Nimbus Compact M NET R32 Installation Manual UK

Hydraulic connections

Hydraulic connections 4.1.6 Characteristics of the supply water Make sure that the system is supplied with water having a hardness between 4.5°dH (8°fH) and 8.4°dH (15°fH) and conductivity below 500μS/cm. In zones where the water is particularly hard, mount a water softener. If the system is filled with water that is aggressive (the pH should be maintained between 7.5 and 9), ferruginous or hard, use treated water to prevent limescale build-up, corrosion and damages to the appliance. Even a slight quantity of impurities in the water may decrease system performance. The filling water used must strictly be treated in the case of high-capacity installations (high volumes of water) or if frequent water top-ups are required to maintain a constant level of liquid in the system. If the system must be cleaned, fill it completely with treated water. Glycol adversely affects the appliance’s performances and we strongly advise not to use it. If glycol is nonetheless used, ARIS- TON shall not be held liable for any loss of efficiency of the system and recommends dosing it properly and performing maintenance. 4.1.7 Filling the system During filling, it may not be possible to remove all the air from the system. The residual air will be removed through the automatic air relief valves during the initial hours of operation of the system. If the system’s pressure drops excessively, fill the circuit with water. a a The installation, initial start up, and configuration must be carried out in accordance with the instructions, by qualified and competent installer only. The manufacturer declines all responsibility for damages caused to people, animals or possessions following incorrect installation of the appliance. During initial filling of the system, check the outflow of water from the automatic relief outlet. The water outflow makes the sealing discs inside the valve work effectively. We recommend performing the operation with a cloth to absorb the excess water. To speed up filling of the system, the system can be deaerated manually as follows: – Mount the pipe (1) supplied on the manual deaerator outlet. – Open the manual deaerator (2) and channel the water towards the outside the machine. – Deaerate the system for a few minutes until all the air has been removed from the pipes. – Close the deaerator. 1-ZONE configuration a 2 1 Fig. 46 The accumulation of air can cause malfunctions to the system and damage the components. Note: during the initial start-up the automatic deaeration function is activated, which is necessary to ensure the system’s correct operation. The activation of the automatic deaeration cycles of the system following the initial start-up can be performed using the Air-purge function 1.12.0 command. a The indoor unit contains a pressure gauge which can be accessed by the installer during the first filling phase. The system’s pressure can nonetheless be read through the system interface (parameter 1.16.7). If the interface is not installed on the machine, we recommend using an external pressure gauge to check the pressure and allow the user to fill the system with water. Check the water pressure on the pressure gauge regularly and make sure that the pressure is between 0.05 MPa (0.5 bar) and 0.15 MPa (1.5 bar) when the system is cold. If the pressure is below the minimum value, it must be increased through the filling cock. Close the cock once the average value of 0.12 MPa (1.2 bar) has been reached. The minimum pressure of the heating/cooling system is 0.05 MPa (0.5 bar). The maximum pressure of the heating/cooling system is 0.3 MPa (3 bar). a If frequent fillings (once a month or more frequently) are required for your system, this indicates a potential problem with the installation (leaks, expansion vessel problems). Contact your trusted installer to analyse and solve the problem quickly, and to prevent damage caused by corrosion of the components due to excessive water replacement in the system. 28 / EN

Hydraulic connections 4.2 Installation of the Hydraulic KIT 4.2.1 Safety inlet assembly It must be installed on the domestic hot water inlet before the water enters the tank. It consists of a pressure reducing valve, an expansion relief valve and a check valve, and connects the system to the expansion vessel. 4.2.4 Safety device connection T&P relief valve The factory-fitted temperature and pressure relief valve on top of the cylinder is a safety device that backs up the thermostatic control device(s) and non self-resetting energy cut-out(s). It works by sensing an excess water temperature or pressure and discharging the hot water. General structure 1 2 Possible T&P valve connection Discharge pipes from the temperature & pressure relief valve (T&P) and expansion relief valve may be joined together. For connection to the discharge line of the T&P pressure and relief valve, use the water connection (male, G ½”) located on the side of the indoor unit. 7 6 5 4 3 Fig. 47 Safety device assembly information Safety devices should discharge either directly or by way of a manifold via a short section of metal pipe (D1) to a tundish. The diameter of discharge pipe (D1) should be not less than the nominal outlet size of the safety device, e.g. temperature relief valve. Where a manifold is used, it should be sized to accept and discharge the total flow from the discharge pipes connected to it. The tundish should be arranged vertically in the same space as the non-vented hot water storage system, and should be fitted as close as possible to the safety device, in a lower position, with no more than 600 mm of pipe between the valve outlet (T&P) and the tundish. Do not install the tundish near electrical devices (see Fig. 47). 1 Expansion relief valve (set to 6 bar) 2 Service 3/4” pressure reducing cartridge and line strainer (set to 3.5 bar) 3 Cold mains water inlet (22 mm) 4 Balanced cold water take-off with non-return valve (22 mm) 5 3/4” BSP connection for expansion vessel 6 To cylinder (22 mm) 7 Expansion relief outlet to tundish (15 mm) If the Cold Water Balanced Takeoff is not used, a cap shall be installed. 4.2.2 Exspansion vessel The expansion vessel must be connected to the dedicated inlet on the safety inlet assembly. Check with your local water authority on what type of installation is acceptable in order to conform to the applicable building regulations and standards. 4.2.3 Tundish Installed in the discharge pipe after the valves, it provides an air break allowing the discharged flow to be safely conducted to the termination point. The tundish also provides a visible indication of the discharge and functions as backflow prevention device. To install it correctly, refer to paragraph Safety device connection. Discharges Any discharge should be visible at the tundish. In addition, where discharges from safety devices may not be evident, e.g. houses inhabited by people with impaired vision or mobility, it may be useful to install a suitable safety device to warn people when the discharge occurs, e.g. an electronically operated device. Connection of the discharge pipe (D2) to the tundish The discharge pipe (D2) arriving from the tundish should: – have a vertical pipe section at least 300 mm long below the tundish before any elbows or bends in the pipework (see Fig. 47); – be installed with a continuous fall of at least 1 in 200 thereafter. Examples of discharge arrangements The discharge pipe (D2) from the tundish should terminate in a safe place where there is no risk for people in the vicinity of the discharge. Below are some examples of acceptable discharge arrangements: – to a trapped gully with the end of the pipe below a fixed grating and above the water seal; – downward discharges at low level, i.e. up to 100 mm above external surfaces such as car parks, hard standings, grassed areas, etc. are acceptable, provided that a wire cage or similar guard is positioned to prevent contact, whilst maintaining visibility; EN / 29