NO179227B - Frost protection device for heat recoverers - Google Patents
Frost protection device for heat recoverers Download PDFInfo
- Publication number
- NO179227B NO179227B NO941913A NO941913A NO179227B NO 179227 B NO179227 B NO 179227B NO 941913 A NO941913 A NO 941913A NO 941913 A NO941913 A NO 941913A NO 179227 B NO179227 B NO 179227B
- Authority
- NO
- Norway
- Prior art keywords
- exhaust air
- heat exchanger
- frost protection
- air
- fan
- Prior art date
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 14
- 229910052782 aluminium Inorganic materials 0.000 description 14
- 238000010292 electrical insulation Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000009423 ventilation Methods 0.000 description 2
- 241000446313 Lamella Species 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F12/00—Use of energy recovery systems in air conditioning, ventilation or screening
- F24F12/001—Use of energy recovery systems in air conditioning, ventilation or screening with heat-exchange between supplied and exhausted air
- F24F12/006—Use of energy recovery systems in air conditioning, ventilation or screening with heat-exchange between supplied and exhausted air using an air-to-air heat exchanger
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
- F28F19/006—Preventing deposits of ice
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
- F24F11/41—Defrosting; Preventing freezing
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/56—Heat recovery units
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Air Conditioning Control Device (AREA)
- Greenhouses (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
- Other Air-Conditioning Systems (AREA)
- Defrosting Systems (AREA)
- Buildings Adapted To Withstand Abnormal External Influences (AREA)
- Cleaning Of Streets, Tracks, Or Beaches (AREA)
Description
Oppfinnelsen angår en frostsikringsanordning for varmegj envinnere. The invention relates to a frost protection device for heat exchangers.
Varmegjenvinnere oppbygget etter krysstrømprinsippet arbeider under normale forhold ved at varm avtrekksluft eller romluft passerer gjennom en varmevekslerkassett bestående av flere flate platekanaler. Kald uteluft eller tilluft passerer gjennom et tilsvarende sett med kanaler i samme varmevekslerkassett. Varmevekslerkassettens tverrsnitt er vanligvis rektangulær og avtrekksluftkanalene og tilløpskanalene ligger anordnet avvekslende etter hverandre med en lamelldelingsavstand. Heat recuperators built according to the cross-flow principle work under normal conditions by warm exhaust air or room air passing through a heat exchanger cassette consisting of several flat plate channels. Cold outside air or supply air passes through a corresponding set of channels in the same heat exchanger cassette. The cross-section of the heat exchanger cassette is usually rectangular and the exhaust air ducts and supply ducts are arranged alternately one behind the other with a lamella separation distance.
Kanalveggene i varmevekslerkassetten er normalt fremstilt av aluminium med liten platetykkelse, eksempelvis 0,1 mm. Dermed transporteres varme hurtig og lett gjennom platen, fra den ene til den andre side. Normale lufthastigheter i kanalene er i størrelsesordenen 1,5 m/s og virkningsgraden for varmeveksleren kan ligge på omkring 60%. The channel walls in the heat exchanger cassette are normally made of aluminum with a small plate thickness, for example 0.1 mm. In this way, heat is transported quickly and easily through the plate, from one side to the other. Normal air speeds in the ducts are of the order of 1.5 m/s and the efficiency of the heat exchanger can be around 60%.
