luudee

17 minutes ago, Artisi said:

Remove the NRV from the discharge side, not required, however you need a NRV on the inlet side to maintain  the system pressure, purchase one from Grundfos to suit the pump model. 

In operation the " pressure system"  encompasses everything from the pump side of  the inlet NRV, pump, pressure tank, and pipework -  the reason as to why you don't need a discharge NRV as the whole system in maintained under pressure by the pressure tank. 

 

There should also be an electrical pressure switch to control and maintain the system pressure, to sense a drop in system pressure and run the pump until the pressure is back to the set pressure. This should be fitted somewhere between the pump discharge and the pressure tank. 

The word professional shouldn't be used at all - rank amateur probably doesn't even suit. 

 

Let me know if I can assist further. 

 

Of course, there is a pressure switch ... 

I don't quite understand what you are saying in the first paragraph. This is a well working system, 

except that I can not find a check valve that can handle the backpressure and falls apart ...

The Check Vale you are showing in your second post has a plastic "lid" that closes it. This type of

Check Valves will not hold for a day ... 

I understand now that placing the Check Valve in front of the pump is the prefered choice.

In my case, the inlet of the pump is connected to two 2,000 L water tanks.  The pump is at the

ground level with the tanks, so there is enough pressure from the tanks to prime the pump if needed ...

Are there any other reasons to change the location of the Check Valve ? 

Will that solve the problem of destruction of the check valve ?

Thanks,

rudi

43 minutes ago, Pib said:

I would just remove that check valve on the discharge side...."normally" they are not needed except with certain setups.  

 

But you should have one on the input/suction side to ensure no backflow to the water source, loss of pump prime, etc.

 

And when they have failed in the past, how did you know they had failed since you can't see into them unless removed and inspected.  What kind of water flow/pump problem occurred to indicate the check valve had failed?

 

Well, when they fail, the pump constantly runs as it can not build up pressure.

It's a constant pressure system. The pressure tank usually holds enough water that the pump only turns on when the system pressure has fallen below a set point.

rudi

3 minutes ago, Artisi said:

Are you using or have you tried the NRV that is normally supplied on the inlet side of the Grundfos CH? 

I assume NRV stand for "non-return valve", which is basically a check valve, correct?

The system was built by a "professional" (used very carefully here, lol) ...

I have no idea why the check valve was installed after the pump, or why it would make a difference in the first place ...

As I said, the system actually works quite well, except that it eats check valves ... 

rudi

5 minutes ago, Pib said:

Strange...I use a Mitsubishi pump that generates 2.8 bars with my 9 year old check valves. Your 3.5 bars pump really ain't that much more than a 2.8 bars pump.  

 

You may have some backflow/pump impeller kickback through the pump when it cuts off due to pump design or just your piping setup.   To stop/minimize that you may need a check valve on the "discharge/output" side.  Do you also have a check valve on the "discharge/output" side or only on the suction/input side?  

 

It's actually a constant pressure system there is a large pressure tank (150L) attached as well (at the pump output).

I only have a check valve at the output of the pump.

rudi

5 minutes ago, Pib said:

 

 

Is this just a residential water pump operating at a few bars or some high pressure/specialized pump?  

 

If just a typical residential pump heck I have around a half dozen standard issued brass check values in my lines....all valves around 9 years old....none have failed and a few I've had a chance to inspect about a year ago when doing some rearrangement of my pressure pump and storage tank....all looked in good condition internally and were still working fine.   

 

And when you say check valve I'm assuming you mean one-way flow values verses something else?

 

Sorry, it's a Grundfos, I get these two always confused, specifically, it's a Grundfos CH8-50 pump.
My application is residential, perhaps a bit larger setup than typical.

Regardless, the fact that the Check Valves last in your case for 9 years, doesn't help me.

The line pressure is about 3.5 bar. When the pump stops and the valve closes, it generates

a very loud bang. There is a lot of force behind it ...

I did not design this setup, it was done by somebody who claimed to know what he was doing.

In any case, I am happy with my setup and had it for a very long time, I just want to find

a check valve that will last longer ...

