21st floor condo low water pressure issue...need advice

[richard1977]

2 hours ago, WaveHunter said:

 

I realize that heaters with booster pumps seem to not be sold in Thailand, but this unit is not from Thailand; I would be importing it from elsewhere.

 

they are available in thailand.  i have a Joven SL30P.

 

you should be able to get either a Joven SL30P (available on lazada) or a Clarte WHM451P (available from boonthavorn,  lazada, shopee and probably other places.  homepro used to have these too).  the clarte on shopee for ฿3,290 is a pretty cheap price.

 

both of these shower heaters have small built-in pumps.

 

edit: there is also a Clarte WHGP45 on shopee for only ฿1,890

 

(you can see the performance difference that the small added pump makes here - 

 

[WaveHunter]

45 minutes ago, richard1977 said:

 

they are available in thailand.  i have a Joven SL30P.

 

you should be able to get either a Joven SL30P (available on lazada) or a Clarte WHM451P (available from boonthavorn,  lazada, shopee and probably other places.  homepro used to have these too).  the clarte on shopee for ฿3,290 is a pretty cheap price.

 

both of these shower heaters have small built-in pumps.

 

edit: there is also a Clarte WHGP45 on shopee for only ฿1,890

 

(you can see the performance difference that the small added pump makes here - 

 

What's your personal assessment of the Joven SL30P?  How much did it really boost pressure, and did the temperature stay above at least 40 at highest pressure setting?

[richard1977]

12 minutes ago, WaveHunter said:

What's your personal assessment of the Joven SL30P?  How much did it really boost pressure, and did the temperature stay above at least 40 at highest pressure setting?

it does boost pressure, but the difference isn't huge.  maybe less than 50% difference?  the performance would be similar to the Clarte WHGP45 in that youtube video.  i suspect that all of these would be pretty similar internally and perform similarly.  sorry, i'm not in thailand at the moment, otherwise i'd run a test on it.

 

it has no problem heating to 40 with the pump on (the joven only has an on/off switch for the pump, unlike the clartes which have a dial)

[WaveHunter]

2 minutes ago, richard1977 said:

it does boost pressure, but the difference isn't huge.  maybe less than 50% difference?  the performance would be similar to the Clarte WHGP45 in that youtube video.  i suspect that all of these would be pretty similar internally and perform similarly.  sorry, i'm not in thailand at the moment, otherwise i'd run a test on it.

 

it has no problem heating to 40 with the pump on (the joven only has an on/off switch for the pump, unlike the clartes which have a dial)

Yeah, that video you posted wasn't too impressive though I wasn't really sure what those guys were talking about but the waterflow did not impress.  Even so, just a little more pressure than I have would be fine.  I just hate how long it takes to get the shampoo out of my hair LOL!

[sometimewoodworker]

7 hours ago, WaveHunter said:

@sometimewoodworker Thanks for the reply.

 

The input water temperature (unheated) in my condo is 28° C and my present 6kW heater is only raising it to 35° C...so I guess you are saying my present heater is not working well.  It does look pretty old so I guess that's why my hot water temps are so low..

 

However, You are incorrect that the unit I am looking to purchase does not actually contain a pump.  It does indeed contain one (see attached pictures)

 

 

I realize that heaters with booster pumps seem to not be sold in Thailand, but this unit is not from Thailand; I would be importing it from elsewhere.

 

After discussing with manufacturer's rep, she assured me that, based on the chart they provided to me (below) and the fact that my condo's incoming (unheated & unrestricted) water flow is presently 3 liters per minute at 28° C that I should expect at least 40° C+ at the showerhead and a boost of (unrestricted) water flow up to around 5 L/min, and perhaps even more temperature & water flow.  (Note that this chart is for delta change, not absolute comparison.)

 

Fact is, I actually did ask her if perhaps I should hook up their heater / booster pump in series with my present heater, and she advised it would not be necessary.

So, I guess my question is really just whether this sounds reasonable and I'm not being mislead by the manufacturer, and whether there are any dangers to the pipes in the walls from increased pressure (which I'm now suspecting is probably not an issue.

