Technical Guide. Installation, Operation and Care. EP E series 7 step electric boilers 26 and 42 kw

Transcription

1 Technical Guide Installation, Operation and Care EP E series 7 step electric boilers 26 and 42 kw Arkelstorpsvägen 88, KRISTIANSTAD Tel , Telefax info@varmebaronen.se ENG THL artnr

2 EP E-series Contents: Functions... 2 Technical Details... 3 Installation, General... 4 Ambient temperature Water quality Placement of the boiler Cables and pipes Location of low current cable Safety and supply line Heating Installation... 4 Heating installation, general Flow requirements Recommended flow Pressure drop diagram Open system Closed system; <2.5 bar, <100 kw or <120 C <2.5 bar, <100 kw or <120 C Heating system with VVB Electric and oil-fired boilers in series Electrical Installation... 6 General Supply cable EP 26 E Supply cable EP 42 E Circulation pump External unit Load guard External blocking 0-10Vdc control 0-10Vdc of connected power Settings... 7 Number of power steps Circulation pump Fuse: Element Delayed Switch-on Electrical Diagram EP 26 E... 8 Electrical Diagram EP 42 E... 9 Control Electronics Control panel Starting Check after installation Start Operation & Care General Venting Overheat protection Excess temperature protection Safety valve Draining Risk for freezing Troubleshooting diagram Component specification Heating or industrial process The E series consists of a 26.2 kw and a 42 kw boiler. The boilers can be used for heating waterborne heating systems or for industrial processes. Construction The electric elements are made from stainless steel SS 2353 with a brass head. The pressure vessel is made from steel plating and is approved for 4 bar operational pressure. Connections for supply, safety and return lines and draining valve are at the rear of the boiler. Compact design Despite the compact design, 780 x 280 x 630 mm (h x w x d), there is plenty of room for electrical connections under the lid. Seven power steps The boiler s power output is divided into seven steps that are connected during temperature shortfall. The boiler temperature is adjustable at C. The temperature controls adapt the power output to the heating requirements. The power can be limited to four power steps. From a safety perspective the boiler manages zero flow, so it does not need to be equipped with a flow indicator. Functions Load guard Load guard and A transformer included. Delayed Switch-on Reconnection after power failure for more than three minutes to be carried out in accordance with the Electricity Producers norms. External control The boiler has a connection for external blocking or power control with a 0-10 Vdc signal. There is a 0-10 Vdc outlet for external display of connected power. Alarm Alarm indicator for overheat is on the front panel, there is also a connection for an external indicator. Outdoor temperature compensation There is an accessory available for outdoor temperature compensation, UTK E, for the control of supply temperature as a function of the outdoor temperature and selected heat curve. -2-

3 EP E-series EP 26 E 42 E Power kw Current A Step size kw Current/step A Connection cable, max area 16 25* mm 2 Technical Details Common data Voltage 400 3N~ V Frequency 50 Hz Cable fitting Ø 37 mm Water volume 17 litres Testing pressure 5.2 bar Operating pressure 4** bar Max temperature 120 C Operation temperature C Pipe connection R 32 external thread Dimensions height 775 mm width 280 mm depth 630 mm Weight 50 kg Cladding class IP 24 * For 5-phase cable, dismantle the clamp on the neutral terminal ** Other pressure classes available. We reserve the right to make changes in design without prior notice. Front view, cross section Side view, cross section Rear view EP 26 E 1. Supply / safety pipe R32 external thread. 2. Return pipe R32 external thread. 3. Drainage valve R Electric elements 5. Removable ceiling plate for connection space. 20. Cable bushings. 22. Adjustable bolts. Front panel EP 42 E -3-

