Re: Low water pressure

You might want to check first the size of the down pipes they installed.

My overhead tank is on a 5th floor rooftop... the water flow is OK but I would have wanted it to be stronger specially on the 4th and 3rd floors. I was not around during construction and was informed later that the main pipes were not sized according to the flow I was looking for.

Re: Low water pressure

I agree with JayL, your piping may not be adequately sized. If the water supply to the ground floor have a separate isolation valve you may try to reduce the opening to control the flow so that your piping at the the 2nd floor will not get starved. If it doesnt solve the problem you may have to install a small booster pump for the 2nd floor. Using a larger diameter pipe will give you more volume but the pressure will not improve that much unless you raise the elevation of your tank. In my opinion the easiest solution is to install booster pump with pressure tank, but then it will have an effect on your electric bill. You can do a cost comparison on what will be the best solution to undertake.
Btw elevated water tanks must have a vent to the atmosphere to keep the pressure head constant, so the cover should not be air tight if there is no separate vent pipe installed. HTH

Re: Low water pressure

Thanks for the replies.

Pipes are about 1 inch in diameter.

If I remember correctly, there are about 4 or 5 pipes coming out of the reservoir. Would there be an issue if I install the booster pump on the third floor then divert the pipe into two outlets? Two of which will supply water on the 2nd floor where water pressure is a bit low.

Re: Low water pressure

I dont see any major issues installing it in the 3rd floor and splitting the discharge of the booster pump into two equal diameter pipes. There will be some pressure loss on the elbows but it will not be significant.

Re: Low water pressure

The faucet in our garage ( used for car washing ) has a booster pump equipped with a switching device. It only turns on the pump when there is water flow out of the faucet. Automatically turns off the pump when faucet flow stops.

It's the small pump .... hose either goes to the pressure washer or just stand alone use ( boosted water pressure )

Do you think a setup like this will work for your application?

Re: Low water pressure

^The automatic switch is just what I need. What's the smallest pump available? Maybe 1/2 HP if there is one. Around how much does one cost?

Re: Low water pressure

I strongly suggest you show it to qualified people to look at your needs or post as much pictures to get the correct recommendation. You can add an overhead tank or a booster pump only to find out that it wouldn't work. You end up wasting more money instead of saving. It often doesn't mean when you spend less you end up saving, often when you skimp on materials or expertise you end spending more.
Posted via PHM Mobile

Re: Low water pressure

Your overhead tank is on the third floor. Is your 3dr floor a roofdeck where the tank is elevated on a platform? If so, how high is the platform?

I'm asking because the shower pressure on your 2nd floor is determined by how high the elevation difference is between the bottom of your tank to your shower head (minus any constrictions in your pipes).

If your pipes are ok:

Since water pressure is ok on your ground floor, you will need to elevate your tank to a height equivalent to the difference in elevation between your ground floor shower and the current bottom of the tank.; probably raising at least 3 meters more. Not sure if that's an option for you.

If it is, then next problem is that your ground floor pipes may get too high a pressure. I wouldn't bet on it but it's a risk.

A pump with a small pressure tank dedicated to the 2nd floor may be the best solution. Half HP would do with a small stainless pressure tank and a pressure switch.

But, as some people here suggested before, check your pipes. It's circa 80s so it would either be GI or PVC (probably not the new HDPEs). If GI, you may have some tuberculation in which case you are losing head. If pipe replacement is an option, try using HDPE. They're more flexible so less need for bends, lasts a long time, and has better jointing (socket fusion or compression fittings).

If your pipes are PVC and you install a pump, raise the pressure gently and observe for leaks. PVC joints are usually done with solvents and, though that should be ok, alot of pipefitters I've seen do not practice proper methodology (e.g. cleaning the butts, allowing sufficient curing).

Re: Low water pressure

@balarila,

Yes its on an elevated platform. about 12feet from the roof deck. The reservoir is a bit old. Might be a good time to replace it and elevate the tank as well. The house was repiped about five years ago using conventional GI.

I assume there wouldn't be any problem with the water pressure at the ground floor since only the two pipes from for the 2nd floor will be pressurized.

Thanks for the replies. I will update this thread from time time.

Re: Low water pressure

If your tank is already on a 12foot platform, I doubt if elevating it further to achieve the pressure you want would be feasible nor safe. Adding a height equivalent to one floor of your house would mean the platform would be more than 20feet tall. You will need to consult the building restrictions in your area. Remember also that 1 cubic meter of water weighs a ton. You will have a tall, top heavy structure on your roofdeck.

I think a pump, pressure tank, and pressure switch is still your best bet.

To those of you who plan to use elevated tanks to improve pressure, note that one meter elevation produces roughly 1.45psi of pressure. You would want no less than 15psi on your shower supply. Lots of people like more than 40psi. Pipes, if installed properly, should be able to take 100psi. But be sure to check the limit of your water heater. My old Champ heaters had a limit of 90psi.

Hope this helps.

Re: Low water pressure

@bala
does your 100psi apply to ordinary pvc pipe? i've been looking at the newfangled pex pipes but the added expense and the need for heat welding keeps me away.

@jason
bala's right. the pressure tank will only be for bathroom use anyway, so you won't need a big one anyway.
it's likely that elevating the tank will not save electricity. if. the tank's high enough to give enough pressure to your showers, likely it will be too high for nawasa pressure to feed. so you'll end up pumping the wa ter anyway. and instead of just pumping the water for the second floor, you'll be pumping all of the water you use.
Posted via PHM Mobile

Re: Low water pressure

Yes, Zepol. PVC pipes (the regular schedule, can't recall what) should easily withstand 100psi. We hydro test PVC at 150psi (I work at Manila Water). Usual problem, though, are the joints due to careless contractors.

On PEX (cross linked high density polyethylene), sorry, can't help you much. We use regular HDPE for street piping. From what I know in home or building applications, socket fusion (a form of heat welding) is available for HDPE jointing and appurtenances. When done properly, fused joints are stronger than the pipe itself.

BTW, there's no NAWASA anymore. MWSS (the NAWASA successor) contracted out water treatment and distribution operation. We (Manila Water) serve the eastern part of MetroManila and Rizal while Maynilad serves the west plus southern Cavite.
Posted via PHM Mobile

Re: Low water pressure

I might replace the water reservoir for sanitary purposes. As it doesn't get proper sealing. Debris and whatnots can easily get into the cover.

Will look for a pump this week.

Thanks for the tips and advices. Been learning a lot here. Thanks!

Re: Low water pressure

@bala

BTW, there's no NAWASA anymore. MWSS (the NAWASA successor) contracted out water treatment and distribution operation

hehe, old habits die hard - NAWASA's one of those names like Dewey Boulevard and Governor Forbes Street. 🙂