Datasheet Content
[{"filename":"VDU_VMU_en.pdf","text":"VDU\nVMU\nOil burners fuel unit\n\n\n DE120/0323\n\fOil burners fuel unit\nType VDU and VMU\n\n\nDELTA fuel unit VDU and VMU are pumps for oil burners or transfer\nsystems, designed to replace DELTA units V, VD and VM with limited\nmodifications.\n\n\n\n\nDescription\nVDU fuel unit consists of a filter (1), a pumping gear (2) and a pressure\nregulator (3). VMU unit is additionally equipped with a solenoid valve\n(4).\nNozzle port is present on both sides (5).\nPressure (6) and vacuum (7) ports are present in front cover.\nVDU and VMU units are available in two-pipe or one-pipe version. Both\nversions are self priming. The pump can be converted from version to\nthe other in few steps.\nThese units are suitable for oil with a maximum biodiesel content of\n10%. With higher biodiesel percentage, “B” version with special seals is\nrecommended. These units must not be used with water or acid.\n\n\n Pump specifications\n 1,2 ÷ 12 cSt\nOil viscosity …………………………………\n If fuel viscosity is lower than 2.5cSt (i.e. Kerosene), pressure must be lower than 12 bar.\nOil temperature …………………………….. 60°C max.\nSuction line vacuum ………………………. 0,5 bar max\nSuction line pressure ……………….…….. 2 bar max\nReturn line pressure ………………………. 2 bar max\nRotation speed ……………………….……. 3500 rpm max\nStandard strainer…………………………… Nylon mesh 150µ, V..1 with 9cm², V..2 ÷ V..5 with 20cm²\n Hub Ø32, shaft Ø8\nDimensions (EN 225) …..………………….\n (optional: hub Ø54 with adapting ring or flanged connection with holes Ø10x92)\nConnections (ISO 228/1) …………..……... Inlet – Return: G1/4”\n Nozzle (2x) / pressure / vacuum ports: G1/8”\nWeight ……………………………………….. gr. 1100\n\n\n\n Valve specifications\nPower absorbed ...…………………………. 9W\nVoltage tolerance ..………………………… -15% / +10%\nEnvironment temperature ………………... 0°C / 60°C\nWorking pressure …………..……………... 25 bar max.\nFlow factor (VDI/VDE 2173) ..…………….. 0,059 m3/h\nCut-off pressure ………………..………….. 2 bar\nStandards …………………………………… EN ISO 23553-1\nCoil specifications ………………………… Type NF84 (coil with connector plug) - Voltage available:\n 230V 50-60Hz, 110V 50-60Hz, 24V 50-60Hz, 24V DC, 12V DC\n Cable to be ordered separately, length 700mm\n\n\n\n\n2 DE120/0323\n\f Nozzle capacity Power consumption\n\n\n\n\nDimensions and connections\n\n\n\n\n H\n Model\n\n V..1 47\n V..2\n V..3 55\n V..4\n VDU5 57\nNote:\nAdapting ring Ø54/32 or flange with holes Ø10x92 has to be ordered separately.\n\n\n\n\n3 DE120/0323\n\fModel identification\n\n VMU 3 R 2 4 FA\nPump type\nVDU gear pump for oil burner\nVMU gear pump for oil burner with solenoid valve\n\nB prefix for biodiesel version\n\nNozzle capacity @10bar (*)\n1 = 27 Lt/h\n2 = 45 Lt/h\n3 = 70 Lt/h\n4 = 90 Lt/h\n5 = 105 Lt/h (only for VDU type)\n\nRotation (seen from shaft end)\nR = clockwise\nL = counter clockwise\n\nPipe Version\n1 = one pipe\n2 = two pipes\n\nPressure ranges Factory setting\n3 = 2 ÷ 7 bar 4 ±0,3 bar\n4 = 6 ÷ 18 bar (standard) 10 ±0,5 bar\n\nVoltage of solenoid valve – only for VMU type\nFA = 230 VAC FC1 = 24 VDC\nFB = 110 VAC FD = 12 VDC\nFC = 24 VAC\n\n(*) Reference value, see paragraph above for details.\n\n\n\nInstallation\n\nCAUTION: before servicing any part of the system, turn off all power and shut off oil at manual valve.\n\n1- Check that pump model complies with features of your system. If necessary, pump can be converted from one-pipe to two\npipe version and vice versa, see paragraph below for this purpose.\n2- Use the correct joint between motor and pump.\n3- Insert the pump hub in the motor housing.\n4- Screw the radial blocking screws progressively, taking care of not forcing the pump shaft along its axis or laterally to avoid\nexcessive wear on the joint and noise.\n5- Pay attention to solenoid valve: do not use it as lever.\n6- Connect pipes, paying attention that:\n - an external filter should always be installed in the suction line upstream of the fuel unit (pump filter is not meant to be a\n main filter so it can get clogged in short time if main upstream filter is absent);\n - pipes should not contain air pockets. The number of junctions should be as minimum as possible and rapid attachment\n joint should be avoided;\n - use O-Rings or mechanical seal (copper or aluminium gaskets) junctions if possible;\n - avoid overtightening: G1/8\" → 15 Nm max;\n G1/4\" → 20 Nm max;\n - do not use PTFE tape on the suction and nozzle pipes. Particles of PTFE could deposit on filter or in nozzle, reducing\n efficiency;\n - when junction threads, elbow joints and couplings are sealed with glue, avoid excessive quantities, which could enter in\n the pump and damage it;\n4 DE120/0323\n\f7- Make sure the combustion chamber is free of oil or oil vapor before operating the system.\n8- On initial commissioning, if there is a long suction line to bleed, inject some lubrication oil into the vacuum port before\n turning on the motor.