons évidentes de coût, on ne peut envisager de monter un tel système sur des appareils de régulation classique, à seule fin d'assurer cette fonction de sécurité. But, for obvious cost reasons, we do not may consider mounting such a system on classic regulation, for the sole purpose of ensuring this function of security.

Les inconvénients inhérents à ces dispositifs connus ont donc conduit la Demanderesse à mettre au point un nouveau procédé de mise en sécurité anti-refoulement pour chauffe-bains et chaudières à gaz, de mise en oeuvre beaucoup plus simple puisque n'utilisant qu'un seul capteur de température placé dans le flux de refoulement des fumées.The disadvantages inherent in these devices known therefore led the Applicant to develop a new anti-backflow protection method for bath heaters and gas boilers, implementation much simpler since using only one sensor temperature placed in the flue gas discharge stream.

L'invention a donc pour objet un procédé de mise en sécurité de chauffe-bains et chaudières atmosphériques à gaz lors du refoulement des produits de combustion, mettant en oeuvre un seul capteur de température placé dans le flux de refoulement desdits produits de combustion, procédé qui consiste à interpréter à la fois les mesures de variation de température du capteur par rapport au temps et la mesure instantanée de la température des produits de combustion refoulés associée à l'information de la charge du brûleur pour que la mise en sécurité n'intervienne que si la mesure de la température est supérieure à un seuil déterminé correspondant à la puissance.The subject of the invention is therefore a method of placing in safety of atmospheric bath heaters and boilers gas during the discharge of combustion products, putting using a single temperature sensor placed in the flow delivery of said combustion products, process which consists in interpreting both the measures of variation of sensor temperature versus time and measurement temperature of the combustion products upsets associated with information on the burner load so that safety is only applied if the measurement of the temperature is above a determined threshold corresponding to the power.

D'autres caractéristiques de l'invention apparaítront à la lecture de la description qui va suivre d'un exemple de réalisation dans lequel il est fait référence aux dessins annexés qui représentent :

  • figure 1 une vue schématique en coupe de l'appareil en fonctionnement normal,
  • figure 2 la même vue montrant le refoulement des produits de combustion,
  • figure 3 une courbe illustrant la variation de température du capteur lors du refoulement des produits de combustion,
  • figure 4 un schéma illustrant la mise en sécurité de l'appareil lors d'un fonctionnement à petite puissance.
    • Other characteristics of the invention will appear on reading the following description of an embodiment in which reference is made to the accompanying drawings which represent:
  • FIG. 1 a schematic sectional view of the device in normal operation,
  • FIG. 2 the same view showing the discharge of the combustion products,
  • FIG. 3 a curve illustrating the temperature variation of the sensor during the delivery of the combustion products,
  • Figure 4 a diagram illustrating the safety of the device during operation at low power.

    • On a représenté partiellement à la figure 1 une chaudière équipée d'un brûleur 1, d'un corps de chauffe 2 à jupe chaude surmonté d'un boítier coupe-tirage 3 et d'un conduit 4 d'évacuation des fumées. Le boítier coupe-tirage dispose de façon connue d'entrées d'air latérales 5 et de déflecteurs 6 au-dessus de ces entrées d'air. Partly shown in FIG. 1 is a boiler equipped with a burner 1, a heating body 2 to hot skirt surmounted by a draft hood 3 and a smoke evacuation duct 4. The draft hood in known manner has side air inlets 5 and deflectors 6 above these air inlets.

    On place donc un capteur de température 7 en partie haute d'un déflecteur 6, c'est-à-dire dans une zone d'entrée d'air en fonctionnement normal, matérialisée par les flèches 8. Les produits de combustion ou fumées s'évacuent du corps de chauffe 2 vers le conduit d'évacuation 4, comme le montrent les flèches 9.We therefore place a temperature sensor 7 in upper part of a deflector 6, that is to say in an area air inlet in normal operation, materialized by arrows 8. Combustion or smoke products escape from the heating body 2 to the duct 4, as shown by arrows 9.

    Dans le cas d'un refoulement, d'un tirage insuffisant ou d'un bouchage du conduit 4, les fumées sont refoulées vers les entrées d'air 5 du boítier coupe-tirage et on voit à la figure 2 qu'elles lèchent le capteur de température 7. Le capteur se trouvant donc brusquement dans ce flux chaud, subit une variation de température qui est à l'image du refoulement des produits de combustion dans le local, comme l'illustre la courbe de la figure 3. Celle-ci montre la variation de la température T du capteur en fonction du temps t de fonctionnement de l'appareil.In the case of a refoulement, a draw insufficient or blockage of the duct 4, the fumes are discharged to the air inlets 5 of the draft hood and we see in Figure 2 that they lick the sensor temperature 7. The sensor therefore being suddenly in this hot flow undergoes a temperature variation which is at the image of the discharge of combustion products into the local, as illustrated by the curve in Figure 3. This shows the variation of the temperature T of the sensor in as a function of the device's operating time t.

