Optimum water temperature?

[bobg]

I invested in one of HPC's excellent chiller units for my 3020. Works a treat (I can laser all day with no increase in water temperature) and is quiet. I have the chiller set to 18c. Usually the room is slightly warmer than this so when I turn it on it has to work to take the water temp down to 18. What's the optimum temperature for efficient operation and long laser life?

Bob

[PhillyDee]

Im after one, but they are out of stock. No idea when they are getting them back in either. I really need one for productivity.

Spooky has a post somewhere about it, think he runs his about 10 degrees below ambient.

[Spooky]

10 below ambient or 8 degrees actual temp

[bobg]

Thanks - sorry I missed the earlier post about temp. Heck 8c is cool. I'll try it but I guess it will take the unit 30 minutes or so in my room to get down to that sort of temperature. That's a looooong time to wait before lasering.

Bob

[tweakie]

Chillers can cause their own problems and you may want to consider the risk of damage to your laser tube and any possible warranty considerations when taking the temperature of the cooling fluid below the ambient temperature without due regard to other factors.
Today, for example, it is raining and most of the UK is experiencing a relative humidity of around 95% and this means that the dew point is only a few degrees below the ambient temp. Cooling the tube to below the dew point will cause condensation to form and if this forms on the surface of the output coupler disaster could soon follow.
It is a general rule that the chillers temperature is always set to a point above the prevailing dew point to prevent condensation forming on the optics as well as the electronics.

Do HPC make any temperature recommendations for using their chillers with their lasers ?

Tweakie.

[PhillyDee]

Wise words! We work with the same theory on telescopes. When its cold outside, dew settles, this makes the optics unuseable. So we cover them with dew bands, on the outside. The idea is to keep the temperature just 1 degree above the dew point, as any more can cause thermal currents, and this ruins the view. Of course, it would not kill the optics, but it does put a stop to the nights viewing pleasure.

[bobg]

The Chiller was supplied showing 18c - so I left it at that. Chris made no comment about changing the temperature or indeed, a recommended temperature. As the room is normally about 20-21c the chiller works for a few minutes when turned on to reduce the stored water to 18c. As everything seems to be working OK perhaps I should just continue 'as is'?

Isn't this Forum just great! Thanks for your various commments.

Bob

[Spooky]

"If it aint busted, don't fix it" my ole dad used to say

[Spooky]

8 degrees will give the highest power / perfomance ratio but as the guys say condense can be an issue. It's all to do with the resistance of CO2 gas mixture, below 8 degrees you start losing power ,same for above.
My day starts at 8 degrees and ends up 8 hours later at around 14 degrees.if I started higher I'd end up higher and lose productivity.Thankfully of late its mostly test cuts for plans so I don't have so many temp problems

best wishes

Dave

[Matrix]

Hi All,
Just invested in an HPC chiller unit, as we need our 6090PRO running all hours and fast as possible to keep up with orders (nice problem to have!)

Chiller set point is 17deg, but after only a hour or so's use, still getting 24-26deg readout for the coolant temperature.
Just a silly error (plumbing wrong?), poor coolant flow within the machine (14month old tube), or are we just expecting too much and pushing the machine too hard? I'm not quite sure (don't have any idea how hot we were running 'pre-cooler' for comparison.)

We'd really appreciate any advice - still a bit paranoid that we are on the 'schoolboy errors' bit of the learning curve!