HEAT TRANSFER STORAGE CALORIFIERS EC SERIES SC SERIES BT SERIES

Transcription

1 STORAGE CALORIFIERS EC SERIES SC SERIES BT SERIES

2 INTRODUCTION The HRSFUNKE Storage Calorifiers offer a high quality solution for domestic hot water (DHW) heating. The standard range is manufactured from either stainless steel, copper, copper lined steel, galvanised steel or glass lined steel. The heater battery is manufactured from either copper or AISI 316L stainless steel AISI 316L with the electrical heaters made from from Nicalloy 825 ensuring an hygienic, reliable long life. The heaters are removable for cleaning and inspection purposes. These storage calorifiers are also designed to be used with electricity as the primary heat input. This is ideal for applications where there are no boilers or other water generating equipment available. Although electricity is associated with high running costs, it is also a very efficient means of DHW heating since all of the power used is converted into heat. The use of electricity also negates the need for extra space within the plant room to cover the duty, so boilers can be smaller, thus freeing up space for other applications. Of a high quality design and manufacture, the HRSFUNKE Storage Calorifiers offer an excellent product both aesthetically and technically. The units are bespoke, and can therefore be designed around constraints within the plant room, with special attention being paid to where the terminating connections need to be on the unit to ensure that they match up with existing pipework. This helps to reduce on site costs due to labour and material savings. WHY HRSFUNKE? HRSFUNKE has many years experience in the design and manufacturing of storage calorifiers. By using only the highest quality materials and components, we can guarantee the long life of our calorifiers removing the inconvenience of unit failure. DESIGN AND MANUFACTURING STANDARDS All our calorifiers are manufactured in accordance with the European Pressure Equipment Directive 97/23/EC. The standard units fall within the Group 2 Liquids category, Chart 4, thereby having a PED Category of SEP (full details are available from our technical office). All wiring and electrical assemblies conform to the latest IEE regulations. The design and manufacture of Calorifiers is generally carried out in accordance with BS Part 1 Grade A. However, where the scope of BS853 Part 1 is deemed insufficient or specified site requirements need a higher specification and design manufacturing code, calorifiers are manufactured in accordance with BS853 Part 2 with PD5500:2009 being offered as an alternative design code. Other design standards are also available should it be required. STORAGE VOLUME AND RECOVERY PERIOD The storage volume of the cylinder (capacity) and THE recovery period (heat up period) determine the primary power input required (kw) and therefore the output (litres/hour). The recovery period is the time it takes to heat the water up from cold (usually 10 C to 25 C) to the working temperature (usually 60 C to 65 C) in minutes or hours. Long recovery times require low primary power input whereas short recovery times require high primary power input. The actual storage volume requirements can be roughly calculated using the table below which should give good results. A study of the application should be made to determine actual requirements, taking space, weight loadings and power supply into account when selecting a volume. Type of Building Storage/Person (Litres) Recovery Period (H ) Hotel 45 2 School/College 5 3 Boarding School 25 2 Student Apartments 35 3 Houses/Apartments 45 2 Factories/Offices 5 3 Hospital Wards 30 1

