1、China September 20041Tour and AnderssonThe Three Hydronic Conditionsfor an accurate control in HVAC systems精確控制HVAC系統的三個水力工況條件Why and how to satisfy them in the simplest way為什么及如何用最簡單的方法滿足這些條件China September 20041Tour and China September 20042空調系統的目的All HVAC installations should reach 2 fundamental

2、objectives:所有空調采暖系統應達到兩個主要目的: To deliver the specified comfort level提供要求的舒適度 To reach the first objective, by consuming a minimum quantity of energy以最少的能耗達到以上目的Production冷熱源Distribution輸配系統Terminal units末端裝置China September 20042空調系統的目的AlChina September 20043理論和實踐In theory, current technology makes i

3、t possible to achieve these 2 objectives理論上,現代控制技術使實現這兩個目標成為可能In practice, even the most sophisticated control systems lead often to reduced comfort at increased operation costs但實際上,即使是最復雜的控制系統也不能帶來滿意的效果,而且運行成本較高China September 20043理論和實踐In tChina September 20044奇怪的現象 Too hot in some parts, too cold

4、 in others 在某些地方太熱, 在某些地方太冷 Start up after a set-back difficult in some rooms 在一些房間里回設之后的啟動比較困難 Installed power is not deliverable 裝機功率不能充分利用 Higher energy consumption than expected 比預期的能耗更高China September 20044奇怪的現象 TooChina September 20045奇怪的現象In most cases, solutions are to be found on the hydron

5、ic side在大部分案例中, 我們可以從水系統找到答案China September 20045奇怪的現象In mChina September 20046水力系統平衡簡介為什么水力系統要平衡？采暖及空調系統中水力平衡的技術是節能及提高供冷或供熱品質的關鍵常見的問題在供熱或空調系統中，由于種種原因，大部分輸送環路及冷熱源機組環路存在水力失調，使得流經終端用戶及機組的實際流量與設計流量不符。多數水泵選型偏大或水泵運行在不合適的工作點處，導致水系統處于大流量、小溫差運行工況，水泵運行效率低、熱量輸送效率低。各用戶處室溫不一致、不穩定，近熱源處室溫偏高，遠熱源處室溫偏低。近冷源處室溫偏低，遠冷源處

6、室溫偏高。對熱源或冷源機組來說，機組達不到其額定出力，使實際運行的機組臺數超過按負荷要求的臺數。China September 20046水力系統平衡簡介為China September 20047水力系統平衡的好處？采暖及空調系統中水力平衡的技術是節能及提高供冷或供熱品質的關鍵提高舒適度保證室溫達到設計要求，短時間內達到設定溫度流量分配合理水力平衡閥可以吸收超量壓差，還可以控制及設定系統所需的流量節約能量，降低運行費用在空調系統中溫度每降低1C，會造成能耗升高15%。在供熱系統中溫度每升高1 C，會造成能耗升高10%。水力系統平衡簡介China September 20047水力系統平衡簡介

7、China September 20048為什么水力系統要平衡？采暖及空調系統中水力平衡的技術是節能及提高供冷或供熱品質的關鍵水力系統平衡簡介China September 20048為什么水力系統要平China September 20049水力平衡系統的幾種方法？水力失調分為靜態水力失調與動態水力失調。靜態水力失調是指由于設計、施工、設備材料等原因導致的系統管道特性阻力數比值與設計要求的系統管道特性阻力數比值不一致，從而使系統各戶的實際流量與設計要求流量不一致，引起的水力失調，叫做靜態水力失調。靜態水力失調是穩態的、根本性的，是系統本身所固有的，是暖通空調水系統中水力失調的重要因素。通過在

8、管道系統中增設靜態水力平衡閥，在系統初調試過程中對系統管道特性阻力數比值進行調節，使其與設計要求一致，當系統總流量達到設計流量時，各空調單元也同時達到設計流量。水力系統平衡簡介China September 20049水力平衡系統的幾種China September 200410水力平衡系統的幾種方法？水力失調分為靜態水力失調與動態水力失調。動態水力失調是指系統實際運行過程中當某些閥門開度變化引起水流量改變時，系統的壓力產生波動，其他用戶的流量也發生改變，偏離系統要求流量，從而引起的水力失調，叫做動態水力失調。動態水力失調是動態的、變化的，不是系統本身所固有的，在系統運行的過程中產生的。通過在

