Clean pH pen, Hach pocket pro

[renthispace]

I'm getting ---- and drifting pH on the readout of my pH pen. I contacted Hach and they said to clean it. What's the ideal cleaner? I have phosphoric acid for mash pH adjustments...or is this a protein fowling?

I've used this pen about 10 times since I got it a year ago, always rinsed with distilled water (I don't have di access) and stored in storage solution. Is this on par with normal maintenance?

 

[brick_haus]

It might be advisable to take this question to the brew science category on this forum. Tons of knowledgable people there.

 

[LandoLincoln]

The manual says:

For grease, oils and fats - Use an electrode cleaning solution - 2 hours maximum
For mineral buildup - 10% hydrochloric acid solution - 5 minutes maximum

Hmm...is wort a grease/oil/fat? I'd say no. I think the problem would be mineral buildup. Beer stone kinda problem, ya know?

And by the way...I don't know if it's a good idea to store it in a storage solution. The instructions don't tell you to do that. It says, "Before the initial calibration and after a dry storage, soak the sensor for several minutes in the sample or tap water [before calibration]." The manual makes no reference to any kind of storage solution.

 

[renthispace]

Thanks for the input, I know there were lots of questions regarding storage. Common practice with pH probes is to not store them dry. Maybe this unit isn't like the rest...

And it does look like brew science may have been the better area to post this, any mods willing to move this thread?

 

[ajdelange]

Clean it with an enzyme based cleaner such as Zymit. Zymit comes through laboratory supply houses and is, therefore, expensive. There are enzyme based cleaners available elsewhere i.e. at supermarkets. I just don't know the names of any of these products.

 

[IslandLizard]

Thanks for the input, I know there were lots of questions regarding storage. Common practice with pH probes is to not store them dry. Maybe this unit isn't like the rest...

And it does look like brew science may have been the better area to post this, any mods willing to move this thread?

IIRC, a couple drops of water in the storage cap is all that's needed, so it won't dry out.

You need to report the thread (click on red triangle) and ask to move to the Brew Science forum.

 

[trentm]

I'm getting ---- and drifting pH on the readout of my pH pen. I contacted Hach and they said to clean it. What's the ideal cleaner? I have phosphoric acid for mash pH adjustments...or is this a protein fowling?

I've used this pen about 10 times since I got it a year ago, always rinsed with distilled water (I don't have di access) and stored in storage solution. Is this on par with normal maintenance?

Following. For what it's worth, I had a similar problem with a Milwaukee 102 (drifting). My gut said the probe was faulty but before purchasing a new probe, I did a little research and found Milwaukee has a cleaning solution. With little information on how to use it, I dreamed up an extreme method: ~30 ml of the cleaning solution was added to a 50 ml erlenmeyer flask with a stir bar. Then the probe was submerged just under the liquid level but well above the stir bar and secured. The flask was placed on a stir plate set to a speed that just kept the solution in motion and left overnight. Results: The meter is now working great.

 

[renthispace]

What kind of solution was it? Do you have a link?

 

[trentm]

What kind of solution was it? Do you have a link?

http://cynmar.com/ProductDetail/24075463_Electrode-Cleaning-Soltn-General230ml--Milwaukee-Ma9016

It is usually advised to use products made by the company that makes the meter.

Here's a link to the Hach brand cleaning solution (seems pricey). Also, under the "downloads" tab you can find some cleaning and maintenance instructions.http://www.hach.com/electrode-cleaning-solution/product-downloads?id=7640205099

 

[ajdelange]

Ordinarily I'd agree with that sentiment but here you want to be sure the cleaner is enzyme based as it is proteins and sugars gumming up your junction and coating your bulb. Now if the manufacturer has an enzyme cleaner....

 

[renthispace]

Figured I would post a follow up. Hach responded with a few things to try (replace batteries just to be sure) and that phosphoric acid could substitute HCL. I'll try those first but I also got the link for their version of protein cleaner.

http://www.hach.com/probe-cleaning-...ins-500-ml/product?id=22245361961&callback=qs

Pretty expensive! Almost half the cost of the meter. I still feel like my meter is new and shouldn't be having this issue for the amount that I use it (or of this really was an issue then fellow brewers would have this enzyme cleaner right next to their calibration solution, which I don't believe is the case).

 

[Gavin C]

This is what I use for my Hach pro+

I clean it before and after using it each brewday

 

[renthispace]

Thanks Gavin, for that price I'll probably pick some up and copy your usage practice.

 

[Gavin C]

Thanks Gavin, for that price I'll probably pick some up and copy your usage practice.

No worries. Hope it works well for you.

 

[renthispace]

Well the follow up to this problem is here. I brewed some beer over the weekend and finally busted my pH pen out to try again. Got it calibrated but the moment it went into beer I got the funny count down and then the dreaded ----. I tried soaking in phosphoric acid, and the general cleaning solution but nothing brought it back. So I contacted Hach customer support again.