3 SOLAR CHOICE STORAGE CALORIFIER CALORIFIER MATERIAL SELECTION The material specification of a calorifier is generally carried out to suit site requirements, the calorifier pressure and also the physical dimensions of the cylinder. Due to the high build specification and quality of the materials used for our calorifiers they are guaranteed to last a lot longer than those manufactured from inferior materials, which are susceptible to corrosion. COPPER Copper is virtually impervious to attack by corrosive or aggressive water. It is a popular material choice used throughout the world due to its durability and long life. Shells manufactured from copper gain a coating of copper oxide on the surface, which protects against corrosion. Where water is aggressive, an aluminium anode can be fitted into the shell, this then deposits an aluminium film onto the surface, which permanently protects the shell from corrosion. The anode does not need replacing throughout the life of the calorifier. Please note that copper shells should not be used in conjunction with galvanised steel pipe work or fittings due to the incompatibility of the two materials. GALVANISED STEEL Galvanised steel shells are also available. The shells are manufactured from carbon steel and then hot dipped in a galvanising tank. This deposits a layer of zinc onto the surface. Galvanised shells offer excellent corrosion protection in hard water areas, but should not be used in soft water areas. Soft water prevents the protective layer forming on the surface of the shell. Magnesium anodes should be fitted to galvanised cylinders to give the shell a protective coating. Anodes should be replaced annually to ensure the long life of the calorifier. Copper pipe work or fittings should not be used in conjunction with galvanised shells. COPPER LINED STEEL Due to low material design strengths, solid copper may become uneconomical to use on cylinders with larger diameters and high pressures. For where a copper shell is impractical we offer a copper lined steel shell calorifier. This material option combines the high strength of carbon steel with the corrosion resistant properties of copper. The process involves manufacturing a carbon steel outer shell and then lining it with copper sheets that are welded together to form a waterproof surface. All wetted parts within the calorifier are manufactured from copper. Anti vacuum valves are fitted as standard to copper lined cylinders to avoid the vessel collapsing under vacuum conditions when draining down without a suitable vent. STAINLESS STEEL Stainless steel calorifiers are becoming more popular for DHW heating due to its high material strength and compatibility with potable water. However, calorifiers with stainless steel shells may be unsuitable for installation in systems with a high chloride content since the chloride can attack the welds. GLASS LINED STEEL The shell is manufactured from carbon steel and then internally lined with glass or enamel. The lining is hygienic and resistant to corrosion and scale formation. These are supplied with a magnesium anode to provide additional cathodic protection. These can be easily checked and replaced.

4 SELECTION AND SIZING OF CALORIFIER STORAGE SIZE AND HEATING LOAD We cannot make an exact calculation of hot water consumption in a public area since the demand will fluctuate throughout the day. It is therefore better to collect all the data available and calculate the peak load demand. Alternatively, we can make a general calculation based on the hot water requirement per person and the recovery period required. In general calculations are made based on heating the water from 20 C to 65 C. If the required temperature is below 65 C either the hot water demand has to increase or the heating load should decrease. FLOW RATE Flow rate will depend on the demand for hot water. It will be optimum during peak demand. Heating load should be calculated to satisfy the maximum flow rate. SAMPLE HEATING LOAD CALCULATION For a Hotel: Normal recovery time is two hours General hot water demand = 45 Litres/Person Maximum demand = 125 x 45 = 5625 Acceptable peak Demand = 0.7 x 5625 = 3940 Max. Flow rate required = 3940L / 2HRS = 0.55 L/S Heating Duty Required = 0.55 x 4.2 x 45 = 104 kw So a Calorifier with a capacity of 4000 L with a 105 kw duty heater will be sufficient for this application. The specified system can supply the maximum flow rate based on the peak demand. Capacity Litres Dia mm H.O/E mm Max Ht. Access size C D E DN /2 " B SP 3 /4" B SP 1.1 /2 " B SP HRSFUNKE standard models. custom models are also available C on n ect i on s F G H J 1/2" B SP 3/8" B SP 3/4" B SP 3 /4 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN " B SP 1 " B SP 2 " B SP 1 /2 " B SP 3/8 " B SP 1 " B SP 1 " B SP DN 450 DN 65 PN /2" B SP DN 65 PN 16 1 /2 " B SP 3/8 " B SP 1.1 /2" B SP 1.1 /2" B SP DN 450 DN 65 PN /2" B SP DN 65 PN 16 1 /2 " B SP 3/8 " B SP 1.1 /2" B SP 1.1 /2 " B SP DN 450 DN 80 PN 16 2 " B SP DN 80 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 80 PN 16 2 " B SP DN 80 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 100P N 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP DN 450 DN 10 0 PN 16 2 " B SP DN 10 0 PN 16 1 /2 " B SP 3/8 " B SP 2 " B SP 2 " B SP