9、管道系統中增設動態水力平衡設備，當其它用戶閥門開度發生變化時，通過動態水力平衡設備的屏蔽作用，使自身的流量不發生變化，末端流量不互相干擾。水力系統平衡簡介China September 200410水力平衡系統的幾China September 200411水力循環系統的三個條件The design flow must be available at all terminal units in design conditions所有末端裝置必須都能夠達到設計流量The differential pressure across the control valves must not vary t

10、oo much.通過控制閥的壓差不能有太大的變化The water flows must be compatible at system interfaces.一二次環路水流量必須一致China September 200411水力循環系統的三China September 200412第一個水力工況條件The design flow must be available at all terminal units in design conditions所有末端裝置必須都能夠達到設計流量第一個水力工況條件China September 200412第一個水力工況條China September

11、 200413“實用性” 優于同程系統對于需要安裝同程管道的同程系統，因為系統的不平衡較大的單元將得到更多的流量。只有在所有單元尺寸相等的情況下同程回路可達到平衡同程回路中各單元尺寸不一致不平衡同程管道China September 200413“實用性” 優于China September 200414自動流量平衡閥淘汰了同程管的使用，節余資金的同時提升系統的工作表現。“實用性” 優于同程系統自動平衡的異程回路同程回路連接不同型號的單元更好的工作狀態減少管路和投資China September 200414自動流量平衡閥淘China September 200415在亞洲通常還在使用同程系統

12、 + 手動平衡“實用性” 優于同程系統自動平衡的異程回路在同程系統應用手動平衡更好的工作狀態減少管路和投資China September 200415在亞洲通常還在使China September 200416手動平衡閥的安裝Branch BalancingValvesRiser BalancingValvesMain BalancingValveChina September 200416手動平衡閥的安裝China September 200417輸配系統FlowEmissionAt start-up, the first circuits are in overflow to the de

13、triment of the last ones.在剛開始啟動時,最近的回路發生過流而損害了最后的回路的流量.The start-up time will be longer for the last circuits.最不利環路的啟動時間將相對較長.An overflow does not necessarily mean an increased heat output.過流并不會成比例增加熱量的輸出China September 200417輸配系統FlowChina September 200418輸配系統When a plant is balanced, start-up can b

14、e achieved as required by design.當系統平衡時，起動將很快很好地達到設計所需的要求When a plant is unbalanced, it must be started earlier.當系統不平衡時，必須更早地開始工作（開機）.hoursExtra start-up timeunbalancedRoom temp.balanced24CChina September 200418輸配系統WhenChina September 200419輸配系統In many cases, the control system does not control the

15、two-way valves any longer :在許多情況下，控制系統根本不能很好地控制兩通閥門Start-up起動Sudden load variation負荷突然變化Weird set-point at the thermostat溫控裝置的不理想設置China September 200419輸配系統In mChina September 200420輸配系統 Each user adjusts the thermostat set-point according to his own feeling of comfort.每個用戶按照他自己的感覺和舒適度來調節溫控器的設置點.Th

16、is often leads to an uncontroled system.這經常導致系統的不平衡.Balancing allows to obtain the right room temperature everywhere.平衡將使每個房間獲得舒適的溫度% rooms 室內Room temperature 室內溫度 CUnbalanced不平衡Unbalanced,Supply t DecreasedBalanced平衡China September 200420輸配系統 EacChina September 200421不舒適的成本The cost of 1C too high r

17、oom temperature in winter: 6 to 11%在冬季室溫每升高1度的成本: 百分之6到11The cost of 1C too low room temperature in summer: 12 to 18%在夏季室溫每降低1度的成本:百分之12到18Unbalanced,Supply t decreasedBalanced平衡Unbalanced不平衡Room temperature 室內溫度 C% rooms 室內China September 200421不舒適的成本ThChina September 200422 AMETALTM alloy AMETALTM

18、 合金 Stem with EPDM O-ring頸部EPDM的O型圈Fast and easy to access self-sealing measuring nipples自密封測量口Draining cock泄水口Shut offValve關斷閥Fixedorifice固定孔板Valve with removedhandwheel手輪可卸Drain泄水閥All in one STAD、STAD囊括所有功能Mechanicalmemory機械式記憶裝置STAD平衡閥China September 200422 AMETALTChina September 200423STAD平衡閥Spr