This time since I had ran through their proposed solutions, they concluded I needed a new sensor. Of course its out of warranty...I figured they may be flexible since I barely use this thing (15 times in a 12 month period). But I get no love from Hach, they say the normal life span of a sensor is 6-12 months "We expect that these sensors last 6-12 months depending on use". Wish that was on their site, probably would have went with a company with cheaper replacements like Omega.

Is this really correct? pH sensors need to be replaced this often with such light use? Any other Hach PocketPro+ users have problems with premature sensor death? I'm contemplating purchasing the http://www.omega.com/pptst/PHH-7000.html because it is only slightly more than Hach's replacement sensor. I'm pissed that I paid MORE to go with Hach for the name brand thinking they would have better customer service in situations like this. I was proved wrong, should have saved the money and went with someone else. Especially since they claim these sensors fail after a year! Where is that information on their product page?

 

[LandoLincoln]

Well...in my very limited experience with pH meters...they're all quite fragile creatures and sensors don't last very long. Which is why I'd never buy another pH meter that didn't have a replaceable sensor. Unlike all of our other brewing equipment that will last quite a long time...reading pH accurately is an expensive endeavor, apparently.

 

[renthispace]

And another follow up, I got a call from their tech department and they are going to replace my probe.

Apparently the PocketPro+ is not like other meters and must NOT be stored in storage solution. Their documentation omits this fact (it doesn't say anything in regards to storage--I figured they missed this and it needed to be in storage solution like other probes).

The technician believes that my probe died so early because it was stored in storage solution. He's putting in a request to update the documentation to include the fact that it should not be in anything. He mentioned that it should be stored moist--as in leave a drop or two of water (DI or otherwise, just to provide humidity) in the sample cup and that it should not be submerged.

 

[Gavin C]

And another follow up, I got a call from their tech department and they are going to replace my probe.

Apparently the PocketPro+ is not like other meters and must NOT be stored in storage solution. Their documentation omits this fact (it doesn't say anything in regards to storage--I figured they missed this and it needed to be in storage solution like other probes).

The technician believes that my probe died so early because it was stored in storage solution. He's putting in a request to update the documentation to include the fact that it should not be in anything. He mentioned that it should be stored moist--as in leave a drop or two of water (DI or otherwise, just to provide humidity) in the sample cup and that it should not be submerged.

That's great that they are going to replace it and update the manual.

The Hach Pro+ is definitely the oddball when it comes to storage it would seem. Thankfully I found that out early on after storing mine in it for a week or so.

Nothing in the manual about storage so I like many assumed storage solution was needed.

Ever since I do exactly what you describe. After cleaning, place a few drops of tap water in the cap and seal it.

Touch wood, no problems yet.

 

[ajdelange]

The technician believes that my probe died so early because it was stored in storage solution. He's putting in a request to update the documentation to include the fact that it should not be in anything. He mentioned that it should be stored moist--as in leave a drop or two of water (DI or otherwise, just to provide humidity) in the sample cup and that it should not be submerged.

Quite possible. I was able to confirm (by chatting with the Hach reps at MBAA Jacksonville) that they did have the suspected rollout problems that many observed here and passed on that their better than typical customer support was appreciated. I think that they must be selling a lot of these to brewers as they now offer a kit for brewers which includes this meter (and a copy of John's book - he didn't know about this).

I expect the storage solution problem relates to a novel reference junction design (I've never seen anything like it before).

 

[mabrungard]

I expect the storage solution problem relates to a novel reference junction design (I've never seen anything like it before).

AJ, I'm assuming that their junction is not employing the typical KCl electrolyte? That would easily explain why storage solution doesn't work on that instrument.

As you properly chided me about: "Store a pH probe as recommended by the manufacturer." Since Hach has very skilled technical personnel, their advice is valid. Other equipment resellers may not always have good or valid advice. Be careful and buy good equipment. As AJ points out something like this: The luster of low price is diminished by low quality. Buy decent equipment and you are more likely to be satisfied.

 

[ajdelange]

AJ, I'm assuming that their junction is not employing the typical KCl electrolyte? That would easily explain why storage solution doesn't work on that instrument.

That's what I am assuming too.

As you properly chided me about: "Store a pH probe as recommended by the manufacturer." Since Hach has very skilled technical personnel, their advice is valid.

The original manual was, as noted, silent about this and people reported over the past year getting conflicting advice from tech support with at least one confession that they didn't really know.

 

[timsch]

I have the HACH PocketPro Plus. It is about 15 months old, and I've used it about 6 times. I'm getting what I assume is drift. I put it in the calibration solution and it will slowly drop over the course of 20-30 minutes about .5. Yesterday, the calibration for 7.0 started around 7.26 and ended at 6.75. I exited the calibration and then calibrated the 4.0 solution. Saved and then measured the 7.0 solution. It dropped and stabilized at 6.83.

I've never cleaned it, so assume that is the problem. Let me know if that is not the case.

