E4800 Recirculating Heater/Chillers

The E4800 Series of Recirculating Heaters/Chillers are recommended for a wide range of open and closed-loop temperature control applications. The E4860 is an option for the E3100 and K850MW critical point dryers. For applications requiring heating only the E3500 Thermocirculator is recommended.

Key features

• Precise temperature control
• Quiet, efficient operation
• Proven reliability
• E4860 recommended for use with the E3100 critical point dryer

Product description

Environmental considerations

Increasing pressures on natural resources have resulted in many countries restricting the use of water run to waste for cooling of instrumentation. The E4800 series can be used in locations where mains water is not available. Corrosion in closed systems can also be minimised by adding inhibitors and, with suitable additives, temperatures below zero can be maintained. A three-term digital temperature controller ensures ease of use and accuracy.

Temperature control

Many instruments measuring physical properties depend on accurate control of temperature and in some processes optimum temperature is essential. With the E4800 series, over-cooling (which affects efficiency) is prevented and the water temperature can be accurately controlled over the range -10º to +60°C.

A commonly misunderstood feature of refrigerated systems is in applications where the control temperature is other than at or near room temperature. When the instruments are to be operated at controlled temperatures below ambient, the extraction deteriorates significantly and, as a guide, the compounded change is 4% per degree Celsius. In practice, the refrigerant gas pressure has to be adjusted to optimise the performance at any particular temperature. However, the E4800 series incorporate automatic adjustment valves in the systems.

Closed loop

The E4800 series are of the ‘closed loop’ type and therefore efficiencies are dramatically improved compared with open bath models. The E4800 series are simple to set up and to operate and essentially maintenance free.

Choosing the correct heater/chiller

In order to optimise performance from a heater/chiller system, the correct specification must be selected for a particular application. To cool or heat any instrument or system it is important to obtain the following information from the manufacturer:

* Heat load to be dissipated to water, e.g. for an electron microscope lenses

* Flow rate and size of tubing

* Minimum pressure

With this information, consult the table below and select the appropriate heater/chiller. The basic heat load calculation formula is as follows: flow rate x weight of fluid x specific heat x D T = Heat Extraction.

Heat extraction rates (in Watts)
	-20ºC	-10ºC	0	10ºC	20ºC
E4860	75	105	180	300	420
E4870	125	250	500	900	1200
E4880	200	425	700	1600	2200
E4890	350	600	1200	2000	3000

For use with the Quorum E3100 and K850WM critical point dryers

The E4860 is a recommend option with the E3100 and must be ordered with the K850WM wafer dryer.