Ved spesielle forhold mellom avtrekksluften og uteluften kan det dannes is i varmegjenvinnerens avtrekksluftkanaler, noe som kan innsnevre kanalene vesentlig og eventuelt tette dem. En slik situasjon oppstår typisk når utetemperaturen er lavere enn omkring -8°C og avtrekksluftens relative fuktighet er høyere enn 28%. Avtrekksluftens temperatur ligger i det vesentlige på omkring 20°C. For å hindre ising og tiltetting av avtrekksluf tkanalene, er det kjent å gjennomføre ulike tiltak. Ved hjelp av en termostat kan en vifte for uteluften stanses når luften i avtrekksluftkanalen synker til under et visst nivå og først igangsettes når temperaturen er kommet opp til et akseptabelt nivå. Videre kan en forvarming igangsettes når termostaten angir at avtrekksluftens temperatur er kommet under et fastlagt nivå. En kombinasjon av disse løsninger er likeledes mulig, fortrinnsvis i to trinn. Videre kan en føler registrere et trykkfall som måtte oppstå ved isdannelse, mens et tidrelé legger inn normal-funksjon når isen er smeltet. In special conditions between the exhaust air and outside air, ice can form in the heat recovery's exhaust air ducts, which can narrow the ducts significantly and possibly clog them. Such a situation typically occurs when the outside temperature is lower than around -8°C and the relative humidity of the exhaust air is higher than 28%. The temperature of the exhaust air is essentially around 20°C. In order to prevent icing and clogging of the exhaust air ducts, it is known to carry out various measures. With the help of a thermostat, a fan for the outside air can be stopped when the air in the exhaust air duct falls below a certain level and only started when the temperature has reached an acceptable level. Furthermore, preheating can be initiated when the thermostat indicates that the temperature of the exhaust air has fallen below a set level. A combination of these solutions is also possible, preferably in two stages. Furthermore, a sensor can register a pressure drop that may occur due to ice formation, while a time relay enters the normal function when the ice has melted.
Ved de tre først nevnte løsninger vil avstengningsfunk-sjoner ikke være nødvendig dersom avtrekksluften er tørr, noe som vil være det normale, også på kalde vinterdager. Viften for uteluft bør i slike tilfeller heller arbeide under normal drift og gi den ønskede, nødvendige ventilasjonbalanse. With the three first-mentioned solutions, shut-off functions will not be necessary if the exhaust air is dry, which will be normal, even on cold winter days. In such cases, the fan for outdoor air should rather work during normal operation and provide the desired, necessary ventilation balance.
Ved den sist nevnte løsning vanskeliggjøres en has-tighetsregulering av avtrekksluftviften og især tar det lang tid å smelte is som er dannet i så stor mengde at det registreres trykkfall. With the last-mentioned solution, it is difficult to regulate the speed of the exhaust air fan and, in particular, it takes a long time to melt ice that has formed in such a large amount that a pressure drop is registered.
Med frostsikringsanordningen ifølge foreliggende oppfinnelse unngås de ovenfor nevnte ulemper slik at varmegjenvinneren kan kjøre normalt over lengre tid og det dermed oppnås en vesentlig bedre utnyttelse av varmegjenvinneren samtidig som det opprettholdes en balansert og miljøriktig ventilasjon. Dette oppnås med f rostsikringsanordningen ifølge oppfinnelsen, slik den er beskrevet med de i kravene anførte trekk. With the frost protection device according to the present invention, the above-mentioned disadvantages are avoided so that the heat regenerator can run normally for a longer period of time and thus a significantly better utilization of the heat regenerator is achieved while at the same time a balanced and environmentally correct ventilation is maintained. This is achieved with the frost protection device according to the invention, as it is described with the features listed in the claims.
På tegningen viser figur 1 et snitt gjennom en varme-veksler med f rostsikringsanordningen innebygget, og figur 2 viser et forstørret snitt av lamellene i varmevekslerkassetten, med fuktføleren. In the drawing, figure 1 shows a section through a heat exchanger with the built-in frost protection device, and figure 2 shows an enlarged section of the slats in the heat exchanger cassette, with the moisture sensor.
Varm avtrekksluft suges av en avtrekksluftvifte 6 i varmeveksleren ut fra rommet eller huset gjennom en avtrekksluf tkanal 7, gjennom varmevekslerkassetten 1 og blåses ut gjennom avkastluftkanalen 8. Uteluft eller tilluft suges av en tilluftvifte 5 inn gjennom en uteluftkanal 9, gjennom varmevekslerkassetten 1 og blåses inn i rommet gjennom tilluftkanalen 10. Warm exhaust air is sucked by an exhaust air fan 6 in the heat exchanger out of the room or house through an exhaust air duct 7, through the heat exchanger cassette 1 and blown out through the exhaust air duct 8. Outside air or supply air is sucked in by a supply air fan 5 through an outside air duct 9, through the heat exchanger cassette 1 and blown in in the room through the supply air duct 10.
