INSTALLATION AND MAINTENANCE INSTRUCTIONS IM-5-200-US October 2015 Pressure Powered Pump™ PPEC Safe operation of these products can be guaranteed only if they are properly installed, commissioned, used and maintained by qualified personnel (see point 11 on this document) in compliance with the operating instructions. General installation and safety instructions for pipeline and plant construction, as well as the proper use of tools and safety equipment, must also be complied with. 1.5 Hazardous environment around the product 1. Intended use Referring to the Installation and Maintenance Instructions, Nameplate and Technical Information Sheet, check that the product is suitable for the intended use/application. The products listed below comply with the requirements of the European Pressure Equipment Directive 97/23/EC and carry the CE when so required. The products fall within the following Pressure Equipment Directive categories: Product PPEC I) II) Group 2 Gases Iron Steel N/A II The products have been specifically designed for use on steam, air and inert industrial gases which are in Group 2 of the above mentioned Pressure Equipment Directive. The product’s use on other fluids may be possible but, if this is contemplated, Spirax Sarco should be contacted to confirm the suitability of the product for the application being considered. Check material suitability, pressure and temperature and their maximum and minimum values. If the maximum operating limits of the product are lower than those of the system in which it is being fitted, or if malfunction of the product could result in a dangerous overpressure or overtemperature occurrence, ensure a safety device is included in the system to prevent such over-limit situations. III) Determine the correct installation situation and direction of fluid flow. IV) Spirax Sarco products are not intended to withstand external stresses that may be induced by any system to which they are fitted. It is the responsibility of the installer to consider these stresses and take adequate precautions to minimise them. Remove protective covers from all connections before installation. V) 1.2Access Ensure safe access and if necessary a safe working platform (suitably guarded) before attempting to work on the product. Arrange suitable lifting gear if required. 1.3Lighting Ensure adequate lighting, particularly where detailed or intricate work is required. 1.4 Hazardous liquids or gases in the pipeline Consider what is in the pipeline or what may have been in the pipeline at some previous time. Consider: flammable materials, substances hazardous to health, extremes of temperature. Consider: explosion risk areas, lack of oxygen (e.g. tanks, pits), dangerous gases, extremes of temperature, hot surfaces, fire hazard (e.g. during welding), excessive noise, moving machinery. 1.6 The system Consider the effect on the complete system of the work proposed. Will any proposed action (e.g. closing isolation valves, electrical isolation) put any other part of the system or any personnel at risk? Dangers might include isolation of vents or protective devices or the rendering ineffective of controls or alarms. Ensure isolation valves are turned on and off in a gradual way to avoid system shocks. 1.7 Pressure systems Ensure that any pressure is isolated and safely vented to atmospheric pressure. Consider double isolation (double block and bleed) and the locking or labelling of closed valves. Do not assume that the system has depressurised even when the pressure gauge indicates zero. 1.8Temperature Allow time for temperature to normalise after isolation to avoid danger of burns. 1.9 Tools and consumables Before starting work ensure that you have suitable tools and / or consumables available. Use only genuine Spirax Sarco replacement parts. 1.10 Protective clothing Consider whether you and / or others in the vicinity require any protective clothing to protect against the hazards of, for example, chemicals, high / low temperature, radiation, noise, falling objects, and dangers to eyes and face. 1.11 Permits to work All work must be carried out or be supervised by a suitably competent person. Installation and operating personnel should be trained in the correct use of the product according to the Installation and Maintenance Instructions. Where a formal ‘permit to work’ system is in force it must be complied with. Where there is no such system, it is recommended that a responsible person should know what work is going on and, where necessary, arrange to have an assistant whose primary responsibility is safety. Post ‘warning notices’ if necessary. 