    A partir d'un bouchage à un instant to, la température T va croítre rapidement puis se stabiliser à une valeur maximum.From a stopper at an instant to, the temperature T will grow quickly and then stabilize at a maximum value.

    Le procédé consiste à associer à cette mesure de la température T des fumées par le capteur, une information de puissance en charge du brûleur. La mise en sécurité de l'appareil n'aura lieu que si le capteur de température a détecté une variation rapide de la température et si la mesure de cette température est supérieure à un seuil T1 correspondant à un fonctionnement à petite puissance de l'appareil, ou à un seuil T2 pour un fonctionnement à grande puissance, ou un seuil intermédiaire pour une puissance intermédiaire.The method consists in associating with this measurement of the temperature T of the fumes by the sensor, information on the power under load of the burner. The device will be locked out only if the temperature sensor has detected a rapid change in temperature and if the measurement of this temperature is above a threshold T 1 corresponding to low power operation of the device, or at a threshold T 2 for high power operation, or an intermediate threshold for an intermediate power.

    Le seuil compris entre T1 et T2 est une fonction linéaire de la charge du brûleur et donc de la puissance de l'appareil. Il s'ajuste automatiquement en fonction de la puissance instantanée de l'appareil.The threshold between T 1 and T 2 is a linear function of the burner load and therefore of the power of the appliance. It adjusts automatically according to the instantaneous power of the device.

    Le schéma de la figure 4 montre qu'une instruction de mise en sécurité recueillie à la sortie ET est asservie à la variation de température dT / dt, qui dans le cas du fonctionnement à petite puissance pourrait être supérieure ou égale à 0,5° par seconde, de même qu'à la détermination de la température T qui doit être supérieure ou égale à la température T1. Dans le cas du fonctionnement à grande puissance la seule différence est que la température T doit être supérieure ou égale à la température T2.The diagram in FIG. 4 shows that a safety instruction collected at the ET output is subject to the temperature variation dT / dt, which in the case of operation at low power could be greater than or equal to 0.5 ° per second, as well as the determination of the temperature T which must be greater than or equal to the temperature T 1 . In the case of high power operation the only difference is that the temperature T must be greater than or equal to the temperature T 2 .

    A la figure 4, 10 est une dérivation et 11 un comparateur à hystérésis. Sur l'autre branche la référence 12 illustre la comparaison d'une température avec le seuil de coupure T. Après la sortie ET, la référence 13 représente l'autorisation d'allumage suivie du verrouillage 14 vers l'autorisation de demande d'allumage 15.In Figure 4, 10 is a derivation and 11 a hysteresis comparator. On the other branch, the reference 12 illustrates the comparison of a temperature with the threshold cutoff T. After the ET output, reference 13 represents ignition authorization followed by locking 14 towards authorization to request ignition 15.

    Lorsque le capteur détecte une variation àe température supérieure à 0,5° par seconde, la température n'a, en général, pas encore atteint le seuil de coupure T. En effet, lorsque la température du capteur dépasse le seuil de coupure, la variation dT / dt ou pente n'est plus que de l'ordre de 0,1° par seconde. Il faut donc mémoriser le fait que, à un moment, on a détecté une variation rapide de la température.When the sensor detects a change in temperature greater than 0.5 ° per second, the temperature has generally not yet reached the cutoff threshold T. When the temperature of the sensor exceeds the threshold the dT / dt variation or slope is no more than about 0.1 ° per second. So you have to memorize the fact that at one point there was a rapid change in the temperature.