5 Key A. Primary Inlet B. Primary Outlet C. Hot Water Outlet D. Secondary Return E. Cold Feed F. Thermometer G. Pressure Gauge H. Safety Valve J. Drain K. Thermostats (1 BSP) L. Inspection Opening M. Immersion Heater N. Anti-Vacuum Valve A,B,K H G C F D,E ØX The Standard HRSFUNKE range Calorifiers have working pressure of 6 BarG and 10 BarG. Higher pressures are also available. H G L C F 100 D K M L Y A B E J X150- Vertical Models 75 Y C H G F A B K M D J E

6 IMMERSION HEATERS FIXED ROD ELEMENTS The rod element is made up of a resistance heating coil surrounded by compacted magnesium oxide powder enclosed in a tubular metal sheath. The element is brazed to the heater boss or flange. If an element fails the entire heater must be replaced. These heaters are generically screwed BSP. Our standard element material is Nicalloy 825. This is a high alloy stainless steel and has excellent corrosion resisting properties. Generally this material can be used in hard and aggressive waters and, in a range of chemical solutions. GLANDED ROD ELEMENTS The rod element comprises a resistance heating coil surrounded by compacted magnesium oxide powder enclosed in a tubular metal sheath. The rod element is brazed to glands that are bolted to the element flange. If an element fails the individual element can be replaced, however, the vessel must be drained and the heater removed. REMOVABLE CORE ELEMENTS A removable core element made up of resistance wire wound inside ceramic formers. Removable core elements are inserted into element tubes, which are expanded, brazed or welded onto the heater flange. If an element fails the individual element can be replaced without draining or removing the heater from the vessel. Removable core elements operate at a much lower watts density than rod elements and have much heavier wall thicknesses so they can operate in a far wider range of conditions. Our standard sheath material is copper, which is generally suitable for use in hard and aggressive water conditions, particularly water with a high concentration of chlorine, for example desalinated water. ELEMENT WATTS DENSITY Element watts density is defined as the amount of watts given out per unit surface area of an element. A high element watts density reduces the life of an element and significantly increases the effect of corrosion on the element sheath. High element watts density causes water to boil around the element and produces a noise similar to that of a boiling kettle. Where an immersion heater has been fitted close to sleeping accommodation it has been known for this noise to keep people awake at night. Due to their design, removable core elements work at a low watts density, which allows them to operate with significantly less corrosion problems than rod elements. Generally removable core element watts density is below 3.1W/cm 2 (20 W/in 2 ) With the exception of domestic and some light industrial heaters the standard watts density for rod element heaters is 9.3W/cm 2 (60W/in 2 ). The standard watts density on our flanged heaters is 7.4 W/cm 2. This is suitable for heating most types of water. Where water conditions are very hard or aggressive particularly in respect of desalinated water or where chemical solutions are being heated, please contact our technical department to obtain the correct element specification.

7 CONTROL PANEL The control panels are bespoke, specific to each project and are designed and manufactured with the highest quality components. The panels can be supplied with either temperature based, timed or thyristor control as standard. The panels are wired through a low water switch in the tank to ensure the heaters are not running dry. Typical Electrical Specification Isolator with compatible door interlocking handle. Relays are Finder Fl or equivalent. Enclosure for the control panel is made from sheet steel with an IP rating of IP69X and is at least IP54 once assembled. MCB D type triple pole CE marked and independently ested and approved to EN60947 and EN60898 with a breaking capacity of 10 KA. 2A C type single pole MCB for control supply CE marked and independently tested and approved to EN60947 and EN60898 with a breaking capacity of 10KA. Cable terminals are 10mm rated at A for power. Cable terminals are 2.5mm rated at 24A for control. Cable terminals are 2.5mm rated at 24A for BMS signals. Pilot lamps are 230Vac LED bezel style 22mm with IP rated seal. Available in various colour options. Contactor details as per data sheet. Typical Control Philosophy Panel is to operate in multi stages through an independent timer control per stage. Once there is a demand for heat from the control thermostat within the immersion heater the first stage contactor will be energised to give power to the first stage. If the heat has not been satisfied after the given time the timer will bring in stage two. This continues until heat has been satisfied through timers two and three until all stages are energised and/or until heat has been satisfied. The low temperature relay will be controlled via a separate thermostat. This is to provide indication that the vessel is under temperature only. The low level switch will stop the immersion heaters from operating until the tank is sufficiently filled with water. Control Panel Typical Timed Control Type The high temperature thermostat has a built in manual reset facility that will require manual intervention to reset.

