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Lowrider
21-04-2007, 11:07 PM
A customer of us has three chillers with brazed plate heatexchangers from an undisclosed company along with a few of ours. From one of the three chillers the evaporator has blown due to frost.

The supplier says they can deliver a new one by the end of July, machine went down last week!

Both compressors contain more water then oil so they also need to be replaced! They cost almost the same as 3/4 of a complete machine and can be delivered within 16 weeks from ordering!

Is this common?:confused:

We desided to use our one evaporator which is slightly larger in size, costs half and was delivered within 2 days.

Howcome a large company in chillers can't deliver an evaporator within the week?:(

Dan
22-04-2007, 02:09 AM
Both compressors contain more water then oil so they also need to be replaced! They cost almost the same as 3/4 of a complete machine and can be delivered within 16 weeks from ordering!

I had a situation where the compressors had more water than oil, yet one of the compressors survived. We didn't simply condemn the compressors because they were contaminated.

The crazy part of my problem was that it was a shell and tube heat exchanger, and after revisiting the disaster, the problem was a blown diaphragm in the discharge pressure regulating valve.

Plate through plate ruptures on Brazed plate evaporators I find quite rare. Also, like you, I was able to get my replacement heat exchanger within 4 days, because I studied what was available and chose something that was in stock. Don't get stuck with having to replace "like for like" when you have a customer who is losing money as a result.

You did right by getting what was available. I just hope you didn't have a water regulating valve fail, as was the case after forensics.

Always do an autopsy, too. Pressurize the bad heat exchanger and cut it open so you can see the failure. You might get some help from the manufacturer.

coztemur
22-04-2007, 07:45 AM
Hi
Before replacing evaporator and compressors you have to know reason of blowing. This is probably dirth in the water system or low water circulation. You have to check
- flow swich
- Water pressure switch
- Defrost setpoint of the controller
- water temp. sensors of evap.
I do not think using little bit larger evaporator will create problem.
Before the start up you have to make sure no water left inside the system.

Coskun





A customer of us has three chillers with brazed plate heatexchangers from an undisclosed company along with a few of ours. From one of the three chillers the evaporator has blown due to frost.

The supplier says they can deliver a new one by the end of July, machine went down last week!

Both compressors contain more water then oil so they also need to be replaced! They cost almost the same as 3/4 of a complete machine and can be delivered within 16 weeks from ordering!

Is this common?:confused:

We desided to use our one evaporator which is slightly larger in size, costs half and was delivered within 2 days.

Howcome a large company in chillers can't deliver an evaporator within the week?:(

Lowrider
22-04-2007, 11:37 AM
Hi
Before replacing evaporator and compressors you have to know reason of blowing. This is probably dirth in the water system or low water circulation. You have to check
- flow swich
- Water pressure switch
- Defrost setpoint of the controller
- water temp. sensors of evap.
I do not think using little bit larger evaporator will create problem.
Before the start up you have to make sure no water left inside the system.

Coskun


Right! I know what needs to be done and the reason of the rupture! But my question is, is it common that large companies who make chillers, amongst other ac equipment, have such long delivery times for key components such as compressors and evaporators!

Andy
22-04-2007, 01:01 PM
Right! I know what needs to be done and the reason of the rupture! But my question is, is it common that large companies who make chillers, amongst other ac equipment, have such long delivery times for key components such as compressors and evaporators!


In a word yes:)

The parts are built for new chillers on a 12 week plus lead time. They hold next to no stock, the customer (us) willnot pay for stock, all is ordered and built to order.

So why blame the manufacturer for a problem we created, wanting cheaper and cheaper goods:D

Kind Regards Andy:)

Lowrider
23-04-2007, 02:17 PM
Why is it then that we can get all the parts for our machines within the week and they can't? Both factories are in France!

NoNickName
23-04-2007, 02:42 PM
Yes, it is common. No company keeps any spare in stock, these times.

Shakey
23-04-2007, 11:29 PM
Even if there are parts in stock it still usually takes a few weeks! You are better off driving over there yourself!

old gas bottle
24-04-2007, 08:15 AM
its not right by any standard that a manufacturer does not keep a full spares back up service for there products,in or out of warrenty,what are you supposed to tell the customer !, after all when its chargable they make a mint percentage wise, more than the supply of the chiller,if its a car,in most cases they get the parts very quickley because they have a obligation to supply you with one while its being fixed, and as for saying its our fault as a customer thats crazy ! theese people can buy components 3-4 times less than us, in my opinion its bad bussiness practice and all to common.