 

As to danger of pipes leaking under increased pressure,  it’s completely impossible to say that you will be OK, while it will probably be no problem there are no guarantees.

 

If your input temperature is at 28C you should be getting over 40C with your unit, I do with mine. So yes it’s faulty.

 

However your flow is too high AFIR you need to check but I think the standard is under 2 litres per minute, so that’s probably part of the problem.

 

 

the 

[Yellowtail]

A cheap, tiny pump will not increase the flow in your shower significantly. 

[sometimewoodworker]

11 hours ago, WaveHunter said:

Even so, just a little more pressure than I have would be fine.  I just hate how long it takes to get the shampoo out of my hair LOL!

It’s the water flow not water pressure that helps wit that,

[sometimewoodworker]

20 hours ago, WaveHunter said:

realize that heaters with booster pumps seem to not be sold in Thailand, but this unit is not from Thailand; I would be importing it from elsewhere.

It would be helpful if you gave the details (model number, maker) of the unit you are thinking of, there are probably more details available.
 

As you are going to do something, taking the existing unit down turning it upside down and filling it with white vinegar for a couple of hours then running the water in reverse, you may need to do that a couple of times, should clear it out. It would also tell you if it’s restricted.

[WaveHunter]

7 hours ago, sometimewoodworker said:

It’s the water flow not water pressure that helps wit that,

Well, the water flow is going to be dependant on water pressure, wouldn't you agree?

[WaveHunter]

14 hours ago, sometimewoodworker said:

As to danger of pipes leaking under increased pressure,  it’s completely impossible to say that you will be OK, while it will probably be no problem there are no guarantees.

 

If your input temperature is at 28C you should be getting over 40C with your unit, I do with mine. So yes it’s faulty.

 

However your flow is too high AFIR you need to check but I think the standard is under 2 litres per minute, so that’s probably part of the problem.

 

 

the 

I'm confused what  you are saying about water flow "is too high AFIR" ??  I checked the flow by taking the shower head off and running water water intp a 1 liter bucket; it took about 20 seconds to fill the bucket...thus 3 L/min.  I googled and found several references that most good hotels have a water flow of 6-7 L/minute.  So that's what my assumptions are...that my water flow is about half what would be desirable.

[sometimewoodworker]

1 hour ago, WaveHunter said:

Well, the water flow is going to be dependant on water pressure, wouldn't you agree?

No, they are completely different. You can get high flow low pressure (Amazon river), and (think of an extreme case of water cutting) very low flow with extremely high pressure 

[sometimewoodworker]

1 hour ago, WaveHunter said:

I'm confused what  you are saying about water flow "is too high AFIR" ??  I checked the flow by taking the shower head off and running water water intp a 1 liter bucket; it took about 20 seconds to fill the bucket...thus 3 L/min.  I googled and found several references that most good hotels have a water flow of 6-7 L/minute.  So that's what my assumptions are...that my water flow is about half what would be desirable.

Bahh humbug, you made me go to my Häfele catalog, and it’s really heavy, ???? taps are limited to 5Lpm rain showers 9Lpm and bath mixer taps to 22Lpm.

 

We probably have about 23C water, I can’t find a thermometer ATM , our 6,000W units can get 37C at full flow but are struggling with 40+, with lower flow the can get to 42C.

[WaveHunter]

1 hour ago, sometimewoodworker said:

Bahh humbug, you made me go to my Häfele catalog, and it’s really heavy, ???? taps are limited to 5Lpm rain showers 9Lpm and bath mixer taps to 22Lpm.

 

We probably have about 23C water, I can’t find a thermometer ATM , our 6,000W units can get 37C at full flow but are struggling with 40+, with lower flow the can get to 42C.

Bah Humbug???  Sorry, but what's your point.  I'm not quite sure.

[WaveHunter]

2 hours ago, sometimewoodworker said:

No, they are completely different. You can get high flow low pressure (Amazon river), and (think of an extreme case of water cutting) very low flow with extremely high pressure 

I think we've been through this before somewhere.  Your "river" example is flawed.  Water is not compressible, so when a river narrows, the only reason that flow increases is because the water can rise in height.  If it could not rise, the velocity of flow could not increase.