8 HEATER BATTERY U-tubes are the most common heat exchangers used in calorifier manufacturing. Our U-tubes are made with high efficiency tubes, which are unaffected by thermal expansion to provide optimum levels of reliability. The tubes in the heater batteries are available in plain copper, making them suitable for both hard and soft water areas. Standard batteries are manufactured using copper integron tubes. The heater battery is also available in stainless steel AISI 316L offering an hygienic, reliable long life. The heater is removable for cleaning and inspection purposes. Enough space must be allowed to permit removal of the batteries. If the required space is not known, assume the distance to be equal to the diameter of the vessel. The standard range of battery duties are based on a one hour recovery period raising water from 10 C to 60 C with a primary medium of water at 82 C to 71ºC. Bespoke calorifier designs are available along with other duties, working pressures and primary mediums. Please contact our sales department for further details. Instead of U-tube, spiral tube heat exchanger designs are also available, which offer an alternative cost effective solution. Primary Side Flow Rate Requirement Heating load 100 kw. As per standard primary side temperatures: Inlet = 82 0 C Outlet = 71 0 C Heating Duty = 100 kw Flow rate = 100/(4.2 x 11) The selected 'U'-tube will be capable to produce 100 kw heating duty if there is a primary flow of 2.17 L/s Heading Duty Heat Transfer Area kw m 2 mm mm mm mm Based on HRSFUNKE standard, subject to change Inlet Size Outlet Size Flange Size Length

9 HRSFUNKE Storage Calorifiers are suitable for both vented and unvented (pressurised) systems. HRSFUNKE offer calorifiers suitable for both types of systems together with equipment to ensure correct operation. VENTED SYSTEMS The calorifiers can either be vented from the secondary flow connection or from a dedicated vent connection to allow air to exit the calorifier, air to enter the calorifier during drain down, and also thermal expansion of the water when it is heating up. The vent connection or pipe should never be blocked or valved off. The exception being to vent/bypass valves on multi-calorifier installations. UNVENTED SYSTEMS Unvented systems also known as sealed or pressurised systems are more common in installations than vented systems due to building regulations. They are also used when it is not practical to fit a vent. For unvented systems additional equipment is required: The shell should be designed at a pressure calculated after thermal expansion of the cold water. Pressure/temperature safety valves should be fitted in case of control failure. An expansion vessel should be fitted to accommodate the thermal expansion. A cold feed kit comprising isolating valves, strainer and pressure reducing/regulating valves and check valves should be fitted to regulate the cold feed pressure and to stop backflow from the calorifier into the cold water system. A booster set may have a pressure reducing valve fitted as standard on fixed speed pump units. DIFFERENT MODEL HRSFUNKE CALORIFIERS HRSFUNKE calorifiers are available in a range of models dependent on the application. Options include electric calorifiers with electric heaters, single duty calorifiers with U-tube heat exchangers with either boiler or solar systems as the heating source and double duty calorifiers with electric back up heaters. Electrical Calorifiers - (EC Series) Storage Calorifier - SC Series Buffer Tank - (BT Series) Type: EC Series S torage Volume: 5000L Heating Duty: 135 kw Type of Material: SS Type: SC Series Storage Volume: 5000L Primary Heating Duty: 140 kw Back up Duty: 60 kw Type of Material: CL Type: B T Series S torage Volume: Type of Material: GL 5000L Ex: EC/5000/135 - SS Ex: DDC/5000/120/40 SC/5000/140/60 - CL Ex: ST/ GL