1.12Handling Manual handling of large and/or heavy products may present a risk of injury. Lifting, pushing, pulling, carrying or supporting a load by bodily force can cause injury particularly to the back. You are advised to assess the risks taking into account the task, the individual, the load and the working environment and use the appropriate handling method depending on the circumstances of the work being done. 1.13 Residual hazards Steam Mains - Do's and Dont's: In normal use the external surface of the product may be very hot. If used at the maximum permitted operating conditions the surface temperature of some products may reach temperatures in excess of 300°C (572°F). 4 7 4 7 4 7 4 7 4 7 Many products are not self-draining. Take due care when dismantling or removing the product from an installation (refer to 'Maintenance instructions'). 1.14Freezing Provision must be made to protect products which are not self-draining against frost damage in environments where they may be exposed to temperatures below freezing point. Steam 1.15Disposal Unless otherwise stated in the Installation and Maintenance Instructions, this product is recyclable and no ecological hazard is anticipated with its disposal providing due care is taken. 1.16 Returning products Customers and stockists are reminded that under EC Health, Safety and Environment Law, when returning products to Spirax Sarco they must provide information on any hazards and the precautions to be taken due to contamination residues or mechanical damage which may present a health, safety or environmental risk. This information must be provided in writing including Health and Safety data sheets relating to any substances identified as hazardous or potentially hazardous. 1.17 Working safely with cast iron products on steam Cast iron products are commonly found on steam and condensate systems. If installed correctly using good steam engineering practices, it is perfectly safe. However, because of its mechanical properties, it is less forgiving compared to other materials such as SG iron or carbon steel. The following are the good engineering practices required to prevent waterhammer and ensure safe working conditions on a steam system. Prevention of tensile stressing Pipe misalignment: Installing products or re-assembling after maintenance: 1 Safe Handling Cast Iron is a brittle material. If the product is dropped during installation and there is any risk of damage the product should not be used unless it is fully inspected and pressure tested by the manufacturer. 4 7 Do not over tighten. Use correct torque figures. Prevention of water hammer Steam trapping on steam mains: 30 - 50 metre intervals Gradient Steam 1:100 Trap set Condensate 2 Gradient 1:100 Trap set Condensate Steam Trap set Condensate 7 3 2 1 3 5 6 4 2 8 Flange bolts should be gradually tightened across diameters to ensure even load and alignment. Thermal expansion: Guides Limit rods Guides Medium distance Axial movement Short distance Small lateral movement Large lateral movement Fixing point Fixing point Limit rods Axial movement Guides Guides Small lateral movement Large lateral movement Operating Pressure Range 5 to 125 psi (.34 to 8.6 bar) How Pressure Powered Pump™ Operates 1. In the normal position before start-up the float (5) is at its lowest position with the steam valve (6) closed and exhaust valve (7) open. 2. When liquid flows by gravity through inlet check valve (8) into pump body, the float (5) will become buoyant and rise. 3. As the float (5) continues to rise the mechanism link (3) is engaged which increases the tension in the springs (15). When the float (5) has risen to its upper tripping position the energy in the springs is released instantaneously causing the linkage mechanism (3) to snap upwards over center moving push rod upwards to simultaneously open steam inlet valve and close exhaust valve. 4. Steam will now flow through the steam valve (6) and develop a pressure within the body forcing the liquid out through the dis- PPEC Operating Pressure Inlet (Front Face) charge check valve (9). The inlet check valve (8) will be closed during the discharge cycle. 