19、ing for mechanical play tightening彈簧壓緊裝置Handwheel withdigital indication(80 setting positions)數字手輪（80個開度位置）Draining kit can be installed during operation使用中可安裝泄水裝置China September 200423STAD平衡閥SChina September 200424STAF 手動平衡閥160，240或者320位的數字式手輪，機械式記憶設置位置。快速方便的連接測量頭自平衡閥芯China September 200424STAF 手動平

20、China September 200425TA-CBI 儀表流量，壓差以及溫度測量快速設置計算機內置平衡法：TA平衡法 可與計算機通訊，配合TA Select II軟件編輯平衡數據 數據記錄（流量，壓差以及溫度）最多記錄24000個數據The advanced balancing instrument 先進的平衡儀器China September 200425TA-CBI 儀China September 200426TA-CMI 儀表 Flow, Dp and temp. Measurement 流量，壓差以及溫度測量 Viscosity correction (Glycol) 粘度修正（

21、乙二醇） Wireless communication 無線通訊The hydraulic multimeter多功能水力測量儀表China September 200426TA-CMI 儀China September 200427平衡選型軟件Calculation/Suggestion計算Info/technical documentation技術規格書List of selected products選擇結果Project/TA-CBI data項目/TA-CBI 數據TA Select IIChina September 200427平衡選型軟件CaChina September 20

22、0428平衡選型軟件TA Select II: Editing TA-CBI measured/logged dataTA Select II：編輯CBI測量/記錄的數據China September 200428平衡選型軟件TAChina September 200429Through balancing, many operational problems may be detected:通過平衡,許多運作問題可能被發現 Filters or valves clogged 過濾器或閥門阻塞 Terminal units or exchangers wrongly mounted 終端單元和

23、熱交換器的錯誤安裝 Pipe damaged or not connected as expected 管道損壞或安裝錯誤 Shut-off valves partially shut 截止閥不能關緊 Check valves or pumps installed back-to-front 止回閥或泵安裝方向錯誤Balancing exposes these flaws while they can still be cheaply repaired. 平衡診斷出了這些缺陷，而且它們能被輕易的改正診斷的要點Diagnostics is the 2nd main use of balancin

24、g valves. 系統診斷是使用平衡閥的另一個主要原因China September 200429Through China September 200430為什么要平衡 ?Adjusting the design flows in all terminal units in design conditions (when all control valves are fully open),while creating minimum additional pressure drops.調整每個末端的流量至設計流量（當控制閥全開時），同時產生最小的額外壓差1) Open a fortune

25、 cookie.2) Have a method.China September 200430為什么要平衡 ?China September 200431各式各樣的平衡方案3 kPa11 kPa10 kPa15 kPa22 kPa20 kPa15 kPa6 kPa2 kPa5 kPa4 kPa3 kPa10 kPa25 kPa= 43 kPa= 50 kPa= 65 kPa1.2.3.20 kPa15 kPa20 kPa18 kPa17 kPa22 kPa29 kPa33 kPa32 kPa37 kPa44 kPaChina September 200431各式各樣的平衡方China Sept

26、ember 200432分割成單元China September 200432分割成單元China September 200433分割成單元Simplifying the drawing is essential最關鍵的是簡化系統圖China September 200433分割成單元SimChina September 200434分割成單元China September 200434分割成單元China September 200435 Proportional method 比例法 adapted from air system balancing methodologies 采用空氣

27、系統平衡方法 not optimal in pressure drops 系統壓降方面不是最佳 Compensated method (Pr. Robert Petitjean) 補償法 designed for application with balancing valves 專門為設有平衡閥的系統而設計 optimal in pressure drops 系統壓降最優 TA Balance method (Pr. Robert Petitjean) TA平衡法 fully computerized: automatic determination of the index valve 全

28、電腦計算；自動判斷最不利環路 optimal in pressure drops 系統壓降最優系統平衡方法China September 200435 ProportChina September 200436平衡顯示了最佳的設置點Minimum pressure drops in the balancing valves(with the Compensated Method and TA-Balance)使通過平衡閥的壓降最小（補償法以及TA平衡法）All the pump head in excess islocated in the main valve所有過多的壓頭都位于主閥上Re-