I have always stored it with a couple of drops of RO water in the cap. I use it only for homebrewing.

I've seen recommendations in this and other threads to get the manufacturer's cleaning solution. Looking at the Hach site, I get this, but it has a picture of several different solutions, and reading the Hach pH ELECTRODE CLEANING & MAINTENANCE GUIDE hasn't set off lightbulbs above my head either about what exactly to get for cleaning. AJ has stressed getting an enzymatic cleaner, but I've not seen anything with that description on the Hach info.

I need to order something. Anyone have specific recommendations? I saw one recommendation for this, but I don't know if this is optimum. Not that I need optimum - sufficient would be acceptable.

 

[ajdelange]

I wish I could assure you that cleaning is all you need but I can't. We know quite a bit about this meter and its electrode but we don't know what is a reasonable life time expectation for it. I assume it has been stored with a couple of drops of water in the cap which water does not touch either the membrane (glass bulb) or reference.

A good cleaning is always the first thing to try and, where the application is brewing, an enzyme cleaner is indeed a good idea. I always use Zymit a liter of which you (or you and 5 or more friends) can get from Cole-Parmer for $35. I mention the five friends because the liter will make from 50 to 100 Litres of working strength solution.

Try cleaning a couple of times if a single go doesn't fix your problem. No amount if cleaning will fix the drift/response then it is possible that the electrode is at end of life. For a modern electrode you should get, on average, about 2 years I'd say. Some electrodes last longer than this (I've got one that is, I think, at about 6 years now). And other last for less time than this. You may be unlucky and have a short timer. In this case you can, if you wish, buy a replacement electrode. The bad news here is that in these inexpensive meters the electrode is often responsible for 70 - 80% of the meters' costs.

 

[timsch]

So is the electrode life time dependent regardless of usage? Is there anything that can be done other than cleaning and proper storage to maximize the life, i.e. is it better to use it weekly or monthly rather than every two or three months?

I see that the Zymit shelf life is two years. I'd use maybe 1-2% of that liter. I wish I could say I had a HB group to share with, but no such luck. I'll still get it if there are no other options.

It'd be nice if there were a powder enzymatic cleaner for these meters. I see products like this and wonder about their suitability. I don't see info on its shelf life, so it may be no better.

I really want to monitor my pH levels, but it'll be a bitter pill to swallow at nearly $20 a brew session to do so as it stands now.

 

[ajdelange]

So is the electrode life time dependent regardless of usage?

Use is a factor. Every time you use it some electrolyte flows out of the junction into the sample. But of course there is no way that 5 brews should exhaust the reference electrolyte.

Is there anything that can be done other than cleaning and proper storage to maximize the life, i.e. is it better to use it weekly or monthly rather than every two or three months?

Proper use, especially avoiding sharp temperature changes, help to prolong the life. Proper storage does too. For example with this particular electrode evidently storage in the almost universally standard saturated KCl solution will destroy it.

I see that the Zymit shelf life is two years. I'd use maybe 1-2% of that liter. I wish I could say I had a HB group to share with, but no such luck. I'll still get it if there are no other options.

I'd double that shelf life. You won't have the full strength stuff at end of 4 yrs but I don't thin it will be rendered ineffective by then either. Still rather dear though!

It'd be nice if there were a powder enzymatic cleaner for these meters. I see products like this and wonder about their suitability. I don't see info on its shelf life, so it may be no better.

Martin B. has identified some product or products which are suitable. Perhaps he will see this and comment.

I really want to monitor my pH levels, but it'll be a bitter pill to swallow at nearly $20 a brew session to do so as it stands now.

Guess you'll just have to brew more!

If I toted it all up I'm betting I'd find my homebrew costs me hundreds of $ a glass.

 

[timsch]

Guess you'll just have to brew more!

If I toted it all up I'm betting I'd find my homebrew costs me hundreds of $ a glass.

LOL! True enough. That's the simple answer. I don't think I need to drink more though. I'm good with my pint in the evening.

Too bad I've not yet got to the point of actually liking to brew, even 10 years into it. If I did I'd just consider it an entertainment expense. I sure do love the end product, though. Still, I strive for efficiency (others call it cheap) and it's so deep in my bones that it's almost a curse.

 

[timsch]

I got the Zymit Pro cleaner and made a 2% solution.

I read others putting their meters into a solution on a stir plate. seems like a good idea, but what do I know?

How should I use this solution? Submerge the electrode, or spray it? How long on the exposure?

 

[ajdelange]

The solution should be warm (not hot - dunking the electrode into hot Zymit solution is as bad as dunking it in hot wort from the thermal stress POV). I'd let it soak a few minutes, stir for a bit, then let it soak again and repeat that cycle a few times. Then rinse thoroughly with warm tap water, rinse off the tap water with DI water and try to cal again. If you can't then repeat the Zymit process. What do you have to lose? If you don't see any change then it is probable that the electrode is at end of life for whatever reason. Hach admits that they had electrode troubles in the early release of this product.