Simply Koi and More Koi

i have a filtertech digistat and its started flashing three dashes across screen, just wandered if anyone had an idea what it is?

cheers

tom

Tom,

I don't know this particular stat but, in general, when electronic stats receive a signal that is out of their measuring range they put a warning on the display.

That will happen if the temperature they are measuring is way below freezing or way above 40 C, but in this case the most likely cause is that the signal is out of range because either the probe is disconnected or water has got into it and short circuited it.

Check that the probe wiring hasn't been pulled out of the connector strip. If it hasn't, the manufacturer's helpline will confirm whether a new probe will solve the problem.

cheers sid, ive swapped probes, also phoned manufacturer and they have been bought out by another company so the company knows nothing about them. im going to see if any moisture has got in and go from them

tom

Tom;

If you get an answer can you let me know. I have two of these and they are normally very reliable.

Cheers

Peter

Tom,

You say you've swapped probes, did you swap the suspect one and the display stayed the same? If so, then either your new probe has an identical fault, which is extremely unlikely if it's a new probe, or the disconnection is just inside the stat electronics, possibly where the connector strip solders onto the printed circuit board. That's always a vulnerable point.

Hey guys and girls;

While we are on the subject of failure of electrical thermostatic control systems as Manke said the commonest cause, IMO is water getting into the thermistor. The sensors seems to be meant for air and then protected against water by using heat shrink rubber sleeving so it’s no surprise they fail after a time constantly immersed in water. So two question;

1) What should we do to further waterproof our temp sensors? I have epoxyed one of mine in a larger diam plastic tube it delays the response to temp changes but has stood the test of time.

2) Is there a maker of sensors compatible with our systems (and most suppliers will tell you the resistance range they need for units to work) that we could use in place of the ones normally supplied with the units?

Peter

will do brockp if i get it sorted. cheers sid, the probe i used came of my mates and was working fine. there must be a loose connection somewhere then, im gonna let it dry for a day just in case and go from there, im no good with electronics

tom

Tom,

If you tried his probe with your stat and there was no change, that suggest a fault in the stat itself but the final proof would be to try your probe with his stat. That will confirm whether the probe works or has water in it. This is looking like one of those rare cases where it isn't the probe but a fault in the stat electronics.

Hi Tom,

hope you have it all under control now and here are some instructions just in case you don't have any:


http://www.koicarp.net/electrical_heati ... tting.html

i think it is looking like that, cheers for all the advice tho

tom

Hi Tom

Could be a dry joint on the board with one of the components this could cause this issue, I'm in the electronic industry and come across them all the time. May even be corrosion on one of the solder tracks.
Found a web site that may be worth a go.
Try http://www.altaquatics.co.uk they have spares for these units apparently when the company closed they have the sole rights to any parts and may well have heard of this fault before there telephone number is 01925639333.

Good luck with it.

cheers dave, this is who ive spoke to, they want me to send the unit in, they will send it to the original manufacturer then get me a price to get it fixed. im just wandering by the time ive posted it and paid for repair i might be better off buying a new one. was just hoping it might be a simple fix

tom

Hi Tom,

I reckon you already know but your probably best to buy a new one and save on the time messing about.

Have you turned it off to see if it will re-set

yeah mate, ive left if off for a day to see if it needed drying. ill try it again tomorrow if it dont work it will go in the bin

tom

Probably say Gazza is right there by the time you send it back and mess around if you add it all up it will be cheaper to get a new one.
Let's face it you could get it repaired and they will probably offer a guarantee of around three months and it's sods law it will go wrong again.

At least with a new one you can rest knowing you have a reliable unit and a long guarantee.