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puddleboy3
12-09-2007, 07:49 AM
Hello all, I have been carrying out work on a set of chillers that have not had any maintenance carried out on them. After sorting out all sorts of problems with the chillers it was time to tackle the water flow problem. (see attached photo)

Is there such a thing as an inhibitor that I could add to the system to try and break down the sludge or am I looking at replacing pipe work. 80% of the units in the building have either little or no flow.

Any suggestions would be much appreciated

George Rees
12-09-2007, 10:55 AM
Why don't you try dyno rods like what's used to clear blocked drains.

Electrocoolman
12-09-2007, 08:53 PM
How about using a central heating flushing unit? You can hire these. I believe KAMCO make a range that might be powerful enough to have an effect, and they have a tech dept etc. that might offer guidance.
You need to be able to break the system down into managable sections to get the flow rate.
Sounds a big job! Good luck.

Adrian.

frank
12-09-2007, 08:54 PM
I've never seen sludge that bad. As it's not actually build up on the pipe wall could it not be just flushed through?

The Viking
12-09-2007, 11:36 PM
OH Dear...

Only option is to get professional water treatment guys in.
Make sure you tell them that you want sectional power flushing (of all individual fancoils) followed by chemical cleaning, flushing and treatment.

But it ain't goin to be cheap..

Tesla
13-09-2007, 12:11 AM
Hi Puddleboy3
I agree with Viking. I've done one big chemical flush on chw system and think its best to let someone else deal with those nasty chemicals. We use and acid, then neutraliser, then inhibitor. I think some chw valves will be in a bad way too. It might be an idea to fix the problems and advise client to budget for a new system in the next few years. Looks like a lot of loose crap in system, would help to find the source and cause of it. Good luck

The Viking
13-09-2007, 02:09 AM
Tesla,
The source and cause of it is easy, unfortunately.
Here in UK the water supplied is crap for using in any processes, it's normally regarded as being between "hard" and "very hard". In some buildings they even use "water softeners" to reduce the hardness, these basically adds salt to the water... very rarely is the plant rooms on a separate supply so the chilled water system will have been filled with salt water with a high calcium content, you see where this is going?

To make matters worse, we have this habit of fitting "pressurisation units" (basically a small pump with a feeder tank fitted, these are necessary as the mains water supply's pressure is too low to fill a process system up) and then leave them permanently fitted and turned on (via pressure switches) just in case the system needs topping up.

BUT the real killer is the fact that our customers always are looking for ways to save money.
They can not see any ill effects of stop paying for water treatment, after all, it will take several years and the cost removed from several annual costings before the systems end up looking like the one above.

So, Bad water in together with original inhibitors, these are diluted by constant topping up of the system (and naturally degrades), then there are no monitoring of the water quality in the system or topping up of chemicals. Hey presto, you got a nice organic soup mixed with iron (from the pipes) and various other bits and bobs. Then the customer want to know why he has to spend soo much money to get it back up and running.


You think I answered this question before?
(I lost count on just how many times I had arguments about this with various customers)

puddleboy3
13-09-2007, 09:12 AM
Thanks for the replys, I have been speaking to various people and I was put on to a company called Fernox I spoke to there tech people and they advised me to add a solution called IC20. They say this will break down the sludge and allow us to flush it out after a few treatments.

ozairman
13-09-2007, 10:42 AM
If you guys got rid of the black iron pipe and hemp and compound you would probably be a lot better off to:p

I worked in the UK in the early 90's doing HVAC commissioning and on one system there were all these big HW coils in air handlers around the building with 1" and 1.5" pipes to them and way over on the far side the genius engineer had decided to hang a few small rads of the system with 1/2" iron pipe. Trying to do a water balance and SFA flow through the small rads, we take matters in our own hands and disconnect the rads and find a similar situation except it was just all the excess hemp and compound blocking them up!

The Viking
13-09-2007, 05:48 PM
Thanks for the replys, I have been speaking to various people and I was put on to a company called Fernox I spoke to there tech people and they advised me to add a solution called IC20. They say this will break down the sludge and allow us to flush it out after a few treatments.

Yes,
We tried that on a couple of jobs.

Doesn't work.

Proffessional water treatment people and sectional flushing.....

And the biggest bonus with that is that if it doesn't work, then to your customer it's the water treatment guy's fault.

;)

thornie
24-10-2009, 12:51 PM
Hello puddleboy3, When you come replace the pipework, which look imminent, could I suggest you consider plastics pipe as an alternative, eliviates many of these problems encountered with Iron pipes,and last a lifetime.

regards
Thornie

Brian_UK
24-10-2009, 08:22 PM
^^ Good plan but unfortunately three years too late. ;)