PANDORA VS UNVENTED A comparison of Pandora Heat Bank Thermal Stores to Unvented Hot Water Cylinders HIGHER PRESSURES AND FLOW RATES UNVENTED: limited in the pressure they can supply to taps by a pressure reducing valve, typically in the region of only 2 bar. PANDORA: pressures up to 9 bar to hot taps, mains providing. NO DISCHARGE PIPES UNVENTED: require a discharge pipe and tundish to protect against overpressurisation of the store. Common for discharge to spill over tundish onto floor. PANDORA: requires none. NO SPECIAL TRAINING UNVENTED: require a person to posses an industry recognised qualification to install or service. PANDORA: requires none, and can even be DIY installed. NO NEED TO NOTIFY BUILDING INSPECTOR UNVENTED: installations should be reported to, and inspected by, the building inspector, as according to the G3 building regulations for unvented, pressurised cylinders. PANDORA: requires none. NO ANNUAL MAINTENANCE UNVENTED: should be regularly serviced to check operation of safety controls. Cylinders using an internal bubble for expansion may also need this re-charged to prevent dripping discharge pipe. PANDORA: requires no regular maintenance, other than renewal of corrosion inhibitor every 5 years. NO LIME-SCALE IN STORE UNVENTED: as water is heated, limescale is deposited onto the inside walls of the cylinder, and on heating surfaces. Fresh limescale is introduced with each draw-off, and this cannot be flushed out. PANDORA: it is the same water in the store in 10 years as the day it was installed, so no limescale build-up. Plate heat exchanger is relatively immune, but can be easily flushed if needed. All the advantages, None of the disadvantages.
FAQ Some of the questions we get asked, along with the answers. What is a thermal store? If the stored water stays in the store, does that mean that the store never runs out of hot water? What are the guarantees on Heat Banks? Are there any limits on the positioning of the stores? Can I have hot water outlets above the store? How far can the cylinder be from the boiler? What do I need to check? Where is the best place to start finding out what unit to order? Do I need qualifications to install a Heat Bank? Do I need to worry about too high pressure from the mains? If the standard size of store will not fit, is there another option? Other thermal stores I have seen use coils to heat the water. Is this how a Heat Bank works? Do I need a new boiler? Can I use a Solid Fuel Boiler or Solar Panels to heat a Heat Bank? How can I ensure that I have hot water instantly available at hot taps? What are the advantages of a Heat Bank over an unvented cylinder? Does the Heat Bank boost the mains supply? What are my options if my mains is not very powerful? How can I work out the size of cylinder I need? Can the plate heat exchanger scale up? Who can I get to install the unit? Can I see a unit before I buy one? Where can I get a new set of instructions? How do prices compare to your competitors? Where can I but a Heat Bank? Do Merchants stock units? How does the system comply with the new regulations concerning overheat protection in immersion heaters and thermostatic control of hot water? Are there any disadvantages or hidden costs? How long have Heat Banks been around? What happens is something goes wrong with the unit? Q: What is a thermal store? A: In its simplest terms - a storage unit for heat. Like hot water cylinders, a thermal store saves up the energy generated by a boiler or electric heaters, allowing the householder to use this energy quickly - to run a hot tap and a shower together, for example. Without storage, such as when using a combination (combi) boiler, then it is only possibly to run one outlet at once. A thermal store differs from a hot water cylinder in that the hot water delivered to taps is heated instantaneously using the heat energy in the store. The water in the store stays in the store, and remains completely separate from the domestic water supplies. Q: If the stored water stays in the store, does that mean that the store never runs out of hot water? A: No. The entire reason for hot water storage is to store heat energy, not the actual water - that is what cold storage tanks are for. A Heat Bank will run out of heat energy and go cold in the same way that a normal hot water cylinder runs out of hot water. Heat Banks should be sized as any standard cylinder is. Q: What are the guarantees on Heat Banks? A: 1 year on site back-up (call-outs resulting from installer or user error will be charged). 2 years on components (not labour). 20 years on the store itself (provided inhibitor is refreshed every 5 years. Not including site damage).
Q: Are there any limits on the positioning of the stores? A: No. Stores can go anywhere in the property you can get the pipework to. Unlike other hot water systems they need no discharge pipe - An unvented cylinder will require a discharge to outside, and a standard cold tank / hot water cylinder system needs an overflow from the cold tank to outside. Without an external discharge, positioning and installation of the store becomes much simpler. All we would say is that if the unit is to be located in a cold loft or cellar, that all pipework is lagged, and the store preferably boxed in to cut-down heat loss, as you would with any hot water system. Q: Can I have hot water outlets above the store? A: Yes. As both your hot and cold water is supplied at full mains pressure, it is usually possible to supply outlets far above the store. This depends on you mains pressure - a pressure of 1 bar can lift water 10 metres, and likewise a pressure of 5 bar can lift water 50 metres. Q: How far can the cylinder be from the boiler? A: If there is a considerable distance (>20m), then it may be wise to use larger pipe sizes to accommodate, or to specify a higher head primary (boiler) pump. Q: What do I need to check? A: The only item that needs checking is the suitability of your mains water supply to provide both hot and cold services. Without cold storage, the mains must be capable of supplying simultaneously. Check mains water pressure, which should be generally above 2 bar for high performance. However, pressure alone is not enough, as the mains supply pipework needs to be large enough to carry the required water. The best way to test the effectiveness of the mains is to open all existing cold taps that are running off the mains to determine if there is enough water coming into the property. More below... Q: Where is the best place to start finding out what unit to order? A: Download our Panex program. This provides all standard options, but will also give you extensive help, and will generate such useful documents as wiring diagrams, and installation instructions. Once you have settles on a design (or two..) simply tell us the code (provided) and we can easily quote or discuss. Q: Do I need qualifications to install a Heat Bank? A: No. You simply need to be competent enough to perform basic plumbing and wiring. No specialist unvented qualification are required. Q: Do I need to worry about too high pressure from the mains? A: Not usually as the store can run at up to 6 bar continuous, 9 bar peak. You should however check that all your fittings (showers, washing machine hoses etc.) are suitable for your mains pressure. If you are worried then fit a pressure reducing valve set to 3.5 bar. Q: If the standard size of store will not fit, is there another option? A: Yes. We can make stores to suit (within reason). We have four different unit diameters allowing the same volume of storage in either a tall thin unit, or a short fat unit. We are also launching a range of rectangular stores (as opposed to circular) that make more efficient use of space.