 

Obviously water pressure and water flow are directly related.  If that were not the case, living on the top floor of a hi-rise condo would not result in poor water flow I am experiencing.  

 

If you want a more scientific explanation, there is Bernoulli's Law.  It explains the relationship between pressure, velocity, and elevation in a moving fluid (liquid or gas).  It explains why the shape of an airplane wing allows it to defy gravity,  why rivers seem to flow faster in narrows, and even why my top floor condo has weak water flow ????

 

[sometimewoodworker]

1 hour ago, WaveHunter said:

Obviously water pressure and water flow are directly related. 

It seems that you missed physics 101 as that is not nearly complete.
 

At the extreme you need some pressure to have any flow, however if your pipes are too small you won’t get much flow.
 

With the same pressure increasing the pipe diameter will increase the flow.

 

We knew that power cuts here are common so have a minimum of 0.3 psi. Because we wanted to allow showers with that pressure in mind we have used 32mm pipe rather than the common 12mm. So we can have at least walking water when the power is out. With the 12mm we would only have a dribble certainly not enough for a shower. A larger supply pipe would have given a higher flow but that’s enough for us.

 

1 hour ago, WaveHunter said:

think we've been through this before somewhere.  Your "river" example is flawed.  Water is not compressible, so when a river narrows, the only reason that flow increases is because the water can rise in height.  If it could not rise, the velocity of flow could not increase.

You are introducing a new point that was never in my post, arguing against that point so “supposedly” winning, my point is the flow in a non-constricted section of the river is huge the pressure is small. The exact opposite of a water cutter where the pressure is huge but the flow is small. 
 

physics is fun for some and incredibly difficult for others.

[sometimewoodworker]

1 hour ago, WaveHunter said:

Bah Humbug???  Sorry, but what's your point.  I'm not quite sure.

Irony ???? or humour, life’s too short not to inject some of that into it. 
 

Anyway I will bow out and leave you to do things your way 

 

TTFN

[WaveHunter]

1 hour ago, sometimewoodworker said:

Irony ???? or humour, life’s too short not to inject some of that into it. 
 

Anyway I will bow out and leave you to do things your way 

 

TTFN

No offense intended; I just have no idea what you were saying.

[Yellowtail]

9 hours ago, WaveHunter said:

No offense intended; I just have no idea what you were saying.

 

A better analogy might be standing in a heavy rain storm, or having a bucket of water  poured over your head. Little pressure, yet plenty of volume. 

 

If you are able to disconnect the hose feeding the water heater, see how fast you can fill the bucket with the that hose. If it is significantly faster than with the shower hose, the heater is restricted and you need to either clean it out or replace it. 

[lopburi3]

36 minutes ago, Yellowtail said:

If you are able to disconnect the hose feeding the water heater, see how fast you can fill the bucket with the that hose. If it is significantly faster than with the shower hose, the heater is restricted and you need to either clean it out or replace it. 

Suspect it will always be significantly faster - the heater restricts water flow by design with much smaller pipes than water hose (even when they are clean).

[bankruatsteve]

FYI: The velocity of flow is a factor of pressure, either gravity or a pump.  IE: no pressure, no flow.  The flow volume is a factor of the cross sectional area of the conduit and the velocity.  

[Yellowtail]

8 hours ago, lopburi3 said:

Suspect it will always be significantly faster - the heater restricts water flow by design with much smaller pipes than water hose (even when they are clean).

 

I guess it would depend on how you define significant. While I know nothing of water heaters, doubt very much smaller tubing is used "by design" to restrict flow, I imagine it is used to increase the contact area per unit volume of water. 

 

I know when I disconnect the feed hose from my shower heater it does not seem to put out any more than is I just pull the head off the shower hose, although I have not times it. 

[WaveHunter]

On 12/19/2020 at 7:28 AM, Yellowtail said:

 

A better analogy might be standing in a heavy rain storm, or having a bucket of water  poured over your head. Little pressure, yet plenty of volume. 

 

If you are able to disconnect the hose feeding the water heater, see how fast you can fill the bucket with the that hose. If it is significantly faster than with the shower hose, the heater is restricted and you need to either clean it out or replace it. 