4 Installation EP E-series Ambient temperature To avoid unnecessary wear and tear of electrical components the ambient temperature must not exceed 30 C. Water quality The boiler is designed for non-oxygenated water. For areas with hard water, it is recommended that the water be treated before the boiler and heating system is filled. Hard water causes boiler scale. To avoid corrosion damage to elements and the heating plant, the ph should be as neutral as possible. (Neutral ph = 7) High levels of chloride in the water can cause damage to the stainless elements. If it is not possible to lower the chloride level then copper elements should be used instead. Placement of the boiler The boiler is approved for floor placement in accordance with the high power regulations. Wall brackets are available. Cables and pipes When laying cables and pipes it must be possible after installation to remove the front plate and open the roof plate of the boiler for service work. Placement of low power cable Low power cables must not run parallel with high power cables because induction could affect the low power cable signal. Safety and supply line If an open expansion vessel is not connected to the safety pipe then it must be equipped with automatic venting. Air could collect at the top of the boiler vessel and cause damage to the elements. The safety valve or expansion vessel safety pipe is connected to the supply pipe. Heating Installation Heating installation, general - Installation must be carried out in accordance with the Heating & Hot Water Regulations. - The boiler is mounted horizontally with vertical pipe connections to allow trapped air to escape. Flow requirements The boiler requires a constant and sufficiently large flow to function satisfactorily. If the flow is too low the following problems can occur: - The difference between the temperature setting and actual temperature in the boiler increases. - Unsettled regulation that increases wear and tear of the boiler s relays and contacts, with reduced service life as a result. If the flow is too large the following problems can occur: - Vibrations in the elements resulting in noise and reduced service life. -Unnecessary wear and tear on the system components. Below are the min and max and recommended flow for the boilers. Recommended flow gives a t at 10 C at max power. EP 26 E: min / max: l/sec, t = 25-3 C recommended: 0.65 l/sec EP 42 E: min / max: l/sec, t = 25-5 C recommended: 1 l/sec The boilers manage zero flow for safety reasons, but to maintain good function and avoid unnecessary wear and tear on the components, the flow recommendations must be followed. The pressure drop diagram shows the fall in pressure at different flows. The higher the operating temperature and temperature precision, the higher the flow. Pressure drop diagram Pressure drop kpa Flow litre/second -4-

5 EP E-series Open system The safety pipe must be a continuous, non-closable line rising up to the expansion vessel. The pressure height must exceed the pump s lowest statistical pressure on the suction side. Heating Installation Closed system; <2.5 bar, <100 kw and <120 C The safety and venting valves are mounted on the boiler safety pipe. Electric and oil-fired boilers in series If the boiler is dimensioned to 50% of the calculated energy requirements it would manage around 80% of the total energy consumption. When the electric boiler cannot cope with the requirements, the oil-fired boiler goes in and supports or takes over the heating. When the three-way valve H turns off the heat to the heating system (right gate closed), the boiler still has circulation via the pump G. The pump I ensures flow in the heating system through the bypass valve J. With valves E the oil fired boiler can be disconnected from the system and with valves F the electric boiler can be disconnected. >2.5 bar, >100 kw and >120 C Safety valves, emergency safeguard, pressure control and venting valve are mounted on the steam header on the boiler s supply and safety pipe. Heating system with VVB The boiler heats the hot water and heating systems. The systems work independently of each other. The supply temperature to the radiator system is controlled by a three-way valve H. When the heating system does not require any heat, the three-way valve is closed (left gate), the water then only circulates around the heating system. The flow through the boiler is retained by the circulation through the hot water heater. The meaning of the symbols in the above illustration: A Electric boiler J By-pass valve B Closed expansion vessel K Supply pipe C Oil-fired boiler L Return pipe D Safety valve M Air vent E Valve N Emergency protection F Cut-off valve O Pressure control G Circulation pump internal P Open expansion vessel H Three-way valve R Double-cupped VVB I Circulation pump heating Q Steam header -5-