Thanks,

rudi

I have used the ANA variety, they lasted for about 3 weeks. On one the flap hinge

failed, on another the rubber seal came off and kept the valve open. I don't think

I have seen the SANWA before. KITZ lasted the longest so far with over 4 months

in service ...

I was hoping to find local options before going to eBay and such.

I wonder if there is a stainless steel variety available locally ...

Thanks,

rudi

Hello,

I am looking for a check valve, 2", swing type.

Now, I have seen what's available at the local shops, mostly china made brass variations. 

Those tend to last for a couple of weeks before they break in various ways.

I am looking for a better quality variation, preferably stainless steel, swing type. 

Any suggestions where a semi-professional variation of a check valve can be obtained in

Thailand ?

Again, I have seen and tried almost every brass version, but my 1.5 hp Danfoss pump trashes them all ...

Many Thanks,

rudi

My experience has been that even if you find that exact tile from that exact manufacturer

unless you find exactly the same batch, the colors will be off slightly.

The batch number is usually printed on the boxes. When I buy tiles, I always check that they

come from the same batch, and buy a few boxes extra - just in case ...

rudi

I would not throw them away, but rather try to get proper service.

I build my own constant pressure system, with a quality pump, and pressure tank, etc.

I have a larger than average house/big family ...  Had it now for over 10 years, only minor

repairs/maintenance ...

I have a problem with rats, they tend to chew up the AC outside compressors/electronics.

We have managed to keep it all sealed for several years now. 

Lately, I've been having problems with one AC unit, which is leaking coolant.

The first "repair" rice-farmer, just topped it off and told me to call him when it stops working again.

again. The second one was a bit better, tried actually to find the part that was leaking and re-weld it ...

But he failed as well ... they never do proper pressure tests ... not fun and takes to much time.

Now, based on a recommendation of a friend, I contacted daiken directly, and am waiting for them

to send some "qualified" monkey to actually fix it ....

Overall my Daiken Inverters have been in service for 6-8 years ... I have also a large (cassette) Mitu

unit in my bedroom and also very happy with (10 years going strong). Had to replace the compressor

starting Capacitor quite early after purchase, but nothing else ...

luudee

I use real security cameras from IQeye, 750 serries. They run about $1200 USD Each.

Record directly to my NAS which is running "Surveillance Station" ...

Yes, may be overkill for what the OP wants, but you get what you pay for ...

Also remember to get a UPS for all cams and recorder ....

rudi

On 4/19/2017 at 7:41 PM, Arjen said:

Scotch Brite will make polished SS dull.

 

 

Thank you so much for this info !  :)

I will not try this than

rudi

4 hours ago, VocalNeal said:

Could have simply been vinegar. Worth a try as it is cheap at Tesco.

 

Do you use the Wenol with Scotch-Brite or simply with a rag. 

 

Living near the coast (Pattaya, Hua hin) makes it worse. 

 

 

In a previous life? I tried that cleaner on stainless urinals in a bar. It didn't do squat. I think elbow grease is the only real choice?

 

Just a rug, haven't tried with Scotch-Brite. Will try that ...

rudi

Maybe it is worth getting this:

https://www.aliexpress.com/item/2-pin-German-plug-Power-Consumption-Meter-Energy-Electricity-Usage-Watt-Calculator-Monitor-free-shipping/32795867193.html

(make sure you get a 220V unit)

rudi

2 hours ago, VocalNeal said:

We have lots of customers with stainless gates.

 

If you can't find AutoSol ? Wenol will work.

 

 

Available at HomePro, Tesco-Lotus etc.

 

Not as good in my opinion but... AutoSol is getting harder to find.

 

Thank you Neal, we have tried Wenol, and are not very happy with it either. Brasso is a bit better, but still not "agessive" enough ...

When the Thai guys initially installed it, they had a spray bottle with some clear liquid, that would remove any dirt and make the steal shine.

That particular shop has disappeared since then, and other stainless shops I have visited refer me to Wenol or Brasso.

Back then I didn't think about asking them. I just remember that they DID not use gloves or facial covers.

rudi

All you guys with the stainless steel gates, how do you maintenance the stainless part ?

Do you guys repolish it, or do any other type of cleaning?

What do you use ?

My worker polishes mine with Brasso, but they just don't get that "new" look anymore ....