Finally, it is possible to supply a horizontal store - one that lays on its side - that can be useful when there is very little head room. The standard size is however the cheapest. Q: Other thermal stores I have seen use coils to heat the water. Is this how a Heat Bank works? A: No. Coil type thermal stores use metal (typically copper) coiled tube(s) within the store, through which the domestic water flows and is heated. A Heat Bank however, circulates the water in the store (using a pump) from the top, through a plate heat exchanger, and back to the bottom of the store. The heat exchanger transfers the heat to the domestic water that also flows through the heat exchanger, while keeping the water separated. We at DPS used to manufacture coil type stores (many years back) however they were always more susceptible to limescale build up within the coils. Also, the temperature of water produced dropped gradually from the start temperature, rather than holding steady. The use of the plate heat exchanger overcomes these, and also boosts the maximum output considerably, with lower pressure losses. Q: Do I need a new boiler? A: Up to you. The standard options allow for all types of domestic boiler. A Heat Banks can even be easily connected to a combination boiler to improve performance without replacing the boiler. If you have any queries regarding boilers, it is worth checking the size of the existing boiler (if there is one). If it is a new property or there is an extension or increased water loading (more bedrooms) then you may need a larger boiler. As it is not good to vastly oversize a new boiler, some reasonably accurate idea of the heating and hot water load (pattern of use) should be obtained. We provide free software tools on this site to assist in doing calculations - Calculator.This is not a service we offer as it is time consuming and requires a knowledge of the site, but most installers, or architects should also know a thing about it. Q: Can I use a Solid Fuel Boiler or Solar Panels to heat a Heat Bank? A: Yes. We have options covering both. In fact, we have supplied stores that will connect to a gas boiler, solar panels, solid fuel stove, and geo-thermal heat source, all at the same time. Protection is included against overheating the unit (always a worry with an uncontrolled heat source) by the means of a dedicated hot water outlet (typically taken to a drain) that will relieve hot water when the store approaches overheat, and thereby prevent the temperature from further increasing. All the controls for this are factory fitted. Heat Banks are vented, so the restrictions on connecting to a pressurised storage cylinder do not apply. Q: How can I ensure that I have hot water instantly available at hot taps? A: Although the Heat Bank will generate hot water instantaneously, you may still get dead-legs in pipework - that is a length of supply pipe between the store and the tap that goes cold over time. The only way to overcome this (insulating pipes helps) is by plumbing in a secondary return circuit. In such a setup, the hot water supplies are in a loop around the property, returning to the store. A small pump can be used to keep hot water circulating around the loop keeping pipework hot. This is an factory-fitted option. Q: What are the advantages of a Heat Bank over an unvented cylinder? A: There are many important benefits, not least no discharge pipe, no trained installers and no annual maintenance - all required on unvented systems - as well as simply more water. Click here for further information... Q: Does the Heat Bank boost the mains supply? A: No. It simply heats what is already provided by the mains water pipework. This is limited by the
water pressure in your area, as well as the pipe size into the property. Both are important and should be checked. Q: What are my options if my mains is not very powerful? A: First thing is carefully check all valves, stopcocks on the supply are open (a long shot). It is always worth contacting your water supplier to see if they can up the pressure into the property. Sometimes, nearly always in flats, there are pressure limiting valves, that can be increased in setting. Maybe ask a plumber you know if he can see anything obvious - never go to an unknown (not IOP registered for example) person asking to spot problems in your house - they may magically appear. Failing these, it may be necessary to increase the pipe size of the mains coming into and within the property. Sometimes the weak point is a short link of pipework where the supply enters the house, sometimes the entire length of pipework under a driveway will need renewing in a larger size. If embarking on such a venture as digging up your drive - always talk things over closely with the water suppliers as they legally only have to provide 1 bar pressure, and 9 litres per minute (some are more co-operative than others)! If renewing the mains supply is not an option, then there are only two options left. The first is to stick to a traditional cold tank fed system, using pumps if needed to boost pressures. However, if cold tanks in the loft are not an option either, then a pump set is required. This is simply a cold storage tank at lower level, in the garage for example, with pumps to boost the pressure into the house. Once the pump set is operating the property can go ahead with a high pressure and high flow rate cold water supply. Typically two pumps are used in unison - to reduce ware and provide temporary backup if one fails - as the cold tank is lower than outlets, a pump failure will result in a complete failure of water supply, so automatic backup is advised. More on pump sets. Q: How can I work out the size of cylinder I need? A: There are two Flash Tools on this site which will enable you to perform in-depth calculations. As a rule of thumb the following table may help, but values may vary upon general usage levels. You can of course always contact us for advice. Size of store [litres] No of occupants Electric Indirect (Boiler) 1 130 130 2 180 150 3 210 180 4 210-250 180 5 210-300 210 6 250-350 250 Q: Can the plate heat exchanger scale up? A: Generally no. We are often asked by service engineers experienced with combi-boilers about this happening, as they also use a plate heat exchanger to heat water, which can scale up. The main difference between a thermal store and a combi-boiler is the output of the heat exchanger - typically 3 times larger on a Heat Bank. The much higher flow rates generated through the Heat Bank heat exchanger helps to clean it and prevent scale from depositing. It is very rare for
