Carolyn House - HIU Case Study

Altecnic Ensures Energy Efficient District Heating System for New London Apartments.

ARender Image of Carolyn House Project new apartment block that has been converted from offices will benefit from an energy-efficient district heating system thanks to 183 Heating Interface Units (HIUs) and more than 800 thermostatic radiator valves (TRVs) from Altecnic.

M&E contractors G&H Group worked closely with Altecnic to develop the specification for Carolyn House following its change of use from offices to an apartment block.  The specification and correct installation of the central heating system will save future residents money and also ensure that every apartment has a reliable source of hot water and heating even at times of peak demand.

Says David Davis, Group Director for G&H “District heating systems such as this are becoming more common and we were keen to work closely with a manufacturer who not only supply product but also provide technical advice and training so that we could provide an efficient and reliable solution.”

Achieving maximum efficiency from such a system relies on each apartment using as much energy from the hot water in the radiators as possible.  The return temperature of the hot water from the apartment to the HIU needs to be as low as possible.

The low heating demand in modern apartments means that only a very small flow rate of hot water is required on the heating circuit.  This low flow rate makes it difficult to balance the radiators, so there is a danger of the return temperature being high and transferred back into the network. This reduces the efficiency of the whole network.

Working closely with Altecnic, G&H maximised the difference in temperature between the ingoing and return temperatures from the heating, or Delta T.

First using the Dynamical TRVs from Altecnic, it is possible to finely balance the flow of water throughout an apartment’s heating circuit, so that each radiator maximises the surface area available for heating.

 

 

Second the SATK32103 HIUs are equipped with Return Temperature Limitation (RTL).  This allows a maximum return temperature to be set on the network.  Once enabled and set, the HIU will control its output into the apartment to ensure that the preset primary return temperature is met. Not only does this mean that each apartment is efficiently heated for minimum cost to each resident, but it ensures that the overall system does not fail due to small Delta T’s and high primary flow rates.

 

Continues Davis, “I know that other contractors have had problems with district heating systems in the past due to the nature of commissioning such systems.  We wanted to partner with a supplier that could work with us to develop the specification and provide product and training to ensure that the scheme is successfully commissioned.  Every resident in this apartment block will get heating and hot water on demand even at times of peak usage, such as on a Monday morning before people go to work.”

“Altecnic’s HIUs and TRVs and their level of technical advice and assistance have been invaluable in this very successful project.”