5. As the liquid level in the pump body decreases so does the float’s position. Before the float reaches its lowest position the mechanism link (3) is engaged increasing the tension in the springs (15). When the float is at its lower tripping position in the body the energy in the springs is released instantaneously causing the linkage mechanism (3) to snap over center downward moving push rod down causing the steam valve (6) to close and exhaust valve to open simultaneously. 6. Liquid will again flow through inlet check valve (8) to fill pump body and the cycle will be repeated. 6 Exhaust Outlet 1A 1 3 15 0.100” 7 12 13 9 Liquid Outlet 5 8 8 Liquid Inlet 3 10 Installation — Vented Systems (Fig. 2) Check valve to help reduce likelihood of backflow and waterhammer. Operating Steam or Gas Supply Vent to atmosphere. Vent to be piped to a safe location such that there is no risk to personnel. Vent head recommeded if vent not piped to a pit or similar location. Pump Exhaust Condensate Return Line Condensate Vented Receiver H Height Filling Head 6” Preferred At least 12” Seal on overflow. Discharge to be piped to safe location such that there is no risk to personnel. Inlet Strainer TD 42L or 52L Trap When steam supply is used Figure 2 Recommended installation of pressure powered pump when fitted with a reservoir or vented receiver. In an “open” system flash steam must be vented or condensed ahead of pump inlet. Application details will dictate which of the following options will be necessary to accomplish this. Caution: Before installation or any maintenance is performed, ensure that all condensate, steam, air or gas lines are closed to prevent personnel injury. It is highly recommended by Spirax Sarco that an adequately sized overflow is fitted to all condensate receivers. This should be considered best practice and overflows should only be excluded from installations in exceptional circumstances. Discharge from both overflows and vent pipes MUST be piped to a safe location, such that there is no risk to personnel. In the event of pump or system malfunction or overload, very hot condensate may be discharged from the overflow, or the vent pipe, or both. Where the vent pipe is not piped to a pit, or similar safe location, the use of a vent head to reduce the chance of entrained hot condensate spraying out of the vent is recommended. Overview Connection — Overflow piping must be used on a vented system. Over-flow connections are required to ensure that in the event of pump or system malfunction, condensate will run in a controlled manner, from the condensate receiver to a safe location, such as a drain (subject to temperature and local regulations) or to an alternative safe location. The overflow piping must be a ’U’ bend water seal which has a 12” minimum depth. Once primed on start-up the water seal is self-filling and should be piped to a suitable drain. The addition of the overflow provides a safety mechanism ensuring the pressure within the receiver does not increase. The overflow is also a tool to diagnose system problems. In the event of the overflow spilling fluid the operator is immediately made aware of a system problem. This could include failed traps feeding the package failed pump and changes in system loads and overloaded receiver. Pump or system malfunction which could cause the receiver to over-flow, can occur for many reasons. These including, loss of motive steam due to blockage or incorrect operation, mechanical failure of the pump mechanism or associated check valves, blockage of the condensate inlet strainer of closure of the pumped return line and system shutdowns. Over-flows will normally be a minimum of 1 1/2 “ (DN40) in diameter, but may need to be larger for high capacity units such as packaged PTF4, or where the length of over flow pipe run, between receiver and discharge point, is more than 2 meters (6 ft.). A general “rule of thumb” (based on a 2 m (6 ft.) pipe run and a head of 0.6 m (2 ft.). Condensate loads from zero to 5000 l/hr. (zero to 11000 lb. /hr.) use 1½” Condensate loads from 5000 I/hr.to 10000 I/hr. (11000 to 22000 lb. /hr.) use 2” Condensate loads from 10000 to 18000 I/hr. (22000 to 39600 lb. / hr.) use 3” Normally over-flow connections will be fitted with a “loop seal” arrangement or a suitably sized float trap, to prevent steam escaping via the over-flow connection. 