I think so too...but, in the third pic also have the non-return valve. The problem is I don't understand why outlet no. 3 going back to the main pipe into the tank..any idea?

Yup, the non-return valve? yes black pipe is the inlet (from SYABAS PIPE METER outside into tank).. You asked how can inlet and outlet be connected, this one I cannot help you haha..

This is not a new connection. More than 6-7 years already since the last contractor went up to the roof, so I can confirmed that the piping was OK, no problem. Only happened on Tuesday, right after SYABAS maintenance.. I suspect the high water pressure from the main intake (Syabas) caused the non-return valve to go kaput..

But the layout of piping makes me .

I don't know why, especially for the outlet no. 3, is going back to the mainpipe into the tank. This one really . LOL.


Call me idiot, but I don't know about bypass... care to explain a bit?? haha...

Yea I have reduced the water pressure, closed the tap by half.. See if it makes any difference. But long term, gotta change the return valve... When you say expensive, how expensive?


Hey lucifah, thx man for the tip..

What's the diff between swing and spring? what's the difference in cost pulak??

By the way, in your previous posts, you said , why you said clever? Can explain abit? hehe sorry bro..i'm intrigued to know...

this setup usually means you are bypassing the water tank

the water in the tank only flows out if there is no water supply from SYABAS

so if there is water supply, you get the stronger water pressure from SYABAS pumps rather than gravity feed from your roof top water tank

this one is more complicated as you need a motorized valve to stop the water supply once the water level reaches certain level

once i kena like this. simple issue is tank cover bend inward pushing down the pelampung when its close so the inlet wont stop. i just bend down the pelampung arm inward.

ahhh I see...i understand now...thanx!!


Ya at first I thought the same too...I closed the cover, and placed my ear directly on the side of the tank.. I hear no water dripping..so this one can rule out already..

Anyway, I have to wait until weekend only can do DIY..no time la working..

Will try to update how it goes!

clean inside the float valve.. maybe got debris inside

Pelampung not big enough. & try clean the stop valve. After a long period of time, they stainted and difficult to push in.

As what lucifer mentioned, the issue lies with your one-way valve. Instead of visualizing the water flowing out of the tank and into the main pipe, you should visualize it backwards, say main pipe water flowing into the tank outlet pipes (stopped by the one-way valve).

Its a piping system that says in case no pressure from mains, tank water pressure will take over. If got main pressure, it will top up your tank and bypass the tank water usage for outlet 1 and 3. Since one of the one-way valve is faulty, then system fails and it will flow main water into the tank non-stop.

One of the two valves is faulty but my best advice is to replace both to save time from testing which valve is faulty. Just go to any hardware shop and ask for one-way valve with the correct size (measure your pipe diameter). Also, my advice on replacing both the valves is to sumbat outlet 1 and 3 from inside the tank (with a thick cloth and must be tight) and off main pipe tap. Drain the water in outlet 1 and 3 (Just open any tap to outlet 1 and 3). Do valve replacement with two pipe wrench. Don't forget to apply fresh Plumbing tape (white tape).

Too bad my house tanki piping system isn't like that and whenever water shortage, all the taps connected directly to the mains will run dry.

maybe u can try tie some light rope or benang to tank outlet for outlet 1 and 3 inside the tank for simple visual inspection of water back flow due to failing valve..if any failed then better replace them both

Its a good way to test but considering risking more overflowing water from the tank, might as well get it done before your water bill sky rockets.

saja je lah..u think level sensor cheap meh..

u can use float switch for slightly cheaper option. rm 100 nia mah flaotswitch

advance tech maa..

My problem was a bit different from yours.

Last time, my reservoir tank got leak, causing the water to FOREVER enter the tank and for 3 months, my water bill skyrocketed like crazy. Actually a very tiny crack at the bottom near the edge. Solution: put the silicon sealant (water proof) at it and problem solved.

But then again, it happened again. This time i suspected my water pump which i put near the main had caused the water pressure to hammer the tank and perhaps the check valve couldn't stand it. Some more, my water pump was faulty and in the end, i removed the water pump permanently.

Problem solved till today.

So yeah, i guess the water pressure being too strong is highly likely the main cuplrit.

You can go and saman SYABAS nao.

hi tauke. i think my house water tanks need servicing. u do house calls right?

my charges are exorbitantly high

i charge by the hour

no gst though

But if there is no water from SYABAS, the water would flow back to SYABAS main line?
of course i think SYABAS water meter is single way as well.

BTW the sketch of water flow i wrong i guess.
one way valve for master bedroom is wrongly indicated.

LOL. if it flows back to SYABAS main line, then the mter will run backwards, and SYABAS may end up owing you money

Its obvious the float ball has punctured and there is water inside.