NoNickName
24-04-2007, 08:44 AM
Hey, old bottle of gas, if you want the things fast, buy the spares prior to faults. It is not right that the manufacturer should bear the costs of warehouse just for your peace of mind.
Be careful and forward-looking next time: buy the spare and YOU KEEP IT IN YOUR STOCK!
There is no obligation for anyone to buy anything and keep it in stock until an old bottle of digestive gas shows up.

old gas bottle
24-04-2007, 04:32 PM
ha,ha,well you will say that nick as you are a manufacturer, as for buying the parts in before it breaks down, well let me think!!!!!! i know, i,ll order a evaporator next week because that one will split on tuesday, it just dont work like that or should not,if you buy something the spares should be available pronto legal requirement or not. we look after a very,very big site and one of the major a/c brands will not be selling anymore on there purely because of this very thing.

NoNickName
24-04-2007, 05:00 PM
I can't nurse customers, not enough long-sighted to buy and keep some spare on site. If the a/c plant is mission critical, one cannot rely on manufacturer for next-day spare parts delivery.
Or, get ready at paying the chillers twice as much as average market price. Then, we can think about keeping spares in stock for your peace of mind.

Lowrider
24-04-2007, 08:01 PM
I also work for a manufacturer and we keep almost all electrical components at our storage in Holland, along with oil and other components, such as valves, solenoides adn transdcers. Almost all compressors can be delivered within a week from our factory in France and the ones from china or the us within a month. All fans e.d. take 3 to 4 days! Evaporators or in case of shell and tube just the tubes we usually can have over night! So manufacturers not keeping stock? Only one offs and specials take a bit longer!

I understand manufacturers can't keep everything in stock, but even Danfoss can't deliver new performer scrolls faster!
And if the machine in this case wasn't a common one I would understand, but it's very common in Holland!

I was only wandering if more of you have similar problems with manufacturers or that it is just this one case!

NoNickName
24-04-2007, 08:21 PM
Yeah, ok, contactors and thermal switches are not what I call "mission critical" spares, as most of those components are bought at the hardware store at the street corner. No professional engineer will buy transducers or solenoid coils from original manufacturer.
But e.g. 12 poles fans from Ziehl have got a wonderful 17 weeks delivery times for OEM. Again, it all depends on the width of the offer. We've got 194 different chiller models in our catalogue.

taz24
24-04-2007, 09:17 PM
Hey, old bottle of gas, if you want the things fast, buy the spares prior to faults. It is not right that the manufacturer should bear the costs of warehouse just for your peace of mind.
Be careful and forward-looking next time: buy the spare and YOU KEEP IT IN YOUR STOCK!
There is no obligation for anyone to buy anything and keep it in stock until an old bottle of digestive gas shows up.

Sounds like your a manufacturer eh:)

taz.

NoNickName
24-04-2007, 09:27 PM
Sounds like your a manufacturer eh

Yes, I'm an engineer of a manufacturer

Tycho
24-04-2007, 09:30 PM
ha,ha,well you will say that nick as you are a manufacturer, as for buying the parts in before it breaks down, well let me think!!!!!! i know, i,ll order a evaporator next week because that one will split on tuesday, it just dont work like that or should not,if you buy something the spares should be available pronto legal requirement or not. we look after a very,very big site and one of the major a/c brands will not be selling anymore on there purely because of this very thing.

If the client is that important, why don't you keep spares in stock?

it costs alot to keep spares in stock, if you are not willing to do it, how can you expect the manufacturer to?

(just poking you in the side here ;))

But truth be told, most manufacturers keep a bare minimum in stock, and I think I can say that the company I work for has a bigger stock of spareparts than some manufacturers do :) atleast I know that we have the biggest store of danfoss valves in Norway

TXiceman
24-04-2007, 09:46 PM
I worked for a small chiller manufacturer that stocked some of the more common components that were used. Most of the items were supplied to them with an OEM price basis from the factory. Numerous times I saw where we needed a specific OEM valve such as a Sporlan TXV, we were out of stock, Sporlan was quoting 5 weeks or better for a valve. The customer got his knickers in a wad because he called the local supply house and could get the valve off the shelf. Proble is that the valve was double our OEM cost. The same thing could happen on compressors, vessels and heat exchangers.

