Good Water Pressure In House But Not Thru Shower

[MisterMan]

Hi I just moved and the water pressure in my sink and plain tap is great but my shower is a very low.

I have removed a secondary on-off from knob the hot water box, removed a screen filter but still it has not helped. It goes into the box at good pressure but comes out low. The hose from the source to the box is quite short.

SO do I need a new box or can I do this by adjusting the hose? There is a plane faucet right acroos from the shower and the pressure is very strong...

Suggestions for a new box appreciated, specific model and brand etc.

Thanks.

Edited December 16, 2010 by MisterMan

[Pib]

Make sure the shower head is not the problem. Try unscrewing the shower head from its hose and then turn on the shower. If you got good flow from the end of the hose then it's probably a clogged flow restricter in the shower head handle (usually where you screw on the hose...the restricter can usually be removed/pryed out fairly easy) or a clogged shower head.

If that is not the problem trying unscrewing the hose going "into the heater" and see what kind of flow you have from the end of this hose (I think you may have tried this already). Good flow going in but low flow coming out of the shower head hose (shower head removed), then the shower heater must be clogged/restricted.

But if you got low flow coming from the hose going into the heater (which I think you tried), then you need to do some more back tracking of the shower pipes.

Edited December 16, 2010 by Pib

[MisterMan]

Good flow in .. bad flow out.

Looked up in both the entrance and exit with a flash light..

Somewhere in there the flow slows down dramatically.

[little_muppet]

maybe u need to have a water tank with pump now?

[Artisi]

Check inside the heater itself, some of them have a flow control valve fitted, if there is one on your heater maybe it's set at low flow.

[longball53098]

I think many of these instant water heaters have built in flow control to allow the water to be heated properly and that flow control is designed in to the unit. Make all the usual checks of the flow and double check the heater and valves but I think the unit is slowing the water down and nothing but changing it to a brand that allows more water flow will solve the problem.

[Carib]

You just moved, so I assume you don't know how long theirs unit has been in use already. It could be choked up with calcium now.

Remedy; take unit of the wall, hold upside down, fill with vinegar, let it sit for a while, drain in a bucket through a (coffee) filter, repeat procedure. If clogged up, it will show by the amount of calcium.

[Pib]

Since the OP said he removed the inlet screen/filter and it didn't help, and since the manual/spec sheet does not indicate any valves inside the unit other than a minimum water flow sensor to ensure at least 1.5L/min is flowing through the unit before it powers on, then it sure appears to be clogged up internally. Trying Carib's approach above wouldn't hurt.

Maybe even try hooking up the water "inlet hose" to the unit's "water outlet" connector and running water through the unit in the reverse direction might break something loose/help unclog it....if trying this I would recommend you set the heater to not come on/heat up and/or turn off the circuit breaker.

[MisterMan]

Thank you.. this basically means that if I have strong pressure coming out of the main faucet there is hope for a high pressure shower. Ok I have learned a lot so far...

I turned off all the power and opened it up but did not unscrew the wires but was quite concerned about the GRD slot being empty.

It it possible that there is another option for this being grounded or does this 100% mean it is not grounded?

I do not understand the whole grounded thing but think this is not good.

However I do realize now how easy it is for me to change my box should I want to buy a new one. Think I will try the vinegar trick first.

I did use the strong water in the out valve to try to flush it out but nothing came out. Indeed I think it is old and as it works the landlady is not keen to replace it.

[longball53098]

I agree about the safety of this machine. It appears to be an older unit and does not have the newer technology of the ELCB for cutting it off in event of a ground fault. And to make matters worse who ever installed this thing years ago did not follow even the simplest of pre-cautions that I'm sure were in the install book for this unit and that is a proper ground(earth). A good earth would provide some degree of protection if a short occurs in the unit. The way this one is connected you the user are the path to ground and possible death. My guess the electrical panel does not have a ground also and the breaker for this unit I would guess is also not the RCBO type or what we Americans call a GFI breaker

[lopburi3]

The original photo clearly shows ELCB at the bottom of unit so appears to have that protection so that should operate. But as indicated inside it must be grounded and it is not. Can not see if shower hose connection is plastic/ceramic or metal but hose appears to be metal. I would insist that unit be grounded or move out. As for flow it may be blocked but normal house water pressure here is much lower than western cities and point of use heaters will reduce that flow greatly as the normal heater acts the same a flow reducers used in the west to limit water usage (very small). Water flow is never as high feeling with these units as from tap. This is the primary reason we have installed pumps providing 60 plus PSI after many years with the normal Mitsubishi well pumps at 35 PSI. The pressure increase makes a big difference.