performance to be adversely affected even in hard water areas. However, in hard water areas, we advise choosing the option to factory fit an electronic water conditioner on the Heat Bank. This provides permanent and complete protection against limescale deposits with the heat exchanger. It also protects the rest of the property. More information... Q: Who can I get to install the unit? A: If you do not fancy the job yourself, and do not know a plumber who has been recommended by word of mouth, then use the Institute of Plumbing web site to find the nearest registered plumber. Do not take on the installation yourself if you are not electrically and mechanically competent. ONLY GAS REGISTERED PERSONNEL CAN SERVICE, REMOVE OR INSTALL GAS BOILERS. Q: Can I see a unit before I buy one? A: Our factory in Epsom, Surrey is open 9 to 5 weekdays for anyone to come and see the systems. We also provide free training at the factory for any installers concerned in mains pressure hot water systems, of all types - we also sell and provide technical backup for ALL types of hot water system. Q: Where can I get a new set of instructions? A: We keep all documents, including installation instructions on file. Many Heat Banks instructions are on this site, or can be generated by our Panex program. Alternatively, we can upload a PDF containing your instructions to our web site for you (or maybe your tenants) to download, or view online, when you need. Of course, hard copies may always be sent by post. Q: How do prices compare to your competitors? A: Very well indeed. Our basic range, while still beating the performance of any other system, also compares very favorably to the well known makes on the market. Usually, however, we are asked for system units - rather than a basic unit these also have other controls fitted that would normally be fitted by an installer (e.g. central heating controls). All of our major (high volume) customers take system units, simply because the factory based assembly makes for quicker (and more reliable) assembly and installation and hence lower overall costs and problems on site. Q: Where can I but a Heat Bank? Do Merchants stock units? A: We sell direct, holding a stock of standard sizes. Special sizes can take up to 5 weeks. Limited companies can set up accounts, or else we can take payment by cheque or credit card. On custom units there is a minimum 50% payment with order. Units are delivered either by our own carrier (in the SE) or by outside carrier for longer distances. Units can always be collected if desired. Q: Do you have a local representative who can look at my system? A: We generally only go on site if something goes wrong with our equipment. We do not have a network or sales or technical reps that can provide sales or enquiry help for private customers. We do, however, have a very experience staff who can take on most enquiries with the basic info provided, preferably by email. If we require more info we can always phone you. Where there is volume potential, we have the South covered, and are always willing to attend site meetings. Further afield, we are on the look out for decent technical sales reps (commission only). Q: How does the system comply with the new regulations concerning overheat protection in immersion heaters and thermostatic control of hot water?
A: Our immersion heater have both overheat and dry-fire protection, and we fit a thermostatic blending valve to limit hot water temperatures as standard. If units are to go to care homes requiring special types of temperature control valves, these are available. Q: Are there any disadvantages or hidden costs? A: No. The units are fully pre-fabricated and tested as shown in the specifications, and are not supplied in kit form. The use of our system is rapidly growing in private, trade, new-build and local authority circles as a result of our design and backup. Q: How long have Heat Banks been around? A: Some 10 years plus now. Most of our contracts are within the trade - local authority or new build - and we generally rely on word of mouth and consultants for our main business. The earliest big contracts we had were with London local authorities, with certain major new build companies following, Laing Homes being the first. There are thousands of our units in London, with business as far as Scotland. We have no substantial news paper, or trade press advertising, other than in the Institute of Plumbing magazine, where we often do technical editorials on various subjects. We have always sold to the public, providing customised 1 off specials when needed - see custom unit page - however it is only since the growth of the internet and our web site that we have started to become talked about in domestic circles. Q: What happens is something goes wrong with the unit? A: We provide 1 year on site backup against failures of our equipment. Our site cover is within working hours. We do not provide weekend or evening cover - this is down to your installer. Units have been designed to be simple in regards to wiring (no specialist circuitry) and servicing. Full backup of instructions from our web site. All standard components are available from plumbing merchants (although we provide 2 years cover on these). Please send any technical questions to admin@heatweb.com Please send any sales or price enquiries to sales@heatweb.com Richard Hanson-Graville Technical Director Dedicated Pressure Systems Ltd. All the advantages, None of the disadvantages.