Manufacturers now employ a J-I-T (just in time) order/manufacturing technique. They order in supplies to arrive for a specific manufacturing date. Parts setting on the shelf cost money and increase the cost of the product.

Ken

The MG Pony
24-04-2007, 10:01 PM
One should all ways have at least one spare in the truck and one in the store is our saying.

In the computer industry for fail safe drives you have 2 to 200 Hot spares spinning away and in the shelf under it you have another 1-100 cold spares.

if you don't then we'll just luagh at you when your whole network imploads becuase you tried to save a few cents.

Like Nonic said, anticipate what will fail and try and keep at least one of the item on stock at the ready.

TXiceman
25-04-2007, 02:35 AM
By the same token, we have customers that get a bit irritated when they call wanting documents and records on a 15 or 20 year old unit. We probably have them, but they are archived and not in any kind of film or tape. They are off site and have to be retrieved at a cost to us.

Sad part is we gave them several copies of these manuals and documents with the equipment and we kept only one copy. They can not keep up with 10 copies but expect us to have 1 copy at our finger tips. Then they scream about the cost of making them a copy.

Parts are the same story, we keep most of the normal spares (gaskets, filters, relays etc), but we will not keep a $100,000.00 compressor, motor or heat exchangers on hand. With the equipment we give them spares list which list normal availability of each item and break them down into commissioning spares, operating and maintenance spares and long term spares.

Right now I have a customer with a large steel case screw compressor which is heart of the plant. It is down, he is down. Lead time on the bare compressor is 6 months. It will take 4 to 5 days to do a rebuild on it if it is repairable. How many days or hours production does it take to pay for the compressor....no many. Operations wants a spare compressor, bean counters say too much money to leave setting on the shelves for several years.

It is up to the customer to make an assessmsnt of the need for spares and decide if he wants to carry spares or just take his chances.

Ken

US Iceman
25-04-2007, 04:03 AM
It is up to the customer to make an assessment of the need for spares and decide if he wants to carry spares or just take his chances.


That's very true. My experiences in chem plants was that they stocked spare compressors for just this reason. The actual process made so much money the cost of storing compressors was a very small cost to absorb.

Manuals are always interesting. Hardly no one pays any attention to them until they are needed. I recently found the equipment manuals in one equipment room covered in dirt, oily rags, and other junk sitting in a box which looked like a trash bin.

The manager said this was where the manuals were supposed to be as he got upset when we mentioned they should filed away some place safe.

When I worked for a manufacturer we had the same problem. Someone would call in asking for copies of O&M manuals for a custom-built package. We always kept a single record copy and they wanted it for free!

Sometimes people are their own worst enemy.:D

old gas bottle
25-04-2007, 08:12 AM
i agrree with most thats been said,such as compressors can be bought from anywhere or re-maned quickley,controls/transducers/probes ect the same, but at least the manufacturer should do is have a arragement with there supplier to fast ship parts out direct to there customers if they choose not to hold stock,of course when out of warrenty critical machines should have a spares package on site [if the customer will pay]my beef is there should allways be a good warrenty and spares back up from all manufactures as part of the sevice, i just think thats how it should be.

NoNickName
25-04-2007, 08:14 AM
i just think thats how it should be.

But it is not.

Dan
25-04-2007, 11:14 AM
I think another point can be added to this lengthy discussion, and that is the terms OEM and "Aftermarket."

After a large company took over the manufacturer I used to work for, the MBA's quickly moved to what is now called "Aftermarket parts." 1,000% multipliers came into play and an effort to make components unique... e.g.(unavailable at the wholesale stores) also came into play. However no effort was produced to have these parts available on an immediate basis. In fact, the obsoletion of available parts was shortened. It used to be true that there was at least an implied obligation to stock "obsolete" parts for 5 years. I have seen examples where model changes happen so often that a 2 year old part falls into the obsolete category and the 1,000% multiplier range.

Carrier mini split fan relay board on a 2 year old fan coil: $565.00. Just a random example of the usurious tactics employed by manufacurers. 2 week lead time also.

There are many discount automobile chain stores in the U.S. taking advantage of this usury. Regrettably they have to wait for a couple of years before they can provide reasonable alternatives and inventory.