[powderpuff]

Beyond all the good advice given so far - really to diagnose the problem we would need to know the actual water pressure at your supply. A local plumbing or pump shop has the equipmet necessary. Most gauges are 1/4 inch NPT male & the supply is usually 1/2 inch NPT female.

So really you need only 2 items. A gauge rated to about 10 bar or 10 kg/cm; a reducer 1/4 inch NPT female X 1/2 inch NPT male & some teflon tape.

Close the supply to the heater. Remove the supply hose. Connect the hose to the gaude using the fittings. Might be useful to have some extra rubber seals. Report back here your supply line pressure.

Exact same rig in my condo under the kitchen sink:

Edited December 20, 2010 by powderpuff

[MisterMan]

Urg. I think I should by a new box. How does the grounding work. If i buy a newer box does a wire still need to be run from the box out to be grounded?

really clueless about these things but know that the missing wire is a bad thing for this box.

Not sure what my pressure is but it is quite good from a regular faucet.. very strong.

Any brand recommendations? Clarete seems to be in abundance but I bought a fancy fan from them and it is rubbish!

[lopburi3]

Have never seen that brand (Clarete). The Japanese have always been the major brands in such heaters sold here.

You must have a third wire for ground. And it must go to a real ground. In the unit it attaches to the "GRD" terminal in the power supply "L-N-GRD" strip.

A suggestion is to try another type of shower head. The feeling of flow can vary a lot with smaller number of smaller holes giving a stronger feel.

[longball53098]

Sorry I missed the ELCB in the first photo.

As I said before a ground needs to be installed at a minimum and the unit already has the ELCB.

Yes a ground(green wire) needs to be run to the circuit breaker box. But I'm gonna go out on a very weak limb and guess the CB box does not have a proper ground to a ground rod outside.

I don't see if the OP said if this is a single family dwelling or apartment/condo unit. This will make a difference in the wiring aspects.

The only way to know if the pressure/flow is being restricted is to test it with the suggested method. Just throwing money in to a new unit may not help.

[Pib]

The OP mentioned the flow out of sink spigot was "great" and the flow into the heater was "good" but the flow out was "bad." The words great, good, and bad can be very subjective.

With even low pressure of around 10 psi a person can still get the impression of fairly strong flow/strong pressure from a sink spigot because of the spigot's small internal diameter with screen on the tap which acts like a restriction on the very end of the spigot outlet, which is turn gives the impression of strong pressure. But if you only have around 10 psi coming out of an open-ended hose (no restriction) like goes into a heater it's probably going to "seem" like a lower pressure (compared to the sink spigot...maybe like "good" pressure).

By the time the water continues its journey through the heater where the internal pipes get smaller, the flow volume is going to be reduced quite a bit. On my two shower heaters, the pressure going in varies from 30 to 40 PSI from my water pump (a Mitsubishi WP-255) as the pump cuts-on and off....and I have a gauge to measure/confirm this pressure. With this 30-40 PSI range, or 35 PSI average pressure going into my water heater, if you take off the hose leading to the heater and turn the water on it is sprays out very strongly...I mean to where you think Wow!!! for a second...kinda like washing your car with good pressure coming from the water hose and the water can could shoot out for many feet. However, hook the hose to the heater and let the water continue its journey through the heater the water volume coming out is cut down to one-third to one half I'm guessing, but with the shower header on the outlet hose if fells like a very strong shower becasue the shower head is creating a restriciton at the very end of the flow output--kinda like the sink spigot. But the sink spigot is not having the pipes feeding it get way smaller in diameter like the heating pipe/elment within a heater. Yes, I know, I've also used some subjective words in describing the water flow but I have some good references in knowing my heaters are pretty new and the pressure going into them is averaging 35PSI / 2.5 Bars.

To the OP: recommend you have your water pressure checked with a gauge before you spend a bunch of money on a new heater because even a new heater is going to cut down the water flow quite a bit from input to output due to their basic design. My gut is telling me you probably just have low water pressure feeding your residence, and your sink spigot is fooling you into thinking you have great pressure. You are going to need a water pressure of approx 20psi / 1.4 Bar to get descent water volume out of the heater/shower head....getting up to around 30 PSI will be much,much better. Now, if you do come up with a gauge (they usually cost around 150 baht at a hardware store) and measure the water pressure going into the heater and it's 20 PSI or more, then it's probably indeed time to go buy a new heater.