CPC-150-ABBAA Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot water, up to 6 bar pressure. 8 6 7 9 10 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 9 Vent, with evaporation protection 10 Filling Point, with hose 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 53 Y-Pattern Strainer HX14 1 4 11 13 17 16A, 3kW 3 2 53 5 Wiring Diagram: CPC-150-ABBAA Flow Switch
CPC-150-ABIAB Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot 6 7 water, up to 6 bar pressure. 8 30 9 10 28 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 11 20 19 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 18 7 White plastic coated steel casing 8 Anti-vacuum valve 13 16A, 3kW 9 Vent, with evaporation protection 10 Filling Point, with hose HX14 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 18 Lockshield Balancing Valve, 22mm 19 Automatic Air Vent with Manual Vent 1 4 17 20 Three Port Motorised Valve, 22mm 23 Primary pump, Grundfos UPS15-50 28 Danfoss FP715 Two Channel Programmer 30 Danfoss RMT230 Room Thermostat 53 Y-Pattern Strainer 3 2 23 53 5 Wiring Diagram: CPC-150-ABIAB Flow Switch
CPC-150-ABJAB 25 Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot 6 7 26 water, up to 6 bar pressure. 8 30 9 10 28 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 11 20 19 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 18 7 White plastic coated steel casing 8 Anti-vacuum valve 13 16A, 3kW 9 Vent, with evaporation protection 10 Filling Point, with hose HX14 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 18 Lockshield Balancing Valve, 22mm 19 Automatic Air Vent with Manual Vent 1 4 17 20 Three Port Motorised Valve, 22mm 23 Primary pump, Grundfos UPS15-50 25 Primary expansion vessel, 12 litre 26 Primary Pressure relief valve with gauge, 3 bar 27 Primary filling loop 28 Danfoss FP715 Two Channel Programmer 3 2 23 30 Danfoss RMT230 Room Thermostat 53 Y-Pattern Strainer 53 27 5 Wiring Diagram: CPC-150-ABJAB Flow Switch
CPC-180-ABOAB Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot 6 7 water, up to 6 bar pressure. 8 30 9 10 28 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 11 19 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 13 20 18 16A, 3kW 9 Vent, with evaporation protection 10 Filling Point, with hose HX14 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 18 Lockshield Balancing Valve, 22mm 19 Automatic Air Vent with Manual Vent 1 4 17 21 20 Hot Water Zone Valve, 22mm 21 Heating Motorised Valve, 28mm 23 Primary pump, Grundfos UPS15-60 28 Danfoss FP715 Two Channel Programmer 30 Danfoss RMT230 Room Thermostat 53 Y-Pattern Strainer 3 2 23 53 5 Wiring Diagram: CPC-180-ABOAB Flow Switch
CPC-180-ABPAB 25 Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot 6 7 26 water, up to 6 bar pressure. 8 30 9 10 28 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 11 19 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 13 20 18 16A, 3kW 9 Vent, with evaporation protection 10 Filling Point, with hose HX14 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 18 Lockshield Balancing Valve, 22mm 19 Automatic Air Vent with Manual Vent 1 4 17 21 20 Hot Water Zone Valve, 22mm 21 Heating Motorised Valve, 28mm 23 Primary pump, Grundfos UPS15-60 25 Primary expansion vessel, 18 litre 26 Primary Pressure relief valve with gauge, 3 bar 27 Primary filling loop 3 2 23 28 Danfoss FP715 Two Channel Programmer 30 Danfoss RMT230 Room Thermostat 53 Y-Pattern Strainer 53 27 5 Wiring Diagram: CPC-180-ABPAB Flow Switch
CPC-150-ANA Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot water, up to 6 bar pressure. 8 6 7 9 10 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 9 Vent, with evaporation protection 10 Filling Point, with hose 11 Wiring Centre 13 Boost Immersion Heater 14 Economy Immersion Heater 53 Y-Pattern Strainer HX14 1 4 11 13 16A, 3kW 3 2 14 16A, 3kW 53 5 Wiring Diagram: CPC-150-ANA Flow Switch
CPC-150-APA Manually Filled store - NO discharge pipe or overflow. 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot water, up to 6 bar pressure. 8 6 7 9 10 16 16A, 3kW 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 9 Vent, with evaporation protection 10 Filling Point, with hose 11 Wiring Centre 13 Boost Immersion Heater 14 Economy Immersion Heater 16 Economy/Boost Immersion Heater Controller 53 Y-Pattern Strainer HX14 1 4 11 13 3 2 14 53 5 Wiring Diagram: CPC-150-APA Flow Switch
CPC-250-BQ66AAD-AAJD Manually Filled store - NO discharge pipe or overflow. 160kW Plate Heat Exchanger can heat 45 ltr/min of mains hot water, up to 6 bar pressure. 8 6 7 9 10 30 12 51 32A, 6kW 32A, 6kW 1 Plate heat exchanger, L18-28 (160kw+) 2 Flow switch 11 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 49 48 6 Removable lid 7 White plastic coated steel casing 8 Anti-vacuum valve 9 Vent, with evaporation protection 10 Filling Point, with hose HX28 13 11 Wiring Centre 12 Water Level Sensor 13 Immersion Heater 3kW 30 Danfoss TP7000 Programmable Thermostat 1 4 13 44 44 Heating Pump 5m 48 Temperature Gauge 49 Heater Control Stat + Overheat Stat 50 50 Lower Heater Control Stat 51 Immersion Heater Controller Plus 53 Y-Pattern Strainer 3 2 13 13 53 5 Wiring Diagram: CPC-250-BQ66AAD-AAJD 32A, 6kW 32A, 6kW Flow Switch