1.Install the pump physically below the receiver to be drained with the exhaust connection (10) vertically upwards. Pump should be installed with the recommended filling head (the vertical distance between the top of the pump and the bottom of the receiver) as shown in Fig. 2.For other filling head variations, see the capacity table on TI-5-202-US. Recommended Filling Head: 3/4” & 1” PPEC 6” 2.To prevent equipment flooding during the pump discharge stroke, a vented receiver should be installed in a horizontal plane ahead of the pump as shown in Figure 2. For proper receiver sizing, refer to the table shown below. All inlet line fittings must be fully ported. 4 Vented Receivers To drain condensate from single or multiple sources in an “open” system, a vented receiver should be installed in a horizontal plane ahead of the pump. Sufficient volume is needed above the filling head level to accept the condensate reaching the receiver during the pump discharge stroke. More importantly, the receiver must be sized to allow sufficient area for complete flash steam separation from the condensate. The chart below shows proper vented receiver sizing (per criteria set forth in the A.S.H.R.A.E. Handbook) based on the amount of flash steam present. By sizing the receiver as shown below, there will be sufficient volume for condensate storage and sufficient area for flash steam separation. The receiver can be a length of large diameter pipe or a tank. If desired, receiver overflow piping can be installed as shown in Fig. 2 and piped to a suitable drain. The piping must form a loop type water seal at least 12” deep immediately after the receiver. Pump Size Flash Steam Up to 75 pph 150 pph 300 pph 600 pph 900 pph 5 Receiver Vent Line DiameterLength Diameter 3” 30” 1-1/2” 4” 30” 2” 6” 36” 2-1/2” 8” 36” 3” 10” 36” 4’ 3. Connect the vented receiver to the inlet check valve on the pump. Connect the discharge to the return main or other installation point. For best performance, horizontal piping runs immediately ahead of the inlet check valve and after the discharge check valve should be kept to a minimum. Connect the discharge to the return main or other installation point. Note:To achieve rated capacity, pump must be installed with check valves as supplied by Spirax Sarco,Inc., except, at inlet on sump pit application as shown in Fig. 9. 4. Connect the operating medium (steam, air or gas) supply to the motive supply inlet in the cover. Supply main should have a strainer and steam trap (steam service) or drain trap (air or gas service) installed upstream of the supply inlet. The steam trap/drain trap discharge should be piped into the receiver ahead of the pump for steam systems. Note:When available motive pressure exceeds 125 psi, a Spirax Sarco pressure reducing valve is required to reduce pressure to the pump. The PRV should be located as far from the pump as possible. For best operation, motive pressure should be reduced to the minimum required to overcome pump back pressure and achieve the desired capacity. A safety relief valve should be installed at the connection provided in the pump cover or in the motive supply piping. 5.Exhaust line should be piped, unrestricted, to atmosphere. Line should be vertical, if possible. If horizontal runs must be used, line should be pitched so that it is self draining to the pump or receiver. Installation — Closed Loop Systems (Figs. 3 or 4) A closed-loop installation is one in which the exhaust line of the pump is piped back (pressure equalized) to the steam space being drained. Caution:Before installation or any maintenance is performed, ensure that all steam, condensate, air or gas lines are closed to prevent personnel injury. 1. Install the pump physically below the equipment being drained with the exhaust connection (10) vertically upwards. Pump should be installed with the recommended filling head (the vertical distance between the top of the pump and the bottom of the reservoir) as shown in Fig. 3. For other filling head variations, see Capacity Table on TIS 5.202. Recommended Filling Head: 3/4” & 1” PPEC 6” 2.To prevent equipment flooding during the pump discharge stroke, a reservoir pipe should be installed in a horizontal plane ahead of the pump as shown in Fig. 3. For proper reservoir sizing, refer to “Inlet Reservoir Piping” table shown on this page. All inlet line fittings must be fully ported. If desired, overflow piping can be installed using a properly sized float and thermostatic trap. The trap inlet should be located at the maximum allowable water level, at or near the top of the reservoir, and it should discharge to a suitable drain. 