I varmevekslerkassetten 1 ligger avtrekksluftkanalene og tilluftkanalene avvekslende og er atskilt fra hverandre med kanalvegger 11. In the heat exchanger cassette 1, the exhaust air ducts and the supply air ducts lie alternately and are separated from each other by duct walls 11.
En frostsikringstermostat 3, 3' er fortrinnsvis anordnet i en avtrekksluf tkanal eller mellom en avtrekksluf tkanal og en avkastluftkanal og registrerer avtrekksluftens temperatur. En fuktføler 2 er anordnet i en avtrekksluftkanal og registrerer avtrekksluftens fuktighet. A frost protection thermostat 3, 3' is preferably arranged in an exhaust air duct or between an exhaust air duct and an exhaust air duct and registers the temperature of the exhaust air. A humidity sensor 2 is arranged in an exhaust air duct and registers the humidity of the exhaust air.
Fuktføleren 2 som er vist i snitt i figur 2, er oppbygget i en avtrekksluftkanal i varmevekslerkassetten med mot to motstående kassettvegger anliggende aluminiumsstrimler 14, mot aluminiumsstrimlene anliggende elektrisk isolasjon 12 og et i mellom de elektriske isolasjonssjikt 12 anordnet midtre aluminiumssjikt 15. Avtrekksluften vil stryke langs kanten av sjiktene 12, 14 og 15 på begge sider av disse og eventuell fuktighet i avtrekksluften vil avsettes på sjiktenes kanter. De ytre aluminiumssjikt 14 kan eksempelvis være av 0,5 mm aluminium og det kan ligge en spenning på 9 volt mellom de ytre aluminiumssjikt 14 og det midtre aluminiumssjikt 15. Det midtre aluminiumssjikt kan være 0,7 aluminium. The moisture sensor 2, which is shown in section in figure 2, is built in an exhaust air duct in the heat exchanger cassette with aluminum strips 14 attached to two opposite cassette walls, electrical insulation 12 attached to the aluminum strips and a central aluminum layer 15 arranged between the electrical insulation layers 12. The exhaust air will flow along the edge of the layers 12, 14 and 15 on both sides of these and any moisture in the exhaust air will be deposited on the edges of the layers. The outer aluminum layer 14 can, for example, be made of 0.5 mm aluminum and there can be a voltage of 9 volts between the outer aluminum layer 14 and the middle aluminum layer 15. The middle aluminum layer can be 0.7 mm aluminum.
Når fuktighet legger seg langs kantene av sjiktene, vil det mellom de ytre aluminiumssjikt 14 og det indre aluminiumssjikt 15 oppstå krypstrømmer over den elektriske isolasjon. Fuktighet vil især legge seg på oversiden 13 av sjiktene, men også på undersiden. Disse krypstrømmer vil kunne registreres ved at en spenning mellom de ytre aluminiumssjikt 14 og det midtre aluminiumssjikt 15 endres. When moisture settles along the edges of the layers, between the outer aluminum layers 14 and the inner aluminum layer 15 creep currents will arise over the electrical insulation. Moisture will settle in particular on the upper side 13 of the layers, but also on the underside. These creepage currents can be registered by changing a voltage between the outer aluminum layer 14 and the middle aluminum layer 15.
En elektrisk styringsanordning 4 er vist skjematisk i figur 1, som styrer viftefunksjonen på grunnlag av fuktfølerens 2 og frostsikringstermostatens 3, 3' registreringer. An electrical control device 4 is shown schematically in Figure 1, which controls the fan function on the basis of the moisture sensor 2 and frost protection thermostat 3, 3' registrations.