10 ACCESSORIES Thermometer The thermometer measures the temperature inside the tank and is located near to the top to obtain the temperature of water reaching the outlet to get the secondary side flow temperature. Supports Our calorifiers are supplied with permanent legs/supports fixed to the shell. Manhole Manholes are supplied to allow for internal inspection of the tank and heater. The heater can be inspected by removing it from the outside, but the manhole allows inspection without removal. The standard manholes take the form of a flanged neck piece extending away from the calorifier body. Anodes Anodes can be provided based on the shell material or as per requirement. Normally anodes are supplied with glass lined calorifiers to protect the shell from corrosion. Magnesium anodes are normally specified and the life time of the anode will depend on the quality of water and should be removed and replaced at regular intervals. High Limit Cut Out Electric calorifiers are fitted with a high limit cut out to monitor overheating and a manual reset button to restore to original condition after malfunctioning. Low Level Switch All Electric calorifiers should be fitted with a low level switch above the heater to ensure that it is not running in dry conditions, which can damage it. Pressure Gauge Safety Valve All hot water application tanks should be fitted with a safety valve to protect the calorifier against the occurance of high pressure due to control malfunction or incorrect operation. We are able to supply a combined pressure/temperature relief valve for total protection. Insulation The calorifier shell requires thermal insulation to prevent unnecessary heat loss. The calorifier may be standing for hours with hot water and if the tank is inadequately insulated the stored water will cool down. Our tanks are supplied with compressed 50mm thick CFC free polyurethane or mineral wool insulation encased in stucco aluminium cladding. Anti-Vacuum Valve All copper lined calorifiers must be protected against partial vacuum and ours are fitted with an anti vacuum valve. This should only be removed during inspection Control Thermostat In electric calorifiers the control of the heating depends on the feedback from the control thermostat so the accuracy of control depends on the selection of control thermostat. In our electric calorifiers the control is either by a number of control switches located at different levels or by a single temperature switch which activates the heating process and is continued by timer control relay in different steps. Expansion Vessel Expansion vessels are used with closed hot water and DHW systems to absorb the excess water pressure caused by thermal expansion. The expansion vessel is a small tank, which is separated into two parts by a rubber diaphragm. One part is connected to the hot water line and contains water. The other part is the dry side and contains dry air or other gases under pressure. During typical operation with normal pressure the diaphragm will push against the water inlet, but when the line pressure is exceeded the force reverses and the diaphragm pushes against the dry side. A pressure gauge is fitted near to the top of the tank. This is used to measure the pressure inside the tank during operation to ensure that it does not exceed the designed pressure.

11 EXPANSION VESSEL Expansion vessels are used with the closed hot water system and domestic hot water systems to absorb excess water pressure caused by the thermal expansion. The expansion vessel are small tanks having two parts isolated by a rubber diaphragm. One part a whole tank which is connected to the hot water line and so will contain water. The other part is the dry side which contains dry air or other gases under pressure. During normal working conditions with normal pressure the diaphragm will push against the water inlet but when the line pressure is exceeding the force it will reverse and the diaphragm will move comprising the air on its other side.

12 HRSFUNKE TURNKEY SOLUTIONS STEAM SYSTEM HOT WATER GENERATION PLANT SOLAR WATER HEATING SYSTEM HEAT EXCHANGERS SKID PACKAGES HRSFUNKE PRODUCT OF RANGE PLATE HEAT EXCHANGERS HOT WATER BOILERS STORAGE CALORIFIERS FLAT PLATE COLLECTORS STEAM BOILERS STEAM GENERATORS PISTON PUMPS SHELL AND TUBES UNITED KINDOM (UK) SPAIN HRSFUNKE Heat Transfer Ltd Unit 15, Hanson Lane Enterprise Centre Hanson Lane, HX1 5PG, Halifax, UK Tel +44 (0) Website: HRSFUNKE Heat Transfer SL C/ Magallanes, 5 Pol. Ind. La Estrella Molina de Segura Murcia Spain Tel: (+34) (0) mail@hrsfunke.es Website: MIDDLE EAST SALES & SERVICE OFFICE HRSFUNKE Heat Transfer FZE, P.O Box: , Dubai UAE HRSFUNKE Heat Transfer LLC, P.O Box: , Abu Dhabi UAE Tel: Fax: mail@hrsfunke.com Web: