K18 PLANT MANUAL. Heating and DHW

K18 PLANT MANUAL Heating and DHW 0 - INTRODUCTION This document provides the guidelines on how the Gas Absorption Heat Pump GAHP K18 operates, how to use it and how a designer or a qualified installer should focus on specific topics in order to design and build a plant working with a GAHP K18. The contents in this manual are an integration of the Instruction Manuals of the GAHP and the OQLT017 System Controller (if present). 1 INDEX Chapter 1 Selection criteria Chapter 2 GAHP K18 Technical Data Chapter 3 Plant design, P&I schematics Pagina1

CHAPTER 1 SELECTION CRITERIA Q: Which is the building right size for a typical K18 installation? A: You should consider the actual thermal load and the additional functions instead of the size of the building. For instance, you can always provide DHW while a 120sqm building not well insulated may require the same thermal load of a well-insulated 300sqm one. Q: Which kinds of building are suitable for the K18 heat pump? A: Considering the right thermal load, we can consider one and two-family dwellings, even if already built. Q: Can the K18 be installed in an existing building with high temperature radiators (70/80 C)? A: Yes. The K18 can deliver hot water up to 65 C, a temperature enough for heating even during the coldest seasons, in fact: 1. The radiators dimensions are commonly oversized. 2. The heating power peak is typically calculated on the few coldest hours during night time for only a few days per year and doesn t consider the thermal inertia of the building itself that can compensate the temporary deficit of power. 3. Very often old buildings have been improved with thermal insulation actions (e.g. new window frames). With the K18 the old boiler replacement or integration becomes easier and faster. Q: Which are the advantages of a K18 in comparison with an Electric Heat Pump? A: Mainly but not only: The K18 electrical power need is really low: less than half a kw against more than 5 kw required by the electric technology; The K18 is able to perform well even when the external air temperature drops a lot; as a consequence of this, there is no need of power integration with an electric resistance. Due to this, extra energy savings are guaranteed also; The K18 technology is not involved in the F-Gas regulation; in fact it uses a natural refrigerant without any restriction or any specific maintenance. Pagina2

Q: May the K18 be managed by an already installed BMS? A: Yes. You can turn on the unit with a voltage-free contact or through the MODBUS protocol (normally with a BMS). Q: Can you manage the K18 together with an existing boiler? A: Yes, you can manage a third party boiler with the optional System Controller. The boiler will be used only if the K18 power will need to be integrated. Q: How will you manage exhaust piping? A: With 40 Pa of residual head, you can easily bring exhaust pipes up to the roof. Depending on the local normative, you can also manage flue gas exhaust on the wall. Q: K18 is for outdoor installation. Which is the best positioning strategy for the unit looking at the relative building? A: In order to avoid the most possible any unnecessary thermal dispersion due to connection pipes, the closer to the building, the better. You must only guarantee enough air circulation for the finned coil and the fan, and avoid any trouble with people or pets. Q: Is always the existing pipe system to be cleaned before installing the K18? A: Yes, it is. Dust and residual metal powder may reduce the K18 heat exchanger efficiency. Please, follow the pipe cleaning procedure that you can find in the K18 installation manual. Q: which is the optimal design temperature for an air source heat pump? Heat Pumps performances are strongly depending on the water delivery temperature. A variable set point that follows the actual external air temperature is recommended (e.g. 55/60 C when the outdoor temperature is around -5 C; 45/55 C when outdoor temperature is above 0 C). The K18 is ready to work with a variable set point without any further component. With this approach you will slightly improve the seasonal efficiency. Pagina3

CHAPTER 2 GAHP K18 TECHNICAL DATA In the table below, the available thermal power, depending on the external air and the water delivery temperature: DESIGN POWER DEMAND Design ambient Temp [ C] High Temperature System - 55 C Low Temperature System - 35 C -25 12,0 13,0-20 12,0 14,0-15 12,5 15,0-10 13,0 16,0-5 14,0 17,0 0 15,0 18,0 5 16,0 18,5 10 17,0 19,0 DATI UTILI ALLA COMPILAZIONE DELLA CERTIFICAZIONE ENERGETICA Temperture range θ tol -25 C Generator Temperature θ gen,in 90 C Electrical Power Absorption 0,28 kw Heating Capacity ϕ gahp,in 11,2 kw Modulation range (min) 60 % GUE - K 18 θ f - C θ c - C 35 45 55-7 149 131 113 2 161 153 134 7 169 161 144 12 171 166 153 Further technical data are available in the K18 Instruction Manual. Thermal Power ϕ gahp,out - K 18 θ f - C θ c - C 35 45 55-7 17,5 15,4 13,3 2 18,4 17,4 15,3 7 18,9 18,0 16,1 12 18,8 18,3 16,8 Pagina4

Q: Does the K18 has its own water circulation pump? A: The K18 is available with or without onboard circulation pump. Q: Does the onboard water pump need a secondary pump towards the plant or is it ready to be used alone? A: An additional secondary water pump can be installed, depending on the existing plant features. The K18 water pump has a residual head of 40 kpa @1.500 l/h Q: Can the external circulation pump be directly managed by the K18? A: Yes, and it is the best option. This way the K18 will be able to manage the water pump according to the Heat Pump operating mode. Moreover also the active anti-icing cycle will be managed, i.e. the water pump will be connected to the electronic board of the unit and turned on in case of too-low water temperature Q: Is a buffer tank needed for the heating water circuit? A: After several tests, it has been proved that even a small buffer tank (100 liters) will dramatically improve the system seasonal efficiency, especially during partial-load operating mode (the most common working condition during the heating season). The bigger the buffer volume, the most the efficiency gain. Q: How the DHW production is managed with the K18? A: The K18 will work on a serpentine in the DHW production tank. Its volume will depend on the characteristics of the end user needs (number of people, number of bathrooms, et cetera). 200-300 liters are usually enough. The serpentine must have a wide surface, enough for the power exchange that must be guaranteed between the K18 and the DHW in the tank (3-4 sqm for the 200-300 liter tank). The System Controller (optional) will manage the right water delivery temperature and the 3-way valve. Q: What about the legionella cycle? A: The GAHP K18 can produce hot water up to 70 C (return temperature up to 60 C). With this temperature range you can eventually manage a thermal legionella cycle. Anyway other options are available, like UV rays, micro-filters and chemical treatments with chlorine dioxide or hydrogen peroxide. Pagina5

AVAILABLE MODELS Residual head of the high efficiency circulator pump: 40kPa@1500l/h Electrical power need: 75 W STANDARD EQUIPMENT Ambient temperature probe Climatic curve available without any optional accessory Remote water delivery temperature probe Modulating fan Pagina 6 GAHP K 18 PLANT MANUAL 07.01.2015

OPTIONALS In order to optimize the performance and to the overall the management of the K18, the following optional have been made available. The standard components not in the list can be sourced on the market. SYSTEM CONTROLLER (O-QLT017) The System Controller is very important to guarantee energy savings and an optimal efficiency in HVAC solutions. Therefore, also the secondary components, like circulators, room thermostats, valves, auxiliary boiler, et cetera, are to be managed. The K18 Controller has been fine tuned to guarantee all the above. Pagina7

Ability of the System Controller: - it manages the room temperatures; - it manages the DHW production; - it manages the K18 and, if needed, an auxiliary boiler. The System Controller is composed of: - Control Box, with the electronic board, some relays and electric plugs. - Room Unit, a remote controller to set and adjust the k18 and all the appliances connected to the Control Box, which acts also as an enhanced Chronothermostat. In fact it is always a good option installing the indoor Room Unit in the same room where you need the comfort temperature, replacing the existing one. This way the controller will force the water setpoint according the actual power needed by the building; in case the climatic curve based on the external air temperature will be adjusted and the ON/OFFs reduced. - External air probe for the climatic curve managing In the following chapter you will find some plant layouts, with and without the System Controller, that were designed in order to simplify the installer operation with some preconfigured parameter settings, and the user experience with a selection of user-friendly parameters. Pagina8

PART 3 PLANT DESIGN, HYDRAULIC AND ELECTRICAL SCHEMES BASIC HYDRAULIC PLANT The following components must be installed on the hydraulic plant: NOTES Expansion tank: it must be sized according to the water content of the plant, considering also water content of the unit and pipes (approximately 4 liters of tank per 100 liters of water content). Separator filter: must be installed when the plant already exists, because of possible impurities contained in it. It may be replaced by a simple Y filter in case of new plants. Control valve: required when a modulating pump is not used. Buffer tank: required to ensure a minimum load to the unit during periods of medium/low thermal load of the building. The size of the tank can be increased. In the minimum volume (100 liters) can be included also the volume of pipes between unit and buffer tank. Do not use glycol, if possible. The unit is equipped with anti freeze system, in order to keep water temperature above zero: for this reason the unit must be always connected to gas and power supply. Pagina9

ONLY HEATING PLANT ONE HYDRAULIC CIRCUIT (SCHEME 1) Heating plant for the production of hot water up to 65 C (without DHW production), no hydraulic separation. NOTES chronothermostat Water circulation: verify that there is always water circulation in the system. In case of using, for example, thermostatic valves, don t install them on one or two radiators. Is also possible to avoid installation or remove valves in the room where is located chronothermostat. Always install buffer tank to ensure a minimum load to the unit during periods of medium/low thermal load of the building. The control of the unit is made by an external consense from a device, such as a room thermostat, a chronothermostat or some thermostats in parallel that close a contact. The unit is equipped with external temperature probe in order to control climatic curve to optimize performance during periods of medium/low heating load. Is possible to change parameters of the climatic curve from the electronic board of the unit. SCHEME 1 Pagina10

OPTIONALS AND ELECTRICAL WIRING BETWEEN GAHP K18 AND PLANT For further details about wiring of GAHP K18 refer to Installation Manual. SCHEME 1 COMPONENTS REQUIRED FOR THE INSTALLATION of K18 version: with circulating pump without circulating pump OCDS005 Ambient chronothermostat OQLT017 System controller OSRB012 200 liters DHW tank (3 sq.m. coil surface) OSRB004-300 liters DHW tank (4 sq.m. coil surface) OVLV007 Three way diverting valve to switch heating/dhw OSND003 External air temperature probe OSND004 Immersion temperature probe: n. probes OPMP009 Modulating pump 7,5 m head OPMP004 Modulating pump 10 m head ONTV014 Anti vibration supports Pagina11

ONLY HEATING PLANT - TWO HYDRAULIC CIRCUITS WITH ONE CIRCULATING PUMP (SCHEME 2) Heating plant for the production of hot water up to 65 C (without DHW production) with two heating circuits and one pump. SCHEME 2 NOTES: Water circulation: verify that there is always water circulation in the system. When using, for example, 2-way valves for each circuit, connect the chronothermostats and 2-way valves to the system controller, in order to turn off the unit and the circulator when both thermostats are OFF. Insert between delivery and return to the plant an overpressure valve, to ensure water circulation when 2-way valves are closed and K18 activates antifreeze function. The control of the unit is ensured by System controller, to which chronothermostats are connected. System controller manages climatic curves (one curve for each zone) to optimize performance during periods of medium/low heating load. Is possible to change parameters of the climatic curve on the Plant controller. Pagina12

OPTIONALS AND ELECTRICAL WIRING BETWEEN GAHP K18 AND SYSTEM CONTROLLER For further details about wiring of GAHP K18, System Controller and other devices (thermostats, pumps, etc.) refer to related Manuals. SCHEME 2 COMPONENTS REQUIRED FOR THE INSTALLATION of K18 version: with circulating pump without circulating pump OCDS005 Ambient chronothermostat OQLT017 System controller OSRB012 200 liters DHW tank (3 sq.m. coil surface) OSRB004-300 liters DHW tank (4 sq.m. coil surface) OVLV007 Three way diverting valve to switch heating/dhw OSND003 External air temperature probe OSND004 Immersion temperature probe: n. probes OPMP009 Modulating pump 7,5 m head OPMP004 Modulating pump 10 m head ONTV014 Anti vibration supports Pagina13

ONLY HEATING PLANT - TWO HYDRAULIC CIRCUITS, ONLY ONE CIRCUIT MIXED (SCHEME 3) Heating plant for the production of hot water up to 65 C (without DHW production) with two heating circuits, the first is direct (radiators) and the second with mixing valve (radiant floor). Components required for the installation - System controller (mandatory optional) - Immersion temperature probe (optional) - Circulating pump for direct circuit (optional) - Circulating pump for mixed circuit (optional) - mixing valve and actuator (optional) - Anti vibration supports (optional) NOTES : refer to scheme 2. About electrical wiring, refer to scheme 2. SCHEME 3 Pagina14

SCHEME 3 COMPONENTS REQUIRED FOR THE INSTALLATION of K18 version: with circulating pump without circulating pump OCDS005 Ambient chronothermostat OQLT017 System controller OSRB012 200 liters DHW tank (3 sq.m. coil surface) OSRB004-300 liters DHW tank (4 sq.m. coil surface) OVLV007 Three way diverting valve to switch heating/dhw OSND003 External air temperature probe OSND004 Immersion temperature probe: n. _1_ probes OPMP009 Modulating pump 7,5 m head (the alternative is OPMP004) OPMP004 Modulating pump 10 m head ONTV014 Anti vibration supports Pagina15

ONLY HEATING PLANT WITH AUXILIARY BOILER (SCHEME 4) Heating plant for the production of hot water up to 65 C (without DHW production) with one or two heating circuits (refer to scheme 1, 2 or 3), the boiler is new or already existing. NOTES : refer to scheme 2. The boiler must be connected to the System controller in order to activate it when GAHP K18 unit cannot satisfy the heating request of the building (this situation may happen for few days per year when external temperatures are close to design temperature). About electrical wirings, refer to scheme 2. SCHEME 4 Pagina16

SCHEME 4 COMPONENTS REQUIRED FOR THE INSTALLATION of K18 version: with circulating pump without circulating pump OCDS005 Ambient chronothermostat OQLT017 System controller OSRB012 200 liters DHW tank (3 sq.m. coil surface) OSRB004-300 liters DHW tank (4 sq.m. coil surface) OVLV007 Three way diverting valve to switch heating/dhw OSND003 External air temperature probe OSND004 Immersion temperature probe: n. _2_ probes OPMP009 Modulating pump 7,5 m head (the alternative is OPMP004) OPMP004 Modulating pump 10 m head ONTV014 Anti vibration supports Pagina17

HEATING PLANT AND DHW PRODUCTION (SCHEME 5) It is possible to produce domestic hot water using a tank with internal coil which must be sized according with maximum delivery temperature of the heat pump. In the scheme below is represented heating plant and DHW production provided with auxiliary boiler and heat pump. There are two heating circuits, the first is direct and the second mixed. NOTES: refer to scheme 2. Diverting valve (optional) and temperature probe in DHW tank must be connected to System controller in order to manage DHW production. About electrical wirings, refer to scheme 2. SCHEME 5 SCHEME 5 Pagina18

COMPONENTS REQUIRED FOR THE INSTALLATION of K18 version: with circulating pump without circulating pump OCDS005 Ambient chronothermostat OQLT017 System controller OSRB012 200 liters DHW tank (3 sq.m. coil surface) OSRB004-300 liters DHW tank (4 sq.m. coil surface) OVLV007 Three way diverting valve to switch heating/dhw OSND003 External air temperature probe OSND004 Immersion temperature probe: n. _4_ probes OPMP009 Modulating pump 7,5 m head (the alternative is OPMP004) OPMP004 Modulating pump 10 m head ONTV014 Anti vibration supports REQUIRED CONNECTIONS Pagina19

The unit needs the following connections: - gas supply (maximum consumption is 1,2 m 3 /h). - power supply at 230 V (maximum power consumption is 280 W, water circulating pump is excluded). - electrical wirings for the control of the unit, to be connected to devices inside the building. - hydraulic connections to water inlet and outlet. Water charge can be realized on water pipes of the plant inside the building. - exhaust flue gas from the burner (for a correct discharge refer to local regulations). - Flue gas condense drain and defrosting water drainage (from the finned coil). The details about position and diameters of these connections are explained in the Installation manual of GAHP K18 unit. Pagina20

To prepare hydraulic, electrical and discharge connections refer to the scheme below. Hydraulic connections diameter: ¾ M Gas connection diameter: 3/8 M Exhaust flue gas diameter: 60 mm Maximum gas consumption: 1,2 m 3 /h Maximum power consumption GAHP unit: 280 W Pump power consumption (if included): 75 W Pagina21

D-MNL049 rev.a 15MEDSDC005 12/09/2015 Con l obiettivo di migliorare la qualità dei prodotti, Robur si riserva di variare e aggiornare i dati e le informazioni riportate in questo documento. PRONTUARIO GAHP K 18 07.01.2015