3. Connect the check valves (8) and (9) to the pump, making sure that the flow through the valves is in the proper direction. For best performance, horizontal piping runs immediately ahead of the inlet check valve and after the discharge check valve should be kept to a minimum. Connect the discharge to the return main or other installation point. Note: To achieve rated capacity, pump must be installed with check valves as supplied by Spirax Sarco, Inc. 4.Connect the operating medium (steam only) supply to the motive supply inlet in the cover. Supply main should have a strainer and steam trap installed upstream of the supply inlet. The steam trap discharge should be piped to the downstream piping (Nonflooded). Note:When available motive pressure exceeds 125 psi, a Spirax Sarco pressure reducing valve is required to reduce pressure to the pump. The PRV should be located as far from the pump as possible. For best operation, motive pressure should be reduced to the minimum required to overcome backpressure and achieve desired capacity. A safety relief valve should be installed at the connection provided in the pump cover or in the motive steam supply piping. 5. Exhaust line must be piped, unrestricted, to the steam space being drained. The exhaust line can be connected to the top of the reservoir pipe when a proper connection in the steam space is not available. A thermostatic air vent should be installed at the highest point of the exhaust line to vent all non-condensibles during start-up. Any horizontal runs in exhaust line should be pitched so that the line is self-draining. 6.If at any time the backpressure against the pump is less than the pressure in the equipment being drained, a properly sized float and thermostatic trap must be installed between the pump and discharge check valve as shown in Figure 4. Inlet Reservoir Piping To drain condensate from a single piece of equipment in a “closed system”, a reservoir should be installed in a horizontal plane ahead of the pump. Sufficient reservoir volume is needed above the filling head level to accept condensate reaching the pump during the discharge stroke. The chart below shows minimum reservoir sizing, based on condensate load, needed to prevent equipment flooding during the pump discharge stroke. The reservoir can be a length of large diameter pipe or a tank. Feet of reservoir piping needed for... Pump Size Liquid P ipe Size Lb. per Hr. 1-1/2”2”3”4”6” 500 or less 2’ 10003’ 2’ 15005’ 3’ 2000 6’4’2’ 3000 6’ 3’ 4000 8’ 3.5’2’ 5000 10’ 4.5’2.5’ 6000 5.5’3’ 7000 6’ 3.5’ 8000 7’ 4’ P1 Return Line Balanced Pressure Thermostatic Air Vent Pilot Operated Temperature Control Valve 1/2” HP Steam Supply Heat Exchanger Reservoir Filling Head Spira-tec Steam Trap Loss Detector Pressure Powered Pump Draining L.P. Heat Exchanger to Overhead Return. Pressure at PP Pump outlet P2 exceeds pressure of supply to Heat Exchanger P1. P2 Thermo-Dynamic® Trap Figure 3 6 Startup Procedure (All Hookups) P1 Balanced Pressure Thermostatic Air Vent Steam Supply Wye Strainer Pilot Operated Temperature Control Valve Temperature Control Sensor Return Flow Heater Centrifugal Pump Reservoir Pipe Steam Supply Pressure Powered Pump Figure 4 Draining L.P. Heat Exchanger to Overhead Return. Pressure at PP Pump outlet P2 does not exceed pressure of supply to Heat Exchanger P1. P2 1. Slowly open supply (steam, air or gas) to provide pressure at the PP Pump inlet valve. Check that trap/drainer on motive line is operational. 2. Open gate valves in the PP Pump inlet and discharge lines. 3. Open valve(s) ahead of unit allowing condensate to enter the receiver/reservoir and fill the PP Pump body. Pump will discharge when full. 4. Observe operation for any abnormalities. PP Pump(s) should cycle periodically with an audible exhaust at the end of the pumping cycle. If any irregularities are observed, recheck installation instructions for proper hookup. Consult factory if necessary. 5. If overflow piping has been provided, check that a water seal has been established to prevent any steam from being vented during normal operation. Prime overflow piping if necessary. Float & Thermostatic Steam Trap Maintenance: Inspection & Repairs CAUTION: Before removing the cover and mechanism assembly, be sure that the pump is completely isolated and relieved of any internal pressure. Motive supply, exhaust/tie-back, condensate inlet, and discharge lines should all be closed prior to performing any work on the pump. Use caution when removing cover and gasket. Gasket contains thin stainless steel reinforcement that may cause cuts to the skin. 1.Break all connections to the cover. Remove cover bolts and lift the cover and mechanism assembly from the body, noting the cover orientation. 