CXC-150-ABADB-AEBD Connects to a Feed and Expansion Tank (max. 10m head). 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot 8 water, up to 6 bar pressure. 7 30 28 40 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 11 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 7 White plastic coated steel casing 8 Vent 9 Cold Feed 13 16A, 3kW 11 Wiring Centre 13 Boost Immersion Heater HX14 17 Cylinder Thermostat, Immersed [70 C] 28 Danfoss FP715 Two Channel Programmer 30 Danfoss RMT230 Room Thermostat 40 Primary Return Valve, 22mm 44 Heating Pump 5m 1 4 17 17 44 53 Y-Pattern Strainer 3 2 53 9 5 Wiring Diagram: CXC-150-ABADB-AEBD Flow Switch
CXC-180-ABADF-MEMZD Connects to a Feed and Expansion Tank (max. 10m head). 100kW Plate Heat Exchanger can heat 30 ltr/min of mains hot water, up to 6 bar pressure. 7 8 28 30 40 1 Plate heat exchanger, L18-14 (100kw) 2 Flow switch 11 3 Heat exchanger pump 4 Thermostatic mixing valve, RWC Heatguard 22mm 5 Drain off cock 7 White plastic coated steel casing 42 55 48 8 Vent 9 Cold Feed 13 16A, 3kW 11 Wiring Centre 13 Boost Immersion Heater 17 Cylinder Thermostat, Immersed [70 C] 28 Danfoss TS715 Programmer (Hot Water) 30 Danfoss TP7000 Programmable Thermostat 40 Primary Return Valve, 22mm 42 Heating Pump 5m HX14 1 4 17 17 45 44 Heating Pump 5m 48 Temperature Gauge 44 53 Y-Pattern Strainer 55 Solid Fuel / Gravity 1'' Connection 3 2 53 9 55 5 Wiring Diagram: CXC-180-ABADF-MEMZD Flow Switch
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 9-19 Manor Green Road, Epsom, Surrey KT19 8RA Specification 3708-3 Southwark 2 Bed / 1 Bath District Heating Everest 04/12/01 Copies / revised specifications can be obtained via fax / email Heat Bank System Everest combination unit 14 Plate Heat Exchanger (30 ltr/min) Indirect 40mm Foam Insulation Fitted Primary Controls RX1 Programmable Room Thermostat All fitted controls are wired Thermostatic Blending Valve 22mm Backup Immersion Heater Cased Supplied with X100 Inhibitor Unit Code Capacity [litres] 130 150 Base Diameter [mm] 450 450 Overall Diameter [mm] 530 530 Height [mm] 1190 1330 EC-130-3708-3 EC-150-3708-3 2Plate Heat Exchanger 3Heat Exchanger Pump 4Flow Switch 5Thermostatic Blending Valve, Mixcall III 7Automatic Air Vent 8Filling Vent 9Feed to Ball Valve 10Isolating Valve 11Y-Pattern Strainer (supplied loose) 12Overflow 13Cold Feed / Expansion 14Immersion Heater 3kW Incaloy with Stat + Overheat 16Cold Mains In, 22mm 17Hot Mains Out, 22mm 18Drain Cock 19Flow From Boiler 21Flow to Primary Coil 22Return from Primary Coil 33Danfoss Radio Receiver 34 Danfoss TP5 RF Room Thermostat 35aZone Valve - Hot Water 22mm 35b Zone Valve - Heating 22mm (supplied loose) 38Tamperproof Cylinder Thermostat (with Pocket) 39White Coated Steel Casing 42 Wiring Centre with Immersion Switch + Fuses 63Sentinel X100 Corrosion Inhibitor The Heat Bank come with a 3 metre power supply lead, to be wired into a switched 16amp spur. ALL other wiring is completed. The wiring centre [42] includes a 13amp fuse for the immersion heater [14], as well as a 3 amp fuse for controls. Fuses are surface (screw-driver) accessible allowing inspection and replacement without removal of the wiring centre cover. A clearly labeled neon switch is provided for user operation of the immersion heater. The room thermostat [34] communicates with the unit via a digital RF signal removing the need for wiring. The room stat receiver [33] provides the user with manual override / control, should the batteries in the room thermostat fail. The central heating zone valve [35b] actuator is wired into the wiring centre [42], to be installed in pipework by installer. The hot water zone valve [35a] provides an auxiliary switch that can be used to provide the boiler house with a system demand signal.
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 9-19 Manor Green Road, Epsom, Surrey KT19 8RA Specification 3708-4 Southwark 2 Bed / 1 Bath District Heating Everest 25/4/2003 Heat Bank System Everest combination unit 14 Plate Heat Exchanger (30 ltr/min) Indirect 40mm Foam Insulation All fitted controls are wired Thermostatic Blending Valve 22mm Backup Immersion Heater Cased Danfoss RX1 Receiver Back-Plate (wired) Jetseal Ball Valve Supplied with Internal Inhibitor Unit Code CEC-130-3708-4 Capacity [litres] 130 Base Diameter [mm] 450 Overall Diameter [mm] 530 Height [mm] 1190 District Heating Everest 2Plate Heat Exchanger L18-14 3Heat Exchanger Pump 4Flow Switch 5Thermostatic Blending Valve, Mixcall III 7Automatic Air Vent 8Filling Vent 9Jetseal Ball Valve 10Isolating Valve 11Y-Pattern Strainer (supplied loose) 12Overflow 13Cold Feed / Expansion 14Immersion Heater 3kW Incaloy with Stat + Overheat 16Cold Mains In, 22mm 17Hot Mains Out, 22mm 18Drain Cock 21Flow to Primary Coil 22Return from Primary Coil 38Tamperproof Cylinder Thermostat (with Pocket) 39White Coated Steel Casing 42 Wiring Centre 43Back-Plate for Room Stat Receiver 62Magnetic Scale Inhibitor 3/4"BSP MI 1.5 litres of Corrosion Inhibitor is supplied, already added into the store, following factory testing of the unit. Should the unit be drained down after initial filling, fresh inhibitor will be required.
DEDICATED PRESSURE SYSTEMS LTD. Specification 4675-1 No.2 Neckinger Estate, Southwark Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 9-19 Manor Green Road, Epsom, Surrey KT19 8RA 11/06/03 Heat Bank System Everest combination unit 28 Plate Heat Exchanger (45+ ltr/min) Indirect 40mm Foam Insulation High duty primary coil S-Plan primary controls Twin Cylinder Thermostat Arrangement DO NOT USE Fitted programmer All fitted controls are wired Thermostatic Blending Valve, Heatguard 22mm 28mm Primaries LWC1 Wiring Centre Backup Immersion Heater Cased Everest Heat Bank, Indirect S-Plan Unit Code Capacity [litres] 210 300 Base Diameter [mm] 450 500 Overall Diameter [mm] 530 580 Height [mm] 1720 1900 CEC-210-4675-1 CEC-300-4675-1 2Plate Heat Exchanger 3Heat Exchanger Pump 4Flow Switch 5Thermostatic Blending Valve, RWC Heatguard 22mm 7Automatic Air Vent 8Filling Vent 9Store Filling Point 9Feed to Ball Valve 10Isolating Valve 11Y-Pattern Strainer (supplied loose) 12Overflow 13Cold Feed / Expansion 14Immersion Heater 3kW Incaloy with Stat 16Cold Mains In, 22mm 17Hot Mains Out, 22mm 18Drain Cock 19Flow From Boiler 28mm 21Flow to Primary Coil 22Return from Primary Coil 23Flow to Heating 28mm 25By-Pass Connection 22mm 29Primary Coil Balancing Valve 33Programmer Danfoss CP715 34 Room Thermostat (supplied loose) 35aTwo Port Zone Valve - Hot Water 22mm 35bTwo Port Zone Valve - Heating 28mm 38Cylinder Thermostat (with Immersion Pocket)
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 9-19 Manor Green Road, Epsom, Surrey KT19 8RA Specification 4388-2 London Borough of Southwark Under Worktop Xcel Heat Bank GXV100 11/04/02 Xcel Heat Bank System 28 Plate Heat Exchanger (45+ ltr/min) Directly heated from remote source 40mm Foam Insulation GX-Plan primary controls Fitted Primary Controls Cased Unit Code Capacity [litres] 100 Base Diameter [mm] 400 Overall Diameter [mm] 480 Height [mm] 850 CXC-100-4388-2 2Plate Heat Exchanger, L18-28 3Heat Exchanger Pump, UPS15/50 4Flow Switch 5 Thermostatic Blending Valve (1", pre-set to 8 Vent, 3/4"FI (Blanked) 11Y-Pattern Strainer (supplied loose) 13Cold Feed / Expansion, 3/4"FI (Blanked) 15 Immersion Heater 3kW with 2 stats 16Cold Mains In, 22mm 17Hot Mains Out, 22mm 18Drain Cock 19Flow From Boiler, 22mm 20Return to Boiler, 22mm 23Flow to Heating Circuit, 22mm 24Return from Heating Circuit, 22mm 27Primary Pump, UPS 15/50 34 Room Thermostat 38Cylinder Thermostat (Tamperproof, pre-set to 75 C) 39White Coated Steel Casing 41Primary Blending Valve Heatguard UF (Pre-set to 4) 42Terminal Box WB12 with relay The GX100 Heat Bank provides both mains pressure, temperature controlled, hot water, at up to 40 litres per minute, and 10 bar pressure. The store also provides fully pumped central heating.the store is very small, capable of hiding under a kitchen worktop, and has very low standing heat losses. It can however, deliver a full bath in under 4 minutes, with hot water to spare, and follow up with another bath within 15 minutes of the first. Also, radiators can be brought up to full temperature in under a minute of turning the heating on. Mechanical installation consists of simple push fit-pipework connections, and the only site wiring required is connection to the mains electrical supply, boiler and room thermostat. Being a fully vented thermal store, the system can be installed by installers not qualified to install unvented systems. As standard, the store is on 24hrs a day, with the room thermostat being the only control the householder need use. A backup 3kW immersion heater provides backup central heating and hot water in case of boiler failure. All components are tamperproof.
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com SPECIFICATION 3755-1 London Borough of Southwark STS Energy Management 09/05/01 210 litre Grade 3 Cylinder (max 1 bar) Indirect BS 28mm Coil Finned 6m Solar Coil 40mm Foam Insulation Danfoss Y-Plan Controls PCB Primary Wiring Centre Fitted Primary Pump, 5m head Fitted Solar Controls Resol Delta Pro Solar Controller All fitted controls are wired HWS Thermostatic Blending Valve Backup Immersion Heater Unit Code ECON-3755-1 Capacity [litres] 210 Base Diameter [mm] 450 Overall Diameter [mm] 520 Height [mm] 1550 1Cold Feed 22mm 2 Hot Water Services 22mm 3 HWS Thermostatic Blending Valve 4 Isolating Valve 7Automatic Air Vent 8Vent 13 Drain Cock 14Immersion Heater 3kW Incaloy with Stat 19Flow From Boiler 21Flow to Primary Coil 22Return to Boiler 23Flow to Heating Circuit 26Primary Pump UPS 15/50 29Primary Coil Balancing Valve 33 Danfoss Programmer CP715 38Danfoss Cylinder Thermostat 35Danfoss Three Port Mid Position Valve 36 Danfoss RF Radio Rom Thermostat 37 Danfoss RX1 RF Receiver Unit 38 Automatic By-Pass Valve 39White Coated Steel Casing 42Wiring Centre 48Check Valve 49Solar Drain Point 50Solar Pump UPS 15/50 51Flow from Solar Panels 52Return to Solar Panels 53Resol Solar Controller 54 Flow Meter 73Sensor Points 80Solar Filling Point 81Dosing Pot Connection