6 EP E-series Electrical Installation General - Electrical installation must be carried out under the supervision of a qualified installation engineer. - Installation must be in accordance with the high voltage directives. - The supply cable must be dimensioned in accordance with the high voltage directives. - A multi-polar breaker must be installed ahead of the boiler. - The water and water system must be filled and vented before the power is connected. Supply cable EP 26 E Supply cable, 5-phase, max 16 mm 2 Cu, 50 A fuse, connected to terminal in the boiler. Circulation pump Connecting the circulation pump to the boiler allows you to utilise the pump stop function and you can exercise the pump when not in use. The function can be turned off to provide continuous operation. Max 2 A. PLEASE NOTE, 230V External unit Fused socket for supply to external unit, max 2 A. PLEASE NOTE, 230V External blocking The power can be blocked by an external potential-free switch. An open switch reduces the power in steps. Existing lug is removed V control The power can be controlled by an external 0-10Vdc signal, which corresponds to 0-100% of the installed power, see below. The lug between 2 and 3 is removed Vdc GND EP 42 E The supply cable must be PEN or 5- phase of copper, max area 25 mm 2. The phase conductors are connected to a contactor, the earth to a neutral. Load guard Together with the current transformer, the load guard measures the load on the main fuses. The size of the main fuse, A, is set on the printed circuit card. The current transformers are positioned on the cables that come from the fuses to be protected, normally the main fuses. 0-10V signal of connected power The boiler s connecting power can be obtained in the form of a 0-10Vdc signal, which corresponds to 0-100% of the installed power, see below V GND The supply cable must be high voltage insulated, with a minimum area of 0.75 mm 2. Common conductor connected to terminal Installed power Selected number of steps corresponds to installed power. Example: The boiler is set so that the element only uses five output steps, 10.5 kw is then the installed power. At voltage control, 0-10Vdc, 10V is needed for all the five steps to work. The same concerns the voltage signal for the installed power. -6-

7 EP E-series Number of power steps If the boiler s total power output is not to be utilised it can be limited to min four steps. The number of steps corresponds to the installed power. EP 26 E: 3.8 kw/step EP 42 E: 6 kw/step Circulation pump The pump has two types of operation: 1: Continuous operation. 2: Summer operation / eco function. Means the pump stops eight hours after a power step was last connected. The pump is exercised every twelfth hour. The best function is attained when the boiler is controlled by an outdoor temperature compensator, UTK E. Settings Fuse: The load guard requires information about the size of the main fuse. This adjustment is only necessary if the load guard is to be used. Element The load guard requires information about the size of steps in kw. This parameter is preset at the factory and must not be changed. EP 26 E: 3.8 kw EP 42 E: 6 kw Delayed Switch-on According to the Swedish Association of Electricity Producers, only 50% of power output should be connected immediately, the rest must be delayed by one hour. This means that after a power failure longer than three minutes only three of the boiler s power steps are connected directly, the rest are connected in steps, if required, an hour after the power has returned. To test the boiler after it has been shut down for installation or service, the delayed Switch-on can be temporarily disconnected. This is done by pressing the QUICK button and keeping it pressed in until the status indicator glows with a steady light. Settings Number of power steps (1 & 2) OFF ON off on off on off off on on 4 step 5 step 6 step 7 step Circulation pump (3) Main fuse (1-3) off on eco or summer operation continuous operation EP 26 EP 42 off on off on off on off on off off on on off off on on off off off off on on on on 35 A 50 A 63 A 80 A 100 A 125 A 125 A 125 A Element / Step size (4-6) These values must not be changed EP 26 EP 42 off on off on off on off on off off on on off off on on off off off off on on on on 1,0 kw 1,4 kw 1,9 kw 2,1 kw 2,3 kw 3,0 kw 3,8 kw 6,0 kw Delayed Switch-on (7 & 8) off on off on off off on on 0h 1h 2h 2h Supply settings are in bold text. -7-

