7 Nellmapius street

Duratherm Geysers

Duratherm Geysers (PTY) Ltd was started in 2017 in Chamdor, Krugersdorp South Africa and has grown to a staff compliment of more than 120 people. From the onset, the focus was on producing high quality water heaters (geysers), combining the latest available technology, with tried and tested features in an effort to


Accessories Duratherm Geysers (PTY) Ltd also stocks the following range of accessories for purchase: Draincock TP Valve Geyser Pack(DC +TP) Brass Bush Backnut + Adaptor Brackets Galv pipe for TP Valve discharge PRV + Relief Valve 15mm PRV +Relief Valve 22mm Vacuum Breaker 11" Thermostat 11" Thermostat Pocket 100L Drip Trays 150L Drip Trays 200L Drip Trays 250L Drip Trays 300L Drip Trays Nova Sun Solar Systems


DIRECT SYSTEM In a direct solar system, the water is heated by circulating water from the storage vessel through the solar panels. This can be done naturally via thermo-syphon or by a pump. The system is simple and cost effective however it must be noted that the pressure in the storage cylinder will be transferred to the panel which makes this unsuitable for some panels. Should this system be selected in areas of consistently low temperatures (-0°C) in winter i.e. Sutherland and mountainous areas such as Drakensburg, Maluti and other cold areas, there are simple ways in controlled systems to stop panel freeze. In coastal regions and most other parts of South Africa, direct systems are highly suitable without the need for freeze control. Whether or not a panel freezes also depends to a large degree on the panel quality i.e. insulation, air gap etc. Furthermore, the integrity of the installation, the insulation of the pipes – particularly copper pipes etc. could be responsible for the system freezing. A direct system should not be installed in areas where the water contains high levels of dissolved solids. Depending on the severity of the problem the panel could get blocked up in a short period of time, rendering the whole system ineffective. In a direct system the geyser has no influence on the performance of the system, other than the temperature provided by the electric element as a back-up, since it functions purely as a hot water storage tank. Specifications for direct tanks INDIRECT SYSTEM Indirect systems are more complex in that apart from all the other components, there is a heat exchanger, either as a sleeve on the outside of the tank or a suitable, mostly copper or stainless steel apparatus inside the tank to transfer temperature from the panel to the water inside the geyser. Panel size / performance must be matched to the capacity of the storage tank in such a way that the system works efficiently. In all the tests done at the SABS by various solar companies who elected to have their systems tested in conjunction with a Solartherm® geyser, test results show high to very high efficiency levels. The efficiency levels are expressed as a "Q" factor and represent the basis on which the Eskom rebate system is calculated. W.E. Geysers produce 2 types of indirect geysers, the "Standard" type heat exchanger, and the "Trumpet" type heat exchanger. In both cases the heat exchangers can be replaced or repaired in the event of future failure. The "Standard" type geyser was designed to accommodate passive (Thermosyphon) and active (Pumped) operation. The "Trumpet" type geyser was designed for active (Pumped) operation only. Both systems find their uses and acceptance in the market place and offer the customer various options. Indirect system heat exchangers are filled with a food grade glycol (anti-freeze) solution, which therefore prevents the panel from freezing up or blocking, and increases the boiling temperature of the transfer fluid. By being able to select a glycol mix as transfer fluid, the problem of lime and/or other build-up is also prevented. The installation of active indirect systems, as well as their maintenance is more involved than passive indirect systems or active / passive direct systems. The glycol mixture should be replaced at least every three years. Specifications for indirect tanks Solartherm - Geysers - Direct System Solartherm - Geysers - Direct System PUMPS Active indirect systems can be circulated by either a 220/230 Volt pump, or a 12V pump operate via PV (Photovoltaic) panel. During the day the PV panel acts as a battery charger. The battery in turn operates the pump and supplies power to the system controller. Indirect systems are more expensive than direct systems and active systems are more expensive than passive systems.


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