The best analogy I can think of is having a garden hose with no nozzle on it.  You have have a high water flow, but no pressure.  If you put your thumb over the end of the hose with high water flow, you get the high pressure delivery that is desired.  Without sufficient water flow however, all you really get is a higher velocity mist

 

My point...BOTH water flow and water pressure matter

[WaveHunter]

On 12/19/2020 at 8:31 AM, bankruatsteve said:

FYI: The velocity of flow is a factor of pressure, either gravity or a pump.  IE: no pressure, no flow.  The flow volume is a factor of the cross sectional area of the conduit and the velocity.  

Sounds right to me ????

 

[Yellowtail]

1 hour ago, WaveHunter said:

The best analogy I can think of is having a garden hose with no nozzle on it.  You have have a high water flow, but no pressure.  If you put your thumb over the end of the hose with high water flow, you get the high pressure delivery that is desired.  Without sufficient water flow however, all you really get is a higher velocity mist

 

My point...BOTH water flow and water pressure matter

 

And they never matter more than when buying a pump.

 

Did you check your flow before and after the heater? 

[WaveHunter]

1 hour ago, Yellowtail said:

 

And they never matter more than when buying a pump.

 

Did you check your flow before and after the heater? 

Actually I only checked the flow at the shower head pipe (with shower head removed).  It was 3 liters per minute.  I see what you're getting at...if flow from inlet to water heater is the same, the booster pump may not work.  Good point.  Then again, maybe the pump will "suck" more water from outside???

 

At any rate,  even if the new heater with booster pump doesn't improve flow, it will still fix low temps so I'll probably buy it anyway since my present heater (6kW) is only putting out 35-37 degrees C max.

 

I did buy a new "high velocity" shower head and that has improved the flow a little bit.

[Yellowtail]

17 hours ago, WaveHunter said:

Actually I only checked the flow at the shower head pipe (with shower head removed).  It was 3 liters per minute.  I see what you're getting at...if flow from inlet to water heater is the same, the booster pump may not work.  Good point.  Then again, maybe the pump will "suck" more water from outside???

 

At any rate,  even if the new heater with booster pump doesn't improve flow, it will still fix low temps so I'll probably buy it anyway since my present heater (6kW) is only putting out 35-37 degrees C max.

 

I did buy a new "high velocity" shower head and that has improved the flow a little bit.

 

If you get the similar flow before and after the heater, the heater is not full of scale. If the flows is much better before the heater, the heater is the likely the problem. 

[aeae]

On 11/28/2020 at 11:37 AM, Kwasaki said:

Try the pump as suggested if there's still not enough water getting to the pump buy a small water storage tank that get filled with the condo incoming water a day pump water from tank, your get your power shower then. 

 

Any link to such tank please ? thanks.

 

[lopburi3]

6 hours ago, aeae said:

 

Any link to such tank please ? thanks.

 

Most people would not have room for such a storage tank in a condo and suspect many would not allow because of weight anyhow but any building supply sells water storage tanks.  A good shower head might be a viable option if unable to increase pressure.  I have bought below type (although have high pressure - they provide good coverage but are still soft feeling).  Have both SS and Al types and they both work well (AL is much lighter in case of drop on toes)

https://shopee.co.th/ฝักบัวแรงดันสูง-ฝักบัวอาบน้ำ-ฝักบัว-น้ำแรงและนุ่ม-สปา-สแตนเลส-304-หัวฝักบัว-ฝักบัวอาบน้ำแรงดันสูง-shower-head-i.160139238.8678236328

[Kwasaki]

6 hours ago, aeae said:

 

Any link to such tank please ? thanks.

 

In a Global house they have bins with lid and dustbins You can use as a small storage tank to put where ever possible near the shower room.

Fit water inlet pipe running from the existing water pipe feed and stop-cock then run a pipe to the  pump that has separate breaker and it must be EARTHED and from pump to pipe that feeds the shower head.

There's many others places about but I find Global house has just about everything you need. 

You have be a competent handyman to carry it out. 

[aeae]

I would prefer a proper tank rater than a bin please....