8 EP E-series Electrical Diagram EP 26 E Power Power group 1 11 Power group 2 Power group Alarm Power group one, 3,75 kw Power group two, 7,5 kw Power group three,15 kw (2 x 7,5 kw) Current transformer, common conductor connected to terminal Temperature sensor. 3. Terminal for connection of external blocking, 0-10Vdc control and 0-10Vdc out for connected power output. See electrical installation. 4. Temperature settings, set point 5. Terminal for alarm, circulation pump and voltage supply to external unit. 6A fuse. PLEASE NOTE, 230V 6. Connection for supply cable. 7. Printed circuit card 8. Control breaker. 9. Operating fuse, also fuses the circulation pump and socket for external unit. 10. Indicators for: Operation, lit when there is voltage supply to the boiler. Power groups 1 3, lit when these are connected. Alarm, lit when overheat protection is released. 11. Alarm relay, stops at released excess temperature protection. 12. Overheat protection for power groups one and two. 13. Overheat protection for power group Contactors for power group Electric element for power group one, 3.75 kw. 16. Electric element for power group two, 7.5 kw. 17. Electric element for power group three, 2 x 7.5 kw 18. Plunger tube. -8-

9 EP E-series Electrical Diagram EP 42 E Power group 3 12 Power 13 Power group Alarm 21 Power group Power group one, 6 kw Power group two, 12 kw Power group three,24 kw (2 x12 kw) Current transformer, common conductor connected to terminal Temperature sensor. 3. Terminal for connecting external blocking, 0-10Vdc control and 0-10Vdc out for connected power. See electrical installation. 4. Temperature settings, set point 5. Terminal for alarm, circulation pump and voltage supply to external unit. PLEASE NOTE, 230V 6. Connection for supply phase conductors, connected to contactor No Neutral terminal. 8. Circuit board 9. Control breaker. 10. Operating fuse, also fuses the circulation pump and socket for external unit. 11. Contactors for power group three. 12. Indicator, power group three. 13. Indicator, operation lit when there is voltage supply to the boiler. 14. Indicator, power group one. 15. Indicator, alarm; lit when overheat protection is released. 16. Alarm relay. 17. Overheat protection for power groups one and two. 18. Overheat protection for half of power group three. 19. Overheat protection for half of power group three. 20. Electric element for power group one, 6 kw. 21. Indicator, power group two. 22. Contactors for power group two. 23. Electric element for power group two, 12 kw. 24. Electric element for power group three, 2 x 12 kw 25. Plunger tube. -9-

10 Control Electronics EP E-series 1 Terminal for circulation pump. The pump has two types of operation: 1: Continuous operation. 2: Summer operation / eco function. Means that the pump stops eight hours after a power step was last used. The pump is exercised every twelfth hour. Best function is achieved when an outdoor temperature compensator, UTK E, operates the boiler. Choice is made with the breaker, see item 5. 2 Terminal for power group three. 3 Terminal for power group two. 4 Terminal for power group one. 5 Breaker for setting operating parameters, see Settings 6 Status indicator. Steady glow: Normal operation. Long + a short flash: Delayed Switch-on is blocking the power steps. Long + two short flashes: Load guard, external blocking or 0-10V control limiting the power steps. Long + three short flashes: Damaged temperature sensor or excess temperature. Quick flashes: Quick running of delayed Switchon with the help of QUICK. Off: No power or the set point is lower than 15 C; can occur when a UTK E is connected. 7 Indicator for power group three. 8 Indicator for power group two. 9 Indicator for power group one. 10 QUICK button. Used for temporary disconnection of delayed Switchon and quick connection of the power steps. 11 Temperature and set point settings. Setting range C. 12 Terminal for connecting external control units. External blocking can occur via an external potential free contact or with a 0-10Vdc signal, 0-100% of installed power output, permitted number of steps. If the latter is used for regulating the temperature, the boiler s set point should be set at the highest permitted temperature for the system. External operation control, a 0-10Vdc signal, 0-100%, of installed power output obtained from the boiler. 13 Temperature sensor, placed in a plunger tube on the boiler vessel s element base. 14 Current transformers for load guard function. With the help of the current transformers, the load guard measures the load, A, on the main fuses. At overload, the boiler power is reduced The power is reconnected when the load has decreased. Temperature control Temperature control regulates the power binarily in seven steps. The connection time between the steps is decided by the temperature difference between the actual value and set point and the actual increase in temperature. When the actual temperature is within ±2 C relative set point there are no changes to the connected power. An outdoor temperature compensator, UTK E, is available, which replaces the boiler s set point with a function that allows the temperature to be decided by the outdoor temperature and the selected heat curve. UTK E provides an improved eco function and frost protection. The excess temperature function immediately breaks all connected power if the boiler temperature exceeds the set point by more than 5 C. When the 6 = Connected power group = Non-connected power group excess temperature subsides, the power is reconnected again without the need for manual resetting. There is also a function that checks that the temperature sensor is in one piece. The status indicators blink when any of these functions start. Binary control The boiler regulates the power with binary power steps, which means the various power groups are connected as in the table below. The power for the lit lamps is added up to give the total power. The first power group make up approx. 15% of the total power, the second group approx. 30% and the third approx. 55%. Power step Power group Total power (kw) EP 26 EP , , , , , ,

11 EP E-series Control panel Control panel 1. Operation indicator, lit when the boiler is working normally. 2. Control breaker. 3. Indicator for power group one, 15% of the total power. 4. Indicator for power group two, 30% of the total power. 5. Indicator for power group three, 55% of the total power. 6. Temperature and set point settings. 7. Alarm, released overheat protection. 8. Reset overheat protection, EP 42 E only, power groups one and two. 9. Reset overheat protection. EP 26 E: power groups one and two. EP 42 E: half of power group three. 10.Reset overheat protection. EP 26 E: power group three. EP 42 E: half of power group three. 11.Thermometer Starting Check after installation Check there are no tools etc. left inside the boiler s connection area. Ensure that the boiler and heating system is full of water and vented before putting into operation. Start A. A complete inspection of the electrical system is required before starting. B.Put the main breakers and operation breakers in On position. The operation indicator should now be lit and the status indicators on the circuit board should blink. C.Set the required temperature. D.Because the boiler has been without current, only three power steps will be connected. The rest are connected after an hour if so required. The delayed Switch-on is indicated by the status indicator on the circuit board. For checking the boiler s functions, the delayed Switch-on can be disconnected for installation or service. This is done by pressing the QUICK button on the circuit board and keeping it pressed down until the status indicator shines with a steady glow. E.The boiler will now step up the required number of power steps according to the binary control until the temperature coincides with the set value. To reduce step up time, the QUICK button can be kept pressed in until the required number of steps has been reached. Delayed Switch-on According to the Swedish Association of Electricity Producers norms, only 50% of power output should be connected immediately, the rest must be delayed by one hour. This means that after a power failure longer than three minutes, only three of the boiler s power steps are connected directly, the rest are connected in steps, if required, an hour after the power has returned. To test the boiler after it has been shut down for installation or service, the delayed Switch-on can be temporarily disconnected. This is done by pressing in the QUICK button and keeping it pressed in until the status indicator glows with a steady light. -11-