[MisterMan]

Thanks this is most informative.

I live in a single house. Have just called the landlord and said things such as " mai dai tdor sai din" and "antarai"

(no wire in ground) (dangerous)

I'll start with the grounding.

Ok will try buying the gauge then to check.

(bum gun, outside faucet, kitchen faucet, all good though. ).

[Pib]

Landlord is probably thinking "crazy farang"......what you need a ground wire for, as the electricity flows perfectly fine just with two lines.

Also, since you said you live in a Single Family hose, do you also have a water pump. If so, what brand name and model is it? If you do have a water pump and it working properly then your pressure is probably OK, but you still need a pressure gauge to confirm. If the label is still on the pump it will probably also tell you the on and off pressures. If no water pump and you are just using water pressure from a water authority main line, you are probably just getting around 10 psi pressure to the house which is too low for good operation of a shower heater.

Edited December 20, 2010 by Pib

[MisterMan]

YEs I think she is thinking I am crazy also since I was moaning about the pressure. But once they put the grounded wire in I can change the box easily I think.

I am not really a man.. and all this is new to me with the shower boxes etc. But I am happy to learn..

We have well water and tanks, quite clean well water as I live in the base of hills with one one behind me.. I have no idea where the pump is.... her husband is a builder and the houses are nice and she does take good care of them..

Can i get a gauge at Home Pro?

[powderpuff]

Probably.

3 1/2 to 4 kg/cm would be nice result.

[Pib]

Maybe...seems each HomePro store has a noticeably different selection of products depending on local customer buying habits. I got my gauge at the Global House hardware store for 130 baht.

Since it sounds like you are probably a distance from the well pump, versus a pump being next to your house. That another indication to me your pressure could be low. From your description it sounds like your pressure may be determined more by gravity/height of the water tank above you versus more of a direct feed from the pump/pressure tank. The well pump may be just feeding/filling up a storage tank and then it gravity feeds down to the homes. How high above you home the tank is will determine your pressure assuming there is no pump taking water from the storage tank and pressurizing the water/feeding it to the homes.

Your problem could be similar to low pressure problems heard from some condo residences whose water pressure is basically determined by the storage tank on the top of the condo building with water pressure being determined by gravity/height versus a pump to increase the pressure. People on the lower floors usually get higher pressure than the folks on the upper floors due to physics/water column height. Kinda like diving in ocean...dive down 1 meter and the water pressure on you is about 1.4 psi (pretty low); dive down 10 meters and the water pressure is about 14 psi....dive down 100 meters and the water pressure on you is 142 psi. Basically each meter of water height above you will generate about 1.4 psi.

"Assuming" you only have a gravity feed system, if you had to guess how high above you the water storage tank feeding your home what would you guess? To get something close to 20 psi the tank would need to be at least approx 14 meters above whatever tap is running, excluding water pipe friction loss from the tank to your tap. But this is all conjecture until you find out more details on how the water is fed/pumped to your house and under what pressure. Cheers and good luck.

[MisterMan]

I think the tanks are below at a lower level.

But the good news is that I came home from work yesterday and both showers mine ( and the one in the extra bedroom/ bathroom) both had little wires running outside and down the side of the house in to the ground!!

Thank you!!!!!!!! Maybe you saved my life!! I probably would never have opened up the box!

Ok next step the pressure gauge!!!

Thank you thank you again!

[Pib]

I think the tanks are below at a lower level.

If they are below you then there has to be a pump somewhere; water don't flow uphill. Happy Holidays.

[doglover]

I think the tanks are below at a lower level.

But the good news is that I came home from work yesterday and both showers mine ( and the one in the extra bedroom/ bathroom) both had little wires running outside and down the side of the house in to the ground!!

Thank you!!!!!!!! Maybe you saved my life!! I probably would never have opened up the box!

Ok next step the pressure gauge!!!

Thank you thank you again!

Your most important issue was the grounding of the water heater and that MAY be complete. Your reference to the ground wire running down the side of the house and into the ground is worrisome however. But at least there is a ground wire in place however small or big it may be. The wire should be connected to a ground rod via a clamp that is supposed to be installed with the top portion of the that rod and it's clamp visible to all to ensure the connection is solid. Which should also be be painted with an acrylic paint to ensure the connection does not oxidize and come loose. The problem with local electricians is that it may in fact just be a wire stuck in the ground attached to nothing! If you notice the ground itself has been dug up around where the wire goes into the ground this connection may be in place just buried incorrectly. Of course the digging could be to just bury the wire attached to nothing a little better than poking it into the ground. The ground rods are not cheap and take extra work so I would do some investigating to make sure this has been done properly. Not advisable to shower with these units again until this is done.