29、open the main valveand adjust the pump speed重新開啟主閥，調整泵速123China September 200436平衡顯示了最佳的China September 200437實際案例Pfizer pharmaceutical production unit nearby Tours (France)圖爾斯（法國）附近的輝瑞制藥工廠 Installed cooling capacity of 5.4 MW (3 chillers in cascade) 總冷量5.4MW （3臺冷凍機并聯） Total design flow: 773 m/h 總設計

30、流量：773 m/h Problem: production alarms! 問題：生產線問題 80 TA balancing valves from STAD 15/14 to STAF 200 80個TA平衡閥，從STAD 15/14 到 STAF 200 Audit of plant with TA Circuit based on a first measurement campaign 利用TA Circuit 做系統評估 Presettings calculated with TA Circuit TA Circuit 計算出結果后進行預設定 Viscosity correctio

31、ns checked with TA Select II 利用TA Select II進行粘度修正 Full balancing performed using TA-Balance on one TA-CBI 利用一臺TA-CBI儀器完成了系統平衡的調試China September 200437實際案例PfizChina September 200438實際節約能耗Industrial plant5.4 MW cooling capacity889 m/h335 kPa pump headAFTERBalancing平衡后773 m/h (-13%)270 kPa pump head (-

32、20%)Pumping power saving 電力節約: 39 kWSavings 節約: 17200/yearBEFOREBalancing平衡前China September 200438實際節約能耗InChina September 200439實際案例Berlaymont Brussels 布魯塞爾(Belgium比利時)European Union Commission building歐盟總部242000 m; 3000 people70 interpreter rooms for simultaneous translation70個同聲翻譯室China September

33、200439實際案例BerlChina September 200440實際案例Berlaymont Brussels 布魯塞爾(Belgium比利時) 8.7 MW cooling capacity: 7.2MW centrifugal - glycolised water; 1.5 MW absorption 8.7 MW 制冷量： 7.2MW 離心機; 1.5 MW 溴化鋰吸收式制冷 Ice storage capacity: 324 tons of ice/day.畜冰量：324噸/天 7.8 MW heating capacity 7.8 MW 供熱量 8 floors with 1

34、200 cooling ceiling units per floor 8層樓，每層樓1200個左右末端 13000 TA balancing valves (STAD 10 to STAF 300) 總共13000個左右TA平衡閥 （ STAD 10 to STAF 300 ） 9730 TA terminal control valves + actuators 9730個TA末端控制閥以及執行器 Presettings calculated with TA Circuit TA Circuit 計算出結果后進行預設定 Full air and hydronic balancing ach

35、ieved by The CommTech Group 由CommTech 集團進行全面的空氣以及水力平衡 Hydronic balancing by 2 technicians with 2 TA-CBI 2位工程師用2臺CBI完成了整個系統的水力平衡China September 200440實際案例BerlChina September 200441第二個水力工況條件The differential pressure across the control valves must not vary too much.通過控制閥的壓差不能有太大的變化第二個水力工況條件China Septem

36、ber 200441第二個水力工況條China September 200442對非線性特性進行補償Cooling/heating coilControl valveControl is easy !供冷/供熱盤管調節閥控制非常容易！China September 200442對非線性特性進行China September 200443兩通調節閥閥權度The available Dp on a fully shut two-way control valve depends on the load conditions (i.e. on the opening of all other con

37、trol valves). 兩通閥全關時資用壓差取決于負荷情況（即取決于所有其它調節閥的開啟度The available Dp at one given location is:某一點的資用壓 min. at design conditions, 最小值：發生于設計工況下 max. for the min. total flow in the plant pump head. 最大值：發生于系統流量最小情況下 水泵揚程設計流量下調節閥全開時調節閥全關時China September 200443兩通調節閥閥權度China September 200444在現實條件下控制閥閥權度經常遠遠不能滿足

38、要求現實條件下, 兩通閥的尺寸選擇過大以及根據系統要求流量變化而變化的壓差導致閥權度遠達不到要求在較低的系統要求下, 只有很少的流量和管道摩擦力, 導致作用于控制閥的壓差增大一個很小的室溫的變化可觀的增加輸出能量結果 = 振蕩控制China September 200444在現實條件下控制China September 200445兩通調節閥閥權度Control valve authority should not be lower than 0.25控制閥閥權度不應低于0.25行程流量China September 200445兩通調節閥閥權度China September 200446壓差