\n9- After filling the tank, wait some hours before switching the burner on, so that impurities will deposit and pump will not suck\n them. Do not add additives to fuel to avoid formation of compounds which may block the pump.\n10- After turning the motor on, set the correct nozzle pressure as described in paragraph below.\n11- If necessary, vacuum test and nozzle cut-off tests can be performed.\n\n\nNozzle Pressure Setting\nMost nozzles ratings are based upon 100psig (7bar) oil pressure. The flow rate at the desired nozzle pressure must be\nestimated using the nozzle manufacturers data sheets.\nTo ensure that oil is delivered to the burner nozzle at the desired pressure, proceed as follows:\n1- with motor turned off, remove the 1/8\" plug from the port marked \"P\" and connect a pressure gauge to this port (use a gauge\n 0 - 20bar or higher).\n2- Start the burner motor, energize the solenoid valve and vent all air from the fuel unit.\n3- Check the nozzle pressure of the fuel unit and, using a 4 mm Allen wrench, adjust the nozzle pressure at desired level:\n turning the adjusting screw counter-clockwise to lower and clockwise to increase the nozzle pressure.\nCAUTION: during this setting, fuel is sprayed, if combustion is absent, a potentially explosive atmosphere is present. Pay\n attention not to ignite this atmosphere: evacuate it as soon as possible.\n\n\nVacuum Test\nVacuum test is useful to verify fuel unit suction ability, to evaluate the leak tight integrity of the entire suction line piping and to\nconfirm that the system vacuum is within the allowable specification limits of the unit.\nTo perform the test, proceed as follows:\n1- Remove the 1/8\" plug from the port marked \"V\" and connect a vacuum gauge to this port.\n2- Start the burner motor and vent all air from the fuel unit and connected suction line system.\n3- With the burner motor running, close the manual valve connected to the inlet port: vacuum measured by the gauge will\n increase. Allow the burner motor to continue to run until the highest vacuum reading is achieved. A fully primed fuel unit in\n good condition should be capable of pulling at least -0.7bar. If not, before condemning the fuel unit, be sure that all\n connections and plugs are tight, the cover gasket and the manual valve are in good conditions.\n4- With VMU type de-energize the solenoid valve and shut off the burner motor. Initially, the vacuum reading will drop and then\n stabilize within a second or two. Once the vacuum reading stabilizes, record the reading. If the fuel unit is free of leaks, this\n reading should hold constant for at least 2 minutes. If the vacuum reading drops, there is a leak that must be detected and\n fixed.\n5- When each leakage is fixed and the valve onto suction line is open, check to be sure that the current operating vacuum does\n not exceed -0.5bar.\n\n\n\nNozzle Cut-Off Test (VMU type only)\nFuel oil is not compressible but air is. Air trapped in the nozzle line will compress during burner operation; after burner\nshutdown, trapped compressed air will expand forcing an oil flow through the nozzle that will appear as incorrect Cut-Off of\nthe unit. This occurrence is particularly common with low flow rate nozzles and long nozzle pipe.\nTo verify good nozzle Cut-Off after burner shutdown, proceed as follows:\n1- Remove the nozzle line from fuel unit and connect a 1/8\" pressure gauge to the nozzle port (a gauge of 20bar or higher\nhas to be used). It may be more convenient to use a gauge fitted out with an extension nipple or with a line and flare nut to\nconnect directly to the fitting installed into the nozzle port. If any type of extension is used between the nozzle port and the\ngauge, it should be kept as short as possible to minimize the amount of trapped air.\n2- Start the burner motor, energize the solenoid valve and vent all air from the fuel unit and connected suction line system.\n3- Shut off the burner motor. Initially the pressure will drop and then stabilize within some seconds. The pressure reading on\nthe gauge should stabilize at 2 bar or higher and hold for at least two minutes. If pressure fall under 2 bar, probably shut-off\nvalve is dirty: remove the coil and unscrew the stem to clean the rubber seal. When reassembling the valve, pay attention to\nassemble all parts correctly. It is possible to replace the mechanical parts of solenoid valve.\nCAUTION: the VDU type does not perform any cut-off action. An external solenoid valve must be installed in the nozzle line.\n5 DE120/0323\n\fMaintenance\nIf pump has not worked for several months, it can be blocked: remove it from the motor and try to turn manually the shaft\n(pay attention not to damage the shaft with improper tool). Then reassemble pump and motor.\nAt least once a year pump filter has to be cleaned: remove the cover, remove the round filter and clean it with compressed\nair. Reassemble filter around the gear, pay attention that supporting legs are leaned against pump body. If the gasket\nbetween cover and pump…