12 Operation & Care EP E-series General Check with the installation engineer that the plant is in full working order after installation. Ask him to show you the functions so you are quite clear about how the plant works. Check the water pressure, there could be air left in the system some time after installation so vent and check the system at least one more time. Venting To quickly remove the oxygen in the fresh water, leave the boiler in operation a few hours with a high operation temperature, C. Vent then set the normal operation temperature. Overheat protection The boiler has two respective three overheat protection that releases when the boiler temperature exceeds approx. 100 C. The protection is reset behind screws on the front panel. You can reset when the temperature is under 80 C. Excess temperature protection An excess temperature function compliments the overheat protection. The purpose of the excess temperature protection is to disconnect all power during temporary increases in temperature that could occur due to rapidly reduced water flow through the boiler during pump stop etc. All power steps are immediately disconnected. When the temperature has sunk to the set value, the power is reconnected again in steps without the need to reset. The function comes into play when the boiler temperature exceeds the set value by more than 5 C. Safety valve The safety valve, which is mounted in the heating system together with the closed expansion system, must be regularly exercised about 4 times a year in order to maintain its safety function. Draining The electric element must be turned off before draining the system to avoid damage. Risk for freezing No part of the system is to be turned off during severe cold due to risk for frost damage. Send for an installation engineer if you suspect that a part of the system is frozen. Drain the water if the system is not to be used for some time. -12-

13 EP E-series Troubleshooting diagram PLEASE NOTE. Any work demanding tools must be carried out by an authorised electrical engineer. Begin troubleshooting by checking the status indicators on the circuit board inside the boiler. See page 10, item 6. Causes concerning these indicators are not taken up here. Fault Possible cause Correction: Operation indicator off. Operation indicator on but no heat. Group fuse blown. The boiler does not step up despite the temperature in the boiler being lower than the set value of the thermostat. The boiler has no current. Main and or control breaker off. Operational fuse blown. Indicator lamp broken. Fault in the system electronics. The element is broken. The boiler is step limited. The boiler is controlled by an external 0-10V signal. The outdoor temperature compensator is connected so that the regular thermostat does not control the boiler temperature. The temperature sensor is defective Check the main fuses. Put the breakers into ON position. Delayed Switch-on stops the boiler if it has been without current for more than 3 minutes. Check the location of the short circuit, put right and then reset the fuse. Change the lamp. Change the circuit board. Break the control and working breaker and the operational fuse, then insulation test the elements. To change the element, remove the boiler s bottom front plant and insulation. Disconnect the electrical connections and unscrew the defective elements. A box spanner for removing the elements is available from Värmebaronen. When the new elements are in place, check there are no electric cables touching them. Check the setting, see page 7 Number of power steps. The boiler s set point is too low. Check the UTK E settings Check measure the temperature sensor. PLEASE NOTE. The sensor must not be connected to the circuit board during measuring. The Temperaturgivarens temperature sensor s resistans resistance C kω C kω C kω C kω 0 32, ,0 50 3,6 75 1,5 5 25,4 30 8,1 55 3,0 80 1, ,9 35 6,5 60 2,5 85 1, ,7 40 5,3 65 2,1 90 0, ,5 45 4,4 70 1,8 95 0,8 Unsettled control, the boiler steps up a number of steps only to immediately step down again. Not enough water flow through the boiler. Check that the circulation pumps and valves are in working order. The flow can be checked in the following way: - Limit the boiler to 4 steps. - Let the boiler s temperature stabilise. - Measure the temperature difference between the flow and return. - Calculate the flow through the boiler in accordance with the following formula. - Check the flow is sufficient on the pressure drop diagram. q = P t x 1,16 q = Water flow in m 3 /hour. P = The boiler s output in kw. t = Temperature difference in C =The heat-absorption quality of the water. For flow in litre per second, multiply q with 1000/

14 Component Specification EP E-series Pos. Part No. Component Both 26 E 42 E Element 3.75 kw Element 7.5 kw Element 6 kw Element 12 kw Overheat protection 100 C Control switch 2 pol Neutral terminal NPF Earth bar JS Relay 1-pol vx Contactor 100-C30, 230V Contactor 100-C43, 230V Circuit breaker 1 pol, 6A Lamp round 230V, orange, pin Lamp round 230V, red, pin Lamp round 400V, orange, pin Potentiometer OX7E Temperature sensor Circuit board OX 7E Draining valve R15 ext O-ring for element Current transformer Thermometer C EP 26 E EP 42 E -14-