39、的變化010203040506070809010011012013050100150200250300FlowHeat output50 % power20 % flow4% pressuredropAt 50 % of the heat output, the flow in the plant is only 20% of the design value and the pressure drops are reduced to 4%.All the available pump head applies itself on the 2-way control valves. 在50%熱

40、輸出時，系統中流量只有設計流量的20%，壓降降至設計壓降的4%。所有的水泵資用壓頭作用于兩通調節閥上。100%China September 200446壓差的變化010China September 200447控制質量下降Modulating control becomes ON/OFF ! FlowFlowOpeningOpeningPower50%9%34%50%開度調節型控制變成了開關型！功率流量開度流量China September 200447控制質量下降MoChina September 200448過低的閥權度使調節控制工作如開/關閥!變化的壓差造成的過低的閥權度導致昂貴的兩

41、通閥的工作狀態象便宜的開/關閥門結果 : 溫度高低波動TemperatureSet pointTimeTemperatureSet pointTimeTheoryRealityChina September 200448過低的閥權度使調China September 200449壓差的變化If C is less than 0.4, 如果C小于0.4,The differential pressure must be locally stabilised to ensure stable and accurate modulating control.則必須對壓差進行就地控制以確保穩定和精確的

42、調節型控制。How to determine in which plants differential pressure variations will significantly affect the controllability?Use the C coefficient:怎樣判斷在哪些系統中壓降的變化將顯著影響控制能力？利用系數C：設計水泵揚程最不利環路設計壓降China September 200449壓差的變化If China September 200450工作過程+-+-DPSTAPSTADFlow measurementDifferential pressureadjustm

43、entDH流量測量壓差調節China September 200450工作過程+-+-China September 200451工作過程pBpA= pA-pB = Circuit Dp for design flowDp STAPDp STAD Spring pushes to open the STAP. Secondary diff. pressure Dpl applies itself on the membrane: 二次側壓差p1作用于膜片上：When Dpl increases, the STAP shuts.當pl增加時，STAP關閉。When Dpl decreases,

44、the STAP opens.當pl減小時，STAP打開。在設計流量下環路壓降彈簧驅動打開STAP。pBpAChina September 200451工作過程pBpAChina September 200452壓力A通過與STAF的瀉水口(1)STAP的出水口(2)相連的毛細管傳導壓力B作用于閥芯隔膜(3)的另一側當作用于閥芯隔膜(3)壓差(AB)大于設定彈簧拉力時, 閥將逐漸關小只到到達新的平衡點(4)(3)AB(2)DpLH(1)(2)(4)BASTAP如何工作China September 200452壓力A通過與STChina September 200453STAP安裝在支路STA

45、PSTAD, STAM or STAFChina September 200453STAP安裝在支China September 200454平衡閥門設計流量 (100%)50% 設計流量部分流量時典型閥權度 手動平衡China September 200454平衡閥門設計流China September 200455自動平衡 (動態)設計流量 (100%)50% 設計流量部分流量時典型閥權度 自動平衡China September 200455自動平衡 (動態China September 200456壓差控制器 (STAP) 安裝于各個環路設計流量 100%50% 設計流量部分流量時典型閥

46、權度 STAP安裝在支路China September 200456壓差控制器 (SChina September 200457STAP安裝在各個盤管STAD, STAM or STAFSTAPChina September 200457STAP安裝在各China September 200458壓差控制器 (STAP) 安裝于各個控制閥 設計流量 100%50% 設計流量部分流量時典型閥權度 STAP安裝在各個環路China September 200458壓差控制器 (SChina September 200459 Stabilisation of the differential pre

47、ssure applied on the control valves. 穩定控制閥兩端的壓差 Ensures stable and accurate modulating control.確保穩定及精確的調節型控制 Reduces the risk of noise in terminal unit control valves.降低末端調節閥產生噪音的危險 Allows the shutting of 2-way control valves even for high pump heads.即使水泵壓頭很高,兩通閥也能關閉 Dynamic balancing 動態的平衡 Simple p

48、rocedure.平衡步驟簡單 Ideal for staged projects.對分期實施的項目效果更好差壓控制器的好處China September 200459 StabiliChina September 200460第三個水力工況條件The water flows must be compatible at system interfaces.一二次環路水流量必須一致第三個水力工況條件China September 200460第三個水力工況條China September 200461TA Autoflow 自動平衡閥AC & YR 型15 50mm易于拆卸的閥芯, 用于小口徑管

