EBME Forums Forums Maintenance Technical Assistance Asena GW

I have a number of these nice little volumetric pumps (the GW, that is) that come up with the dreaded (by me, at least) Bad Set error after about 15 seconds of pumping. Does anyone have any nous regarding this?

Does anybody have details about what is actually going on at this stage? The pump is presumably testing the compliance of the giving set, or some such thing, before either rejecting it as a "Bad Set" or accepting it for delivery to continue. The manual claims that this also guards against simple reversal of the direction of the set (that is, being installed the wrong way around)!

It looks to me like the pump starts off pulling in reverse for a few seconds, and then proceeds in the pumping direction. It is a few seconds after this that (on the faulty pumps) the "Bad Set" error makes itself known, and pumping action halts. I am assuming that some sort of cleverness involving the pressure sensor is involved.

I believe I have got the pressure cal accepted, and the "null pressure" is correctly adjusted via R2 on the Pressure Sensor Board. So it looks like replacement of the Pressure Sensor Board(s) is on the cards. Or am I missing something here (something not mentioned in the manual, perhaps)? Like an "undocumented" code that needs to be accessed, and tweaked, for instance?

I believe I may have cracked this one.

It turns out that the GW's are not faulty at all (well, not in this regard, at least). Indeed, if there is any fault here then it really lies with the operator (or, in this case, the tester), I’m afraid.

It seems that the giving set needs to be properly and fully primed before attempting to run (test) the pump. Both upstream and downstream conditions need to be right when the mechanism "pulls back" during start up, as this is indeed when the pump checks for a "Bad Set".

It is worth stating also (and obviously, perhaps) that the correct giving set needs to be used (and a fresh one at that). It also seems a bit fussy about the 300 mm or so head height (distance of the bag above the pump) as well. In short, the test has to be properly set up.

I have found that running the Volumetric Accuracy Verification test (Code 5) described in the manual ensures that all is well before embarking on a final test using the pump analyser (IDA et al).

Sometimes (often, in fact) persistence pays off!

Hi, Geoff !
I'm looking for service manual on the Asena GW. I want to ask you - could you solve the problem with "bad set" ?
Best regards - Michael.

Hello Mikhail.

I haven't touched a GW in over eight months, unfortunately (or should that be:- fortunately) ... and I never did crack this one to my satisfaction.

If anyone has a secret list of the access codes for this little pump, I would be very interested in taking a look at it (purely from an academic interest point of view, of course)!

Meanwhile Frank has the manual.

But for completeness, let's link ... and link again!

Hello Geoff !
Thank you very much, I will try to solve this problem!