DEDICATED PRESSURE SYSTEMS LTD. SPECIFICATION 2023-2 Wicken Engineering / Slough Borough Council Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com R/O Shops, 9-19 Manor Green Road, Epsom, Surrey KT19 8RA 20/4/01 Stowaway advanced Heat Bank System Manual Fill - No Overflows 40mm Foam Insulation with Casing HWS Heat Exchanger (100kW) HWS Blending Valve Primary Heat Exchanger (14kW peak) Directly Pumped Heating Circuit Fitted Primary Pumps All fitted controls are wired Low Water Level Indicator Blanked Immersion Heater boss Coated Steel Casing, with Film Cover Heat Meter, Class C with Impeller Differential Pressure Control 1Integral Expansion Vessel(18 ltr) 2a HWSPlate Heat Exchanger 2bPrimary Plate Heat Exchanger 3Heat Exchanger Pump UPS 15/50 4Flow Switch 5Thermostatic Blending Valve 6Manual Air Vent 7 Automatic Air Vent 8Integral Overflow Chamber 9System Filling Point 11Y-Pattern Strainer (supplied loose) 14 Blanked Immersion Boss 2 1/4" 16Cold Mains In, 22mm 17Hot Mains Out, 22mm 18Drain Cock 23Flow to Heating Circuit 24Return from Heating Circuit 25 Primary Flow 26 Primary Return 27Primary HX Pump UPS 15/60 28Heating Circuit Pump UPS 15/60 29 Primary Isolating Valve 30 Motorised 2-Port Valve 33 Programmer 34 Room Thermostat (supplied loose) 38 Cylinder Thermostat 39White Coated Steel Casing 40Tight Fitting Lid 41 Primary Blending Valve 42Wiring Centre 54Filling Loop (disconnect after use) 55Water Level Switch 65Manual Water Level Test and Drain 70 Flow Meter 71 Class C Heat Meter 72 Temperature Sensors 73 Differential Pressure Control Valve 74 Pressure Sensing Points Unit Code SC-130-2023 Capacity [litres] 130 Base Diameter [mm] 400 Overall Diameter [mm] 480 Height [mm] 1500
The use of a Primary Plate Heat Exchanger isolates the District Primaries from the Property Primaries, preventing crosscontamination, and allowing effective dosing of individual systems. A Mains Water Isolating Lever Valve must be fitted within the cylinder cupboard, in clear view and easily accessible. A Strainer (supplied loose) must also be fitted, down stream of the isolating valve, to protect the flow switch [4]. The Wiring Centre [42] is fitted with a neon which indicates when the unit needs topping-up. It is also fitted with a relay to prevent the Heat Exchanger Pump [3] from activating - there will be no hot water available until the unit is topped up manually, using the filling loop [8]. The unit is fitted with a Mixcall III Thermostatic Blending Valve, to control the hot water temperature, and prevent scalding. The graph shows the pressure drop across the valve for various hot water flow rates. The Valve is adjustable from 27 C to 67 C, and has a lockable head. The unit is fitted with an Integral Overflow Chamber [8], which traps small volumes of water discharged as a result of overfilling. Water in the chamber can be drained off via the Overfill Drain Cock [66]. The unit MUST be watched during filling as excessive overfilling will result in over-spill onto the floor. It is advised that the mains water is tested for hardness. In areas of hard water, we advise the use of a scale inhibitor. It is important that SENTINEL X100 Inhibitor is used to protect the Heat Bank. Use 1 litre per 100 litres of stored water. A suitable anti-freeze, such as X500, should also be added when there is a chance that the unit will be left filled and unheated in freezing conditions.
DEDICATED PRESSURE SYSTEMS LTD. Specification 5116-1 Wicken Engineering Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 9-19 Manor Green Road, Epsom, Surrey KT19 8RA 24/09/02 Heating Distribution Board 1 Quarter-Turn Ball Valve 2 3/4" Ply Backboard 3 Y-Pattern Strainer 4 Grundfoss 15-60 Pump 5 Two-Port Motorised Valve 6 Lockshield Valve By-Pass 7 Wiring Centre 8 STROMAX-GM Circuit Regulating Valve 3/4"
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 17 Manor Green Road, Epsom, Surrey KT19 8RA Company No.: 2963502 V.A.T. No.: 644221955 PANDORA CENTRAL BOILER APPLICATION Sample of letter to customer regarding design options. DPS Ref: 16181 This Design will: 1. Obtain an 85-55 C drop on primaries for heating, with a fixed flow rate giving 9kW input. 2. Deliver thermostatically controlled mains pressure domestic hot water at up to 24 l/min @ 6 bar. 3. Deliver central heating with a 30 litre buffer, giving rapid initial heat-up. 4. Provide 3kW electric backup to both hot water and optionally heating. 5. Requires no discharge, with store/heating system manually filled. 6 Requires no annual maintenance. As we cannot vary the flow to match low load heating, it is not possible to maintain a low return temperature, UNLESS the heating is separated from the input using some storage as a buffer. The basic idea is that the primaries are only opened for recovery once the bottom 30 litres of the store has dropped below 55 C (as detected by the upper thermostat). The primaries are then opened to recover the 50 C water up to 75 C. Once the 30 litres has been circulated through and has reached 70 C the lower thermostat turns off the primaries. (the lower stat needs to be set between 55 C and 70 C - say 65 C). At full load the radiator flow/rtn will be 75/50 C. Bottom section will circulate once only. Primaries will open, and if gradually the lower section will reheat as most heat is going straight to central heating. At low load the initial radiator flow may be 75/40 C. The flow rate will be much lower so it will take a while for the lower 30 litres to be circulated. Once the primaries open, the lower section may recover 40/70 C and recovery will stop. the heating will now continue at say 70/45 C... and the cycle continues. At all times the primary return temperatures should be at or below the desired maximum of 55 C. Another way of saying same thing... We are trying to cool down the primaries to below 55 C. Because there is a set primary flow rate, it is not possible to cool the primaries enough at low heating loads unless... We run the heating off stored heat until we have a reservoir of water cool enough to run and cool the primaries to 55 C. You cannot even do this with a distribution board, unless you are allowed to reduce the primary flow rate to match load using a thermostatic valve. The thermostatic valves required to get a set point over 65 C are the Danfoss AVTB valve and the motorised valve still used for tight shut-off.
