Manual FlexTherm Eco
5
1. Introduction
The FlexTherm Eco range of advanced and compact heat storage use the Phase Change Materials (PCMs) to store heat for producing hot water
and for space heating in buildings. Flamco heat storage can be classified as primary thermal because the hot water is heated instantaneously
on demand by transferring heat from the PCM to the mains water flowing through it, and they function like buffer vessels for space heating
applications.
The pipe connections and the construction of a FlexTherm Eco range of storage are shown in figure above. The phase change material (PCM)
and the heat exchangers are housed in a sealed enclosure called ‘The Cell’. Although the Cell is sealed, the pressure inside the Cell is around
the ambient atmospheric pressure i.e. about 1.0 bar absolute. The Cell is insulated using highly efficient vacuum insulation panels. The outer
case and hydraulic and electrical connections are designed so that multiple storage can either be stacked or positioned side by side and then
connected either in series or parallel.
The FlexTherm Eco range of heat storage have two independent hydraulic circuits and either or both can be used for charging or discharging
the heat storage. The heat is transferred between the PCM and the high power (HPC) and the low power (LPC) hydronic circuits by means of an
integrated heat exchanger inside the Cell.
The heat storage are fitted with temperature sensors for measuring the charge state and for controlling their operation when connected to the
controller. All standard models of the FlexTherm Eco range of heat storage are supplied with PCM58 which has a phase transition temperature
of 58 °C.
The heat storage models covered by this document are listed in table 1.1. This document does not complete cover sizing, selection,
configuration or design of the heating and hot water system in a building. It only covers installation and commissioning of the selected compact
heat storage and a few examples of different applications.
Table 1.1: FlexTherm Eco Range of heat storage
Generic range
Description
Models
FlexTherm Eco E
These heat storage are heated by internal electric heating
elements only and therefore these heat storage are equivalent to
Direct vented or unvented hot water cylinders
FlexTherm Eco E3, FlexTherm Eco E6, FlexTherm
Eco E9
1.1 Advantages of FlexTherm Eco compact heat storage
1.1.1 FlexTherm Eco
The main benefits of the FlexTherm Eco, compact heat storage, compared with the traditional hot water cylinders and hot water only thermal
stores are:
a.
The heat is stored in the Phase Change Material and therefore the stored water content in the storage is less than 11 Litres
and the hot water is heated instantaneously on demand. Therefore:
•
Easy installation because of low expansion volume.
•
The risks of legionella are significantly reduced.
b.
Quicker and less costly installation.
c.
No mandatory annual maintenance or inspection is required and therefore lower running costs.
d.
Operational needs: Smaller space, typically 2 – 3 times smaller than the equivalent hot water cylinders and clean installation.