I tillegg til de på figur 1 viste følere, fuktføleren 2 og termostaten 3, 3', kan en temperaturføler registrere avkastluf tens temperatur. Selv om avkastluf tens temperatur skulle synke, vil tilluftviften 5 fortsette dersom fuktføleren 2 ikke registrerer fuktighet. Det vil dermed ikke foreligge fare for isdannelse. In addition to the sensors shown in figure 1, the humidity sensor 2 and the thermostat 3, 3', a temperature sensor can record the temperature of the exhaust air. Even if the temperature of the exhaust air should drop, the supply air fan 5 will continue if the humidity sensor 2 does not register humidity. There will therefore be no danger of ice forming.
Dersom imidlertid romluftens relative fuktighet øker på grunn av dusjing, klesvask og tørking etc, stanser tilluf tvif ten 5. En slik økning av fuktigheten vil være kortvarig og kun foregå korte perioder av døgnet. Dermed vil varmegjenvinneren kunne arbeide normalt over lengre tid. If, however, the relative humidity of the room air increases due to showering, laundry and drying, etc., supply air stops 5. Such an increase in humidity will be short-lived and only occur for short periods of the day. Thus, the heat recovery unit will be able to work normally for a longer period of time.
Dersom fuktføleren 2 registrerer vann eller fuktighet når frostsikringstermostaten 3, 3' registrerer en på forhånd gitt lav temperatur, stanses tilluftviften 5 og starter igjen når fuktføleren 2 ikke lenger registrerer fuktighet. If the moisture sensor 2 detects water or humidity when the frost protection thermostat 3, 3' detects a previously given low temperature, the supply air fan 5 is stopped and starts again when the moisture sensor 2 no longer detects humidity.
Dersom varmevekslerkassetten 1 skulle være nedkjølt til under frysepunktet ville tilluftviften 5 fortsette som normalt så lenge fuktføleren 2 ikke registrerer fuktighet. If the heat exchanger cassette 1 were to be cooled to below freezing point, the supply air fan 5 would continue as normal as long as the humidity sensor 2 does not register humidity.
Dersom det imidlertid foregår eksempelvis dusjing, vil den fuktige avtrekksluften kondensere med det samme den kommer inn i varmevekslerkassetten 1. Fuktføleren 2 som strekker seg gjennom hele varmevekslerkassetten, vil sikre at tilluftviften 5 stanser og hindrer dermed ytterligere isdannelse. However, if, for example, showering takes place, the moist exhaust air will condense as soon as it enters the heat exchanger cassette 1. The humidity sensor 2, which extends through the entire heat exchanger cassette, will ensure that the supply air fan 5 stops and thus prevents further ice formation.
Claims (1)
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NO941913A NO179227C (en) | 1994-05-24 | 1994-05-24 | Frost protection device for heat recoverers |
DE19581673T DE19581673C2 (en) | 1994-05-24 | 1995-05-23 | Frost protection device for heat recovery systems |
AU25808/95A AU2580895A (en) | 1994-05-24 | 1995-05-23 | Frost protection device for heat recovery plants |
PCT/NO1995/000080 WO1995032398A1 (en) | 1994-05-24 | 1995-05-23 | Frost protection device for heat recovery plants |
DK199601330A DK172963B1 (en) | 1994-05-24 | 1996-11-21 | Frost protection device for heat recovery plant |
FI964671A FI117647B (en) | 1994-05-24 | 1996-11-22 | Antifreeze for heat recovery installations |
SE9604294A SE507110C2 (en) | 1994-05-24 | 1996-11-22 | Anti-freeze device for heat recovery plants |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NO941913A NO179227C (en) | 1994-05-24 | 1994-05-24 | Frost protection device for heat recoverers |