49、道WS 對夾型50 350mm使用多個80mm的閥芯,用于大口徑管道。China September 200461TA AutofChina September 200462TA Autoflow自動平衡閥 AC 型 15 50mm防脫鋅 (DZR)銅合金閥體, 英制標準螺紋接口。閥芯的筒體和彈簧由等級300的不銹鋼制成。彈簧閥芯測量點 關斷(球閥)接盤管的連接末端China September 200462TA AutofChina September 200463全 “自動” 操作 自動流量限制式平衡閥芯。平衡閥由工廠預設，避免在施工現場調整。China September 200463全

50、 “自動” 操China September 200464TA Autoflow 自動平衡閥自動限制流量China September 200464TA AutofChina September 200465TA Autoflow 自動平衡閥自動限制流量China September 200465TA AutofChina September 200466TA Autoflow 自動平衡閥自動限制流量China September 200466TA AutofChina September 200467TA Autoflow 自動平衡閥自動限制流量China September 200467T

51、A AutofChina September 200468TA Autoflow 自動平衡閥自動限制流量China September 200468TA AutofChina September 200469TA Autoflow 自動平衡閥自動限制流量China September 200469TA AutofChina September 200470不同壓差下工作狀態壓差超過最大設計要求，閥芯筒體全收縮-與節流孔板的功能一致。閥芯筒體根據壓差的變化調整開度精確保持設計流量在5%的范圍內。壓差低于最小設計要求，閥芯筒體全開-與節流孔板的功能一致。China September 200470

52、不同壓差下工作狀China September 200471不同壓差下工作狀態如下所示例子，壓差范圍14 210 kPaD Design FlowPressure drop (kPaD)14 (22)kPaD RangeMinimum210kPaD RangeMaximumFlow (L/s)Flow limiting zoneBest to avoid operating above control rangeChina September 200471不同壓差下工作狀China September 200472解決冷凍機分步啟動的問題在沒有自動平衡設備的條件下，即使每臺冷凍機都安裝一臺泵，

53、流量也會因為冷凍機分步啟動而產生波動。Chiller CondenserON10 L/sCooling Towers30L/sChiller CondenserON10 L/sChiller CondenserON10 L/sChina September 200472解決冷凍機分步啟China September 200473解決冷凍機分步啟動的問題對并聯運行的定流量水泵，總流量由總的阻力決定- 包括管道。HeadPressureTotal flow (l/s)System resistance curve30All units on03 Combined pumps head curve1

54、 pump head curve2 Combined pumps head curve1020Operating point all units runningChina September 200473解決冷凍機分步啟China September 200474解決冷凍機分步啟動的問題在系統沒有自動平衡的條件下，當部分設備關閉時，管道中流量減少，泵頭阻力減少，保持工作的泵加速運行產生過流。Chiller CondenserON17 L/sCooling Towers17L/sChiller CondenserOFF0 L/sChiller CondenserOFF0 L/sChina Sep

55、tember 200474解決冷凍機分步啟China September 200475解決冷凍機分步啟動的問題在沒有自動平衡設備的條件下，當管道中的流量降低，泵頭的壓力將導致泵速度的增加和持續工作設備的過流。HeadPressureTotal flow (l/s)System resistance curve30All units on03 Combined pumps head curve1 pump head curve2 Combined pumps head curve10Design 1 unit17Actual 1 unitOperating point 1 pumpChina S

56、eptember 200475解決冷凍機分步啟China September 200476解決冷凍機分步啟動的問題在冷機后安裝平衡閥可以有效地解決問題Chiller CondenserON10 L/sCooling Towers30L/sChiller CondenserON10 L/sChiller CondenserON10 L/sChina September 200476解決冷凍機分步啟China September 200477解決冷凍機分步啟動的問題當泵的工作數量變化時，自動平衡閥將根據系統阻力的變化調整以保持設計流量。HeadPressureTotal flow (l/s)System resistance curve30All units on03 Combined pumps head curve1 pump head curve2 Combined pumps head curve10Design 1 unitOperating point 1 pumpChina September 200477解決冷凍機分步啟China September 200478重要 : 檢查閥門的最小和最大 作用壓差在閥門的調整范圍內!最大kPaD將在一臺泵工作的時候得到。HeadPressur