inexpensive, trouble-free gel drying pump

[leidich at mbcl.rutgers.edu]

	For those of you still using a vane (oil-filled) vacuum pump and 
refrigeration dryer for gel drying I should like to make you aware of a very
good pump for doing just that without the messy oil and without the 
refrigeration dryer.  A diaphragm pump seems to be a good solution to the 
maintenance problems.  It is essentially a fish tank air pump but is more
powerful and, in fact, has two stages.  
	We see a lot of problems with the refrigeration traps and the 
emulsification of the pump oil as the water sneaks through trap into the pump.
The diaphragm pump is about 1/2 the price of a new oil/vane pump and no trap
is necessary.  The best pumps have teflon coated diaphragms which last 
about 10,000 hours and almost anyone can change the diaphragms if they fail.
They are not very costly.  
	While there are several companies selling these pumps we have found 
one that is far better than most.  The company is called Hovac and they 
sell a pump manufactured by Nueberger.  I believer Neuberger is the best
pump available.  Hovac is very service oreiented and, as a result, has made 
modifications to the pump which make it very easy to use in the bio labs.
	The cost of the pump is approximately $700 and will be supplied
with an inlet fitting to match your system.  We have used them on gel dryers,
vacuum ovens, and microfuges with great success.  

The pump is small, quiet, and almost fool-proof.  It has an automatic venting
system that opens a vent valve when the pump is shut off so the pump will
not be damaged by stressful start-up.  The liquids condense on their way
through the pump and are trapped in a container at the exhaust port. (you
must supply your own container)

Hovac
Fax (215)355-5365

Phone (215)355-7061

63 Frog Hollow Rd.
Churchville, PA 18966