Mandatory plumbing components for all Sunamp Thermino and UniQ heat batteries

Heat Battery isolation valve

MUST be fitted to enable safe and adequate heat battery maintenance (if required). Do NOT install this between the heat battery and expansion vessel or ERV. Please refer to the hydraulic diagrams in the product user manual for more information.

Mains cold water pressure reducing valve (PRV)

The maximum rating of the valve MUST not exceed the maximum operating pressure of the heat battery.

Mains expansion relief valve (ERV)

The maximum rating of the ERV MUST be no higher than 8 Bar. The operation of the component must be checked and deemed satisfactory in accordance with the manufacturer’s maintenance instructions, and preferably coincide with the expansion vessel maintenance intervals. The ERV can be located away from the heat battery provided there are no check valves between the ERV and the heat battery. The ERV must be discharged in accordance with existing local codes and regulations.

Expansion vessel/shock arrestor

Charge pressure of the expansion vessel/shock arrestor MUST be equal to the mains incoming pressure. A minimum of 0.5L expansion vessel/shock arrestor is required (please follow the correct calculation methodology for sizing EVs). The charge pressure must be checked and topped up in accordance with the expansion vessel/shock arrestor manufacturer’s instructions for maintenance, or annually, whichever is sooner.

Hot water thermostatic mixing valve

MUST be fitted and regulated to provide hot water output ranging between 45°C and 55°C.

Water conditioner

MUST be installed in areas where water hardness can exceed 150ppm

Thermino and UniQ indirect models only

Auto-bypass valve

MUST be regulated to meet flow rate requirements and the heat pump’s defrost minimum flow rate and volume requirements (if external heat source has an integrated auto-bypass valve, do not install another!). Can be omitted if:
(i) heat source does not exceed the maximum recommended flow rate of the heat battery in any operational mode,
(ii) there is sufficient system volume to allow defrost operation of the heat source,
(iii) heat source does not use the heat battery for defrost, and
(iv) heat source is a GSHP or a Boiler.

Expansion vessel (primary circuit)

The external heat source circuit (closed circuit) MUST be fitted with a suitably sized EV such that there is an unobstructed pathway between heat battery ports B&C and the expansion vessel. Please refer to external heat source manufacturer’s guidelines for suitably sized expansion vessels. NOTE: if the heat battery is isolated from the expansion vessel, then an additional expansion relief valve MUST be fitted between the heat battery and its isolation point to avoid overpressure forming in a closed circuit! Please refer to the heat source manufacturer’s instructions for suitably rated expansion relief valves.