I have shown a motorised two port valve on the primaries. I assume one must be required, and we can fit and wire if needed. Also a room thermostat as this completes the necessary controls (unless a timer is also needed). The immersion heater can be lowered into the bottom section if you would like backup electric central heating. In the position shown it will be hot water only. My selection of heat exchange is our largest stock unit the M18-30. This size gets the htg rtn to within 3 C of primary rtn. Cheaper heat exchangers are available if this temp difference can be increased. Software gives following: Only issue is flow rate. I believe to make use of any available Grundfos pump, the flow rate is too low so a by-pass will be required around the pump, to put is somewhere on the curve. This can be a lockshield valve, an auto-by-pass or fixed orifice. Also, it may be worth having a Tacometer flow gauge on the store flow through the heat exchanger to allow visual indication and setting of flow rate.
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com 17 Manor Green Road, Epsom, Surrey KT19 8RA Company No.: 2963502 V.A.T. No.: 644221955 Schematic Installation of FT-XCEL
DEDICATED PRESSURE SYSTEMS LTD. Telephone 01372 803 675 Fax 01372 803 678 Email dps@heatweb.com Internet http://www.heatweb.com Operation of the GX Heat Bank (Patented DPS Technology) The GX Heat Bank was originally designed to meet a very specific local authority requirement for a small, efficient, high performance, mains pressure hot water and heating system, that was also easy to install. Components were to be easy to service, with reliability designed in. A cylinder small enough to fit under a kitchen worktop should be capable of driving a three bedroom house.
Mains Pressure Hot Water: It is well established that plate heat exchangers can provide lashings of hot water, and isolate the store from both mains water pressures and contaminants (salts, scale etc.). We offer a range of heat exchanger duties, with the standard model providing 100kW of hot water. To ensure exceptional reliability, the flow switch is of our own custom made design, able to take high flow rates with a low pressure loss, has no internal springs or paddles, has solid simple electrics, and is jam and leak free. Central Heating: The central heating water is pumped directly from the store. The radiator system has access to the lower portion of the store to drive radiators, and can respond very rapidly to sharp increases in heating demand. It is however unable to draw the upper section of the store into circulation, ensuring continued hot water supplies. The absence of motorised valves, simplifies wiring, makes servicing easier, reduces pressure losses as well as costs. As there is a buffer store between the boiler and the heating, there is reduced cycling of the boiler. Recovery: The unique aspect of the GX is its method of recovering through use of a boiler. The aim of the design is to ensure all energy from the boiler is made immediately available for hot water - and at usable temperatures. Additionally, when used in conjunction with a condensing boiler, the system can ensure that return temperatures are kept within condensing levels. The return temperature is fixed by the use of a thermostatic blending valve which mixes hot flow water with colder store water to obtain the target temperature. The system can pull into immediate use relatively hot water returning from the heat exchanger or radiator circuit, and pass it directly through to the boiler and back to the top of the store for immediate use.
75 C TIMER 75 C PLATE HEAT EXCHANGER HWS BLENDING VALVE + BOILER - HWS STAT + - BLENDER 55 C PUMP +20 C 55 C PUMP FLOW SWITCH COLD MAINS HOT WATER RESERVE ROOM STAT TIMER PUMP CENTRAL HEATING CIRCUIT BLENDER UNDERFLOOR CONTROLS TIMER + - DPS GX HEAT BANKS A little more than the standard options HEAT IN GAS OR OIL BOILER HEAT OUT MAIN PRESSURE HOT WATER ELECTRIC HEATERS RADIATORS TIMER / SWITCH BOOST HEATER TIMER ECONOMY HEATER SOLAR STAT SOLAR PANEL UNDERFLOOR HEATING CONTROLLER EXPANSION VESSEL STAT PRESSURE GAUGE PUMP UNDERFLOOR HEATING CIRCUIT PUMP FILLING LOOP SOLID FUEL SWIMMING POOL PUMP SWIMMING POOL PLATE HEAT EXCHANGER PUMP SOLID FUEL BOILER WOOD BURNER
Steel Tanks MAINS HOT WATER One of the many benefits of thermal stores, is that the stored water is under no pressure - even though the hot water supplied is at mains pressures. This allows us to build rectangular storage tanks, rather than circular, making better use of space. The tanks can be surprisingly small when compared to cylinders of the same capacity. For example, take the 550 x 650mm tank and a cylinder 500mm diameter. The tank is only 60% the height of the cylinder. The following pictures show a fully assembled (as delivered) Heat Bank Pandora Tank, providing mains pressure hot water, and including all controls for a fully pumped and sealed heating system - just add basic boiler and rads!
110L 645 835 165 326 DPS
HEAT BANK TANK CASED Dedicated Pressure Systems Ltd. 165 130 3/4"FI 165 130 SHEET7970-6 03-01-06 60 1"FI DIFFUSER TUBE 1/2" FI 3/4"FI 1/2" FI 1.1/4" 1.1/4" 1.1/4" 1.1/4" 110 50mm INSULATION 22mm 16 Turn Coil 22mm 1/2" FI 40 60 1/2" FI 1050 270 220 DIFFUSER TUBE DIFFUSER TUBE 1/2" FI 200 DIFFUSER TUBE 75 1.1/4" 1"FI 980 900 3/4"FI UNIT CODE WIDTH (MM) DEPTH (MM) CAPACITY LITRES STORE HEIGHT CXT590-6 550 550 590 OUTER CASING 650 650 1950 2000