2.Visually inspect the mechanism to verify that it is free of dirt and scale and moves freely. 3.Visually check springs (15). If defective, remove retaining clips and slide spring from pins. Replace with new springs (if necessary) and install retaining clips. 4.To check inlet and exhaust valves: a.Remove the mechanism casting securing bolts (13). Carefully lift mechanism assembly free from cover. NOTE: Mechanism assembly is factory set and tested. No adjustments to the mechanism assembly should be made. If required, entire cover and mechanism assembly should be returned to the factory for repair service. Inlet Seat 85-90 ft-lb 7 Exhaust Seat 85-90 ft-lb b.Visually inspect seating surfaces of inlet and exhaust valves for signs of wear (inlet valve assembly must be removed to check seat). Clean seating areas and reinstall or replace if necessary. When replacing steam or exhaust valve heads or seats, make certain the actuator disc (12) is adjusted as shown in drawing on page one. Torque seats as shown in table below. The float must be in the down position when making this adjustment. c.To reassemble, reverse the above procedure. Replace gaskets. 5.When reinstalling cover and mechanism assembly, cover should be oriented as noted (1) above. Follow the start-up procedure to bring the pump back in operation. Torque cover bolts as shown on previous page. For use of these units in hookups other than those described and illustrated, and for any additional information you may require, contact Spirax Sarco Applications Engineering Department, toll free: 1-800-833-3246 PPEC Cover Bolts 175-185 ft-lbs Pressure Powered Pump™ Troubleshooting Checklist If a correctly sized Pressure Powered Pump does not operate properly, an incorrect hookup is suspect in new installations. For existing installations where the pump operates occasionally or not at all, the cause is often a change in the system supply or back pressure conditions beyond the original design parameters. With the system conditions and problem symptoms determined, check the following in turn and correct as necessary. Symptom 1.Pump fails to operate on startup. Check and Cure 1.a) Open valve(s) to supply motive pressure to pump. b) Open all valves to allow condensate to reach pump. b) Condensate inlet line closed. c) Condensate discharge line closed. c) Open all valves to allow free discharge from pump to destination. d) Check motive pressure and static backpressure. d) Motive pressure insufficient to Adjust motive pressure to 10-15 psi higher than static overcome backpressure. backpressure. e) Check valves(s) installed in wrong e) Verify proper flow direction and correct, if required. direction. f) On vented system, assure that vent line is unrestrictf) Pump air-locked. ed to atmosphere and self-draining to the pump or receiver. On a closed system, isolate the pump from the pressurized space being drained. (Exhaust tieback line closed.) Break exhaust connection at pump cover. Keep personnel clear of exhaust connection. If pump begins to cycle, air locking has occurred. Recheck that exhaust tie-back is in accordance with the installation instructions. Install a thermostatic air vent at a high point in the exhaust line. Assure that the equalizer line is self-draining. 1.a) Motive supply closed. 2.a) Verify rate capacity per TIS 5.202 capacity table. Increase check valve size or install additional pump as required. b) Verify required filling head per TIS 5.202. Lower pump b) Insufficient filling head. to achieve required filling head. c) Check motive pressure setting and maximum backc) Insufficient motive pressure to pressure during operation. Compare to capacity table achieve rated capacity. of TIS 5.202. Increase motive pressure as required to meet load conditions. d) Restriction in condensate inlet line. d) Verify that fully ported fittings are used. Blowdown the strainer, if fitted. Check that all valves are fully open. e) Isolate inlet check valve and relieve line pressure. e) Inlet check valve stuck open Remove cap an visually inspect head, seat, and stem. (debris). Clean seating surfaces and reinstall or replace, if necessary. 