Publications (4)
Publication Number | Publication Date |
---|---|
NO941913D0 NO941913D0 (en) | 1994-05-24 |
NO941913L NO941913L (en) | 1995-11-27 |
NO179227B true NO179227B (en) | 1996-05-20 |
NO179227C NO179227C (en) | 1996-08-28 |
Family
ID=19897117
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO941913A NO179227C (en) | 1994-05-24 | 1994-05-24 | Frost protection device for heat recoverers |
Country Status (7)
Country | Link |
---|---|
AU (1) | AU2580895A (en) |
DE (1) | DE19581673C2 (en) |
DK (1) | DK172963B1 (en) |
FI (1) | FI117647B (en) |
NO (1) | NO179227C (en) |
SE (1) | SE507110C2 (en) |
WO (1) | WO1995032398A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012032167A1 (en) | 2010-09-10 | 2012-03-15 | Flexit As | Ventilation system |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR19990043508A (en) * | 1997-11-29 | 1999-06-15 | 윤종용 | Evaporator temperature control method of air conditioner |
DE19954555C2 (en) * | 1998-11-25 | 2002-04-25 | Gerhard Feustle | Device and method for ventilation of a room with heat recovery |
DE20212619U1 (en) * | 2002-08-13 | 2003-10-16 | Meltem Waermerueckgewinnung Gm | Air exchange device, in particular for an interior of a building, with an air flow control |
DE102009032047B4 (en) * | 2009-07-07 | 2014-09-25 | Andreas Halmburger | Air exchange device for loading and / or venting a room |
CN104266316A (en) * | 2014-10-24 | 2015-01-07 | 中国扬子集团滁州扬子空调器有限公司 | Heat recovery control circuit for air conditioner |
CN106545947A (en) * | 2017-01-24 | 2017-03-29 | 北京代克环能技术有限公司 | A kind of anti-icing stifled heat-recovery fresh air ventilator of extremely frigid zones and its air exchanging method |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1923970A1 (en) * | 1969-05-10 | 1971-03-25 | Krupp Gmbh | Method and device for air conditioning |
JPS5818566B2 (en) * | 1976-07-08 | 1983-04-13 | ダイキン工業株式会社 | heat recovery equipment |
SE402486B (en) * | 1976-11-09 | 1978-07-03 | Svenska Flaektfabriken Ab | VERMEAT RECYCLING FACILITY |
DE3224635A1 (en) * | 1981-10-23 | 1983-05-05 | Mitsubishi Denki K.K., Tokyo | VENTILATION DEVICE |
US4971137A (en) * | 1989-11-09 | 1990-11-20 | American Energy Exchange, Inc. | Air-to-air heat exchanger with frost preventing means |
-
1994
- 1994-05-24 NO NO941913A patent/NO179227C/en not_active IP Right Cessation
-
1995
- 1995-05-23 AU AU25808/95A patent/AU2580895A/en not_active Abandoned
- 1995-05-23 WO PCT/NO1995/000080 patent/WO1995032398A1/en active IP Right Grant
- 1995-05-23 DE DE19581673T patent/DE19581673C2/en not_active Expired - Lifetime
-
1996
- 1996-11-21 DK DK199601330A patent/DK172963B1/en not_active IP Right Cessation
- 1996-11-22 SE SE9604294A patent/SE507110C2/en not_active IP Right Cessation
- 1996-11-22 FI FI964671A patent/FI117647B/en not_active IP Right Cessation
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012032167A1 (en) | 2010-09-10 | 2012-03-15 | Flexit As | Ventilation system |
Also Published As
Publication number | Publication date |
---|---|
FI964671A (en) | 1996-11-22 |
DK172963B1 (en) | 1999-10-25 |
NO941913L (en) | 1995-11-27 |
SE9604294L (en) | 1996-11-22 |
SE9604294D0 (en) | 1996-11-22 |
DE19581673C2 (en) | 2001-08-16 |
AU2580895A (en) | 1995-12-18 |
FI964671A0 (en) | 1996-11-22 |
DE19581673T1 (en) | 1997-06-05 |
NO179227C (en) | 1996-08-28 |
SE507110C2 (en) | 1998-03-30 |
FI117647B (en) | 2006-12-29 |
NO941913D0 (en) | 1994-05-24 |
WO1995032398A1 (en) | 1995-11-30 |
DK133096A (en) | 1996-11-21 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
MK1K | Patent expired |