    Ceci est réalisé à l'aide d'un comparateur à hystérésis 11 qui bascule à 1 lorsque la variation dT / dtest supérieure à 0,5° par seconde et qui ne basculera à 0 que si dT / dtdevient inférieure à -0,2° par seconde, En effet, si dT / dt reste supérieure à -0,2° par seconde, celà signifie que le bouchage perdure et qu'il faut arrêter l'appareil. Par contre si dT / dt devient inférieur à -0,2°C par seconde, cela signifie que le bouchage a été intermittent et il n'y a pas lieu de mettre en sécurité l'appareil. Cette mémorisation joue aussi le rôle de temporisation puisqu'elle laisse le temps au capteur d'atteindre la température seuil T.This is done using a comparator to hysteresis 11 which switches to 1 when the variation dT / dtest greater than 0.5 ° per second and which will only switch to 0 if  dT / dtd becomes less than -0.2 ° per second, Indeed, if dT / dt remains greater than -0.2 ° per second, this means that the clogging continues and the device must be stopped. By against if dT / dt becomes less than -0.2 ° C per second, this means that the blockage has been intermittent and there is no place to secure the device. This memorization also plays the role of time delay since it leaves the time for the sensor to reach the threshold temperature T.

    Cette solution présente l'énorme avantage d'être facilement et instantanément vérifiable, du point de vue électronique, à chaque demande d'allumage du brûleur.This solution has the enormous advantage of being easily and instantly verifiable from the point of view electronic, each time the burner is ignited.

    Le nouveau procédé apparaít toléranc pour les cheminées qui présentent un mauvais tirage à froid. En effet il faut une variation rapide de la température dT / dt pour empêcher l'appareil de fonctionner. Le seuil dT / dt est ajusté de façon à laisser le temps au tirage thermique de s'établir.The new process appears tolerant for chimneys with poor cold draft. Indeed a rapid variation of the temperature dT / dt is required for prevent the appliance from working. The dT / dt threshold is adjusted so as to allow time for thermal draft of settle down.

    Claims (3)

    1. Safety procedure for bath-water heaters and atmospheric gas boilers during the return of combustion products, employing a single temperature sensor placed in the return flow of the said combustion products, characterized in that it involves interpreting both the measurements of the variation dT / dt in temperature of the sensor in relation to time and the instantaneous measurement of the temperature (T) of the returned combustion products, in association with the measurement of the load of the burner, so that safety action takes place only if the measurement of the temperature is higher than a specific threshold corresponding to the power.
    2. Safety procedure according to Claim 1, characterized in that the threshold is between values (T1) and (T2) corresponding respectively to low-power and high-power operation of the appliance, and in that the threshold is a linear function of the load of the burner.
    3. Safety procedure according to Claim 1, characterized in that it involves storing the rapid temperature variation by means of a two-threshold hysteresis comparator which makes it possible to preserve the information relating to a rapid temperature variation characteristic of an obstruction of the smoke discharge duct.
    EP95402311A 1994-10-20 1995-10-17 Safety method for water heaters and atmospheric gas burners during the return of combustion gases Expired - Lifetime EP0708299B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    FR9412523A FR2726071B1 (en) 1994-10-20 1994-10-20 PROCESS FOR THE SECURITY OF GAS ATMOSPHERIC BATH HEATERS AND BOILERS DURING THE DISCHARGE OF COMBUSTION PRODUCTS
    FR9412523 1994-10-20

    Publications (2)

    Publication Number Publication Date
    EP0708299A1 EP0708299A1 (en) 1996-04-24
    EP0708299B1 true EP0708299B1 (en) 1998-12-30

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    EP95402311A Expired - Lifetime EP0708299B1 (en) 1994-10-20 1995-10-17 Safety method for water heaters and atmospheric gas burners during the return of combustion gases

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    EP (1) EP0708299B1 (en)
    AT (1) ATE175266T1 (en)
    DE (1) DE69506991T2 (en)
    ES (1) ES2126851T3 (en)
    FR (1) FR2726071B1 (en)

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    DE3020228C2 (en) * 1980-05-24 1984-08-09 Joh. Vaillant Gmbh U. Co, 5630 Remscheid Safety device for fuel-heated devices
    DE3527706A1 (en) * 1984-08-15 1986-02-27 Joh. Vaillant Gmbh U. Co, 5630 Remscheid Method for determining the switching-off criterion of a gas-heated device and circuit for implementing the method
    FR2596501B1 (en) * 1986-03-28 1990-04-27 Sdecc SAFETY DEVICE FOR A GAS BOILER OF THE TYPE WITH CONTROLLED MECHANICAL VENTILATION

    Also Published As

    Publication number Publication date
    FR2726071A1 (en) 1996-04-26
    DE69506991D1 (en) 1999-02-11
    DE69506991T2 (en) 1999-08-12
    FR2726071B1 (en) 1996-12-27
    ATE175266T1 (en) 1999-01-15
    EP0708299A1 (en) 1996-04-24
    ES2126851T3 (en) 1999-04-01

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