2.a) Pump undersized. 3.Supply line/equipment flooded, and pump has stopped cycling (audible periodic exhaust not observed). Installation and troubleshooting should be performed by qualified service personnel. Before breaking any connections of the pump or piping system every effort should be made to assure that internal pressure has been relieved and that the motive supply line is shut off to prevent inadvertent discharge of the pump. When breaking any connection, piping/bolts should be removed slowly so that if the line is under pressure, this fact will be apparent before completely removing the pipe or component. Always relieve pressure before breaking any joint. Cause 2.Supply line/equipment flooded, but pump appears to cycle normally (periodic audible exhaust observed). CAUTION: 3.a) Discharge line closed or blocked. b) Discharge check valve stuck closed. c) Insufficient motive pressure. 3.a) Check motive pressure and static back-pressure (at pump discharge). If equal, a closed or blocked discharge line is suspected. Check all valves downstream of pump to assure an unobstructed discharge. b) After checking per 3(a), isolate discharge check valve and relieve line pressure. Visually inspect head, seat and stem. Clean seating surfaces and reinstall or replace, if necessary. c) If motive pressure is below static backpressure, increase motive pressure setting to 10-15 psig above static backpressure. Do not exceed rated pressure limits of equipment. For steps 3(d) through 3(g) on page 7—With exhaust/ tie-back line isolated from the equipment being drained (close-loop systems), break the exhaust/tieback connection at the pump cover and— 8 Symptom Important Safety Note: For steps (d) through (g) it is necessary to break the exhaust/tie-back line at the pump exhaust connection. On closed loop systems, care should be exercised to assure that the pump is isolated (motive supply, condensate inlet and discharge, and exhaust/tie-back line all closed) and that case pressure is relieved prior to breaking this connection to avoid injury to personnel. Also, under fault conditions, it is possible that hot condensate may run out of the exhaust connection when broken for both closed loop and vented systems. This possibility should be taken into consideration when performing these steps to avoid scalding of personnel or water damage to nearby equipment. Cause d) Motive inlet valve leaking and/or worn. e) Mechanism Faults i) Broken springs ii) Ruptured float iii) Mechanism binding f) Exhaust/tie-back causing vapor lock (vented or closed loop). g) Inlet check valve stuck closed. 4.Chattering or banging in return main after pump discharges. 5.Vent line discharging excessive flash steam (vented applications only). 9 4.a) Vacuum created at pump outlet after discharge because of acceleration/deceleration of large water slug in return main (usually results from long horizontal run with multiple rises and drops). b) Pump “blow-by”. Check and Cure d) Slowly open motive supply line, leaving the condensate inlet and discharge lines closed. Observe the exhaust connection for steam or air leakage. If leakage is observed, an inlet valve problem is indicated. Isolate pump, remove cover and mechanism assembly and visually inspect. Replace inlet valve and seat assembly. e) With motive line open, slowly open condensate inlet line to the pump, allowing pump to fill and observe exhaust connection. Keep personnel clear of exhaust! If condensate runs out exhaust connection, a mechanism fault is clearly indicated. Isolate pump by shutting off motive supply and condensate inlet, remove cover and mechanism assembly, and visually inspect. Examine springs and float for obvious defects. Stroke mechanism and check for any source of binding or increased friction. Repair and/ or replace all defects observed. f) If mechanism is heard to trip and no fluid is observed running out the exhaust connection, slowly open the discharge line from the pump and observe operation. Keep personnel clear of exhaust connection! If pump cycles normally, a fault in the exhaust/tie-back line is suspected. Recheck the exhaust/tie-back piping layout for compliance with the installation instructions. Exhaust/tie-back line must be self-draining to prevent vapor locking the pump. g) If mechanism is not heard to trip and fluid is not observed running from the exhaust connection, it is suspected that the fault lies in the condensate inlet piping. Assure