(they are about 15 years old now)

rudi

I have one rule in these type of a situation: Imagine you are dealing with a spoiled 5 year old. 

Respond accordingly ...

rudi

Duck is nasty. It has enough acid to etch the top layer of granite. Happened to me as well. 

Depending on how long she let it sit, it can be just the polished layer or deeper.

You might be able to repolish the grant and get the stains out, but the polishing task is no that easy.

Not sure anybody in Thailand can actually do it ....

rudi

I did as other have suggested here, researched wich unit I want online, and

then ordered in from Lazada. Came in 3 days ...

luudee

If you take care of the s/s, the cheaper one will be fine ...

Clean it with some wd40 once a week, and it will last ...

rudi

In my experience, there are several reasons for this type of failure: 1) Blader tank is leaking (air

or nitrogen). This means that the membrane might have failed, in wich case refilling it will only

provide a temporary fix; 2) If your water is hard, you might have limestone build up in the pressure

switch intake.

I don't think #1 can be fixed except by replacing the bladder tank. The second problem might be

fixable by removing the pressure switch and cleaning the intake with a limestone remover, or by

replacing the pressure switch.

Good Luck !

rudi

2 hours ago, David B in Thailand said:

VRH is a high quality brand that has served me well for over ten years in three different homes in Buriram. VRH has some hose items that are stainless 304 with PEX lining. VRH also makes limited stainless 316 fittings, in addition to stainless 304 fittings. I have several VRH taps, shower fixtures and several toilet spray bum guns that work perfect. I have cleaner water than the OP, but VRH show no signs of rust. American Standard is owned by Lixil and may not be the same grade you recall from years ago. 

 

Thanks for sharing your experience David B !  The hose I showed in the picture above is a 304 Stainless Steel, according

to the marking on the package. What is not clear is which part is 304 Stainless Steel. Many other brands will say stainless

steel, but the inside parts are brass. I assume they refer to the mesh outside?  I will pay more attention the brands I buy. In

the past, I valued Haefele very much, as their fittings and such are usually really good quality. But their hoses (with 10y

warranty) had the inside part made from brass. I'm not an expert in these matters, I will keep on trying! Time will tell, lol

Again thank you for your message!

rudi

6 minutes ago, KittenKong said:

 

Mine are over 10 years old. Never had any problems with them. I think your water must be different.

 

Yes, indeed. I have my own well, and the water is very iron and calcium (limestone) rich.

rudi

So I went to every major Hardware Store on Sukhumvit, from Thai Watsadu to

Boonthavorn, and found the below version at Boonthavorn.   189 baht for 20"

long. It says stainless steel, but if you look closely into the opening, I can see

something yellow/gold color.  Will be interesting to see if these will last longer !

rudi

4 hours ago, carlyai said:

From your picture, it looks to me like you have iron in the water. Just going by the inside of the pipe.

If I'm wrong, don't read the rest.

I tapped into an aquifer about 18 m deep, and the water looked beautiful, but all the hoses and fittings, and dare I say it 'leaks', looked like rust.

After a bit of investigation, seems the iron in the water precipitates on contact with air.....hence rust. (The short version).

I put in a tank, for the rust to settle and some backwashable filters, now I don't have that telltail rust signature any more.

Sent from my SM-J700F using Tapatalk

 

Yes, I know I have a high iron content in my water. Even stainless steel will start to rust

after some time.

But these things I am using are made from brass. As far as I know brass does not rust (or oxidize

in any other way).

I too pump my water into a  holding tank first (going through a sand filter), and then have a constant

pressure pump to my house from the tanks.

Thanks,

rudi

55 minutes ago, leyali said:

If it get warm, the PVC thread should not shrink, opposite.
Put a bit more white tape and screw it fully in, more as on the pic.
Yes, there different quality of the glue, I'm very happy with the Thai-Pipe brand. I'm not cleaning with pipe cleaner, but I always sanding the pipe with sanding papers, so the glue can stick better.

4

We have tried various amount of the Teflon tape, trying to put as little on as possible, but

still maintaining the seal.

It is screwed in pretty much to the end. This actually brings up a good point. The PVC fitting

has a bit of "dead area" before the thread begins. I am considering to cut that off ...

rudi