that all valves leading to the pump have been opened. If so, this indicates that the inlet valve is stuck closed. Isolate the pump and check valve and relieve line pressure. Visually inspect the head, seat and stem. Clean seating surfaces and reinstall or replace, if necessary. Reinstall exhaust/ tie-back connection and open line. 4.a) Install a vacuum breaker at the top of the lift (at high point in return line). For pressurized return systems and air eliminator may be required downstream of the vacuum breaker. (See Fig. 8). b) Check condensate inlet pressure and static backpressure at the pump discharge. If the inlet pressure equals or exceeds the static backpressure, a “blow through” problem is suspected. On vented systems, check for leaking traps discharging into the condensate inlet line which would increase inlet line pressure. Replace any faulty traps. On closed loop systems, if condensate inlet pressure can exceed static backpressure under normal operation (i.e. boost in equipment operating pressure via a modulating control valve or significant decrease in static return main pressure), a pump trap combination is required. The pump trap combination will prevent passage of steam into the return main and allow the pump to cycle normally when condensate is present (See Fig. 4) 5.a) Faulty steam traps discharging live 5.a) Check for leaking traps discharging into condensate return. Repair or replace faulty traps. (See also 4(b), steam into condensate inlet line Pump “Blow-By”). (See also 4(b), Pump “Blow-By”). b) Excessive (over 50 lb/hr) flash b) Vent receiver ahead of pump. steam being vented through pump. c) Exhaust valve stuck or worn. c) Isolate pump and remove cover and mechanism assembly. Remove exhaust head and seat assembly. Visually inspect seating surface. Clean and reinstall or replace, if worn. Other Typical Hook-up Sketches FloatOperated Air Vent Reservoir Figure 8 Pressure Powered Pump Discharging to Long Delivery Line (Air Eliminator needed with seal in piping) The hook-up sketches shown do not necessarily represent recommended arrangements for specific service conditions; but rather serve only to illustrate the variety of applications where the pressure-powered pump can be utilized. Design requirements for each application should be evaluated for the best condensate recovery arrangement tailored to your specific needs. For use of the pressure powered pump in hook-ups other than those described previously, and for any additional information you may require, contact Spirax Sarco Applications Engineering Department, toll free: 1-800-833-3246 Non-Electric Pressure Powered Pump †H - Total lift or back pressure is the height (H) in feet x 0.433 plus PSIG in return line, plus downstream piping friction presure drop in PSI calculated at a flow rate of the lesser of the 6 times the actual condensate flowrate. LP Flash Steam Exhaust Steam Vented to LP System Total Lift †H Flash Recovery Vessel HP Condensate & Flash Steam Thermo-Dynamic Steam Trap Figure 9 Wye Strainer Condensate Wye Strainer Non-Electric Pressure Powered Pump Figure 10 Non-Electric Pressure Powered Pump Wye Strainer Thermo-Dynamic Steam Trap Flash Steam Recovery at Pressure Above or Below Atmospheric Pressure Powered Pump Draining Water from Sump Pit Back Pressure Great Than LP Flash Pressure 15” Swing Check Wye Strainer Steam Supply 1” Equalizer Line Return Main Vacuum Space Vacuum Breaker Air Vent Self Acting Temperature Control Flow Arrangement of Small Steam/ Liquid Heat Exchanger where steam space pressure may fall below back presure. Temperature Control Sensor Steam Supply Heater Total Lift H P Filling Head Alternate Discharge Connection Return Wye Strainer Centrifugal Pump Wye Strainer ThermoDynamic Steam Trap Pipe to Drain Non-Electric Pressure Powered Pump Head “H” must be enough to give trap capacity needed when steam space pressure falls to zero. Pipe to Drain Figure 11 - Draining Condensate from Vacuum Space to Return Main 10 Figure 12 Draining Small Heat Exchanger and Other Loads to Pressure Powered Pump Spira-tec Steam Trap Loss Detector Vent Float & Thermostatic Steam Trap Multiple Loads Connected to Vented Receiver Non-Electric Pressure Powered Pump Spirax Sarco Applications Engineering Department Toll Free at: 1-800-575-0394 SPIRAX SARCO, INC. • 1150 NORTHPOINT BLVD. • BLYTHEWOOD, SC 29016 PHONE 803-714-2000 • FAX 803-714-2200 11
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