Onto the pressure issues... I had the same woes with my unit. Yes the terms you used are subjective but when a farang says the pressure is good then it is probably sufficient so I'm going to run with that assumption . You have completed some of the steps already but I'll just start from scratch.

1. Turn off the electrical breaker supplying that shower unit. Ensure you have the CORRECT breaker by turning on the shower and the light comes on and then it will go off when you flip the correct breaker. If no light then check for hot water first and cool water after (but make sure your hands are dry before putting them in the breaker box!)
2. Disconnect supply hose from heater unit at the inlet point and direct away from unit. Open the water valve 100% and if the flow is spraying out and splashing off the floor with a WOW then pressure is good and there should be no obstructions. Now disconnect this hose and set aside.
3. Disconnect the shower head with its hose still attached to the shower head from the heater unit at the outlet point. Now connect this to you incoming water supply valve of the house water. Direct away from heater unit and open water valve 100%. If the flow out of shower head is now adequate for you and significantly greater than when you have it connected to the shower unit your problem is in the heater unit. If the problem is any hoses, valves or showerhead so far then break them down into smaller segments and isolate the obstruction.
4. Everything good so far then remove this shower head with hose, set it aside, and then reconnect the original supply hose to house water. Connect the other end to the OUTLET point on the shower unit and backflush the heater unit. (This is the point where the obstruction came out of mine and after reconnected everything it was as good as new). Now it should be mentioned the water flow restrictiction of my unit is a rubber seal at the supply side of the shower head hose.
5. After backflushing remove suppy hose from oulet and return to its original inlet position and replace the shower head and hose to there original position coming off the outlet. Open water valve 100% and if the pressure has improved you got lucky.
6. If there are still flow problems I would then proceed to remove the heater unit from the wall and follow Carib's (i think his name was) vinegar remedy for the calcium build up. This would be a good idea regardless seeing as you are using well water (unless there is a water softener installed). Not only will the calcium buildup restrict your flow rate but also the heating element will not function 100% effectively. Keep the soaking, draining and re-soaking process goint until there are no more deposits coming out. If there is calcium deposits coming out this may have been the issue.
7. Re-connect heater unit and hoses and try again. If still you still have pressure issues and have your WOW pressure from the house water supply then you are looking at buying a new unit. If you purchase a new unit ensure the wattage is the same as the previous model. If you want to upgrade the wattage you will most likely have to replace the wiring feeding the heater unit and the breaker protecting that wiring.

[Pib]

The wire should be connected to a ground rod via a clamp that is supposed to be installed with the top portion of the that rod and it's clamp visible to all to ensure the connection is solid. Which should also be be painted with an acrylic paint to ensure the connection does not oxidize and come loose.

I've always heard you "do not" paint the clamp & rod to ensure you can see the true condition of the connection and painting could interfere with a solid electricial connection. Just did a few googles which seem to confirm this. For example at web page: http://www.ehow.com/how_6082370_upgrade-non_grounded-house-wiring.html and notice the first Tips & Warnings near the bottom of the web page.

And paint ain't going to keep a clamp from coming loose. From my memory, I can't remember ever seeing a grounding clamp/rod painted in the US or in Thailand, not that I was walking around inspecting grounding rods. You sure about this painting thing?

Edited January 7, 2011 by Pib

[doglover]

The wire should be connected to a ground rod via a clamp that is supposed to be installed with the top portion of the that rod and it's clamp visible to all to ensure the connection is solid. Which should also be be painted with an acrylic paint to ensure the connection does not oxidize and come loose.

I've always heard you "do not" paint the clamp & rod to ensure you can see the true condition of the connection and painting could interfere with a solid electricial connection. Just did a few googles which seem to confirm this. For example at web page: http://www.ehow.com/...use-wiring.html and notice the first Tips & Warnings near the bottom of the web page.

And paint ain't going to keep a clamp from coming loose. From my memory, I can't remember ever seeing a grounding clamp/rod painted in the US or in Thailand, not that I was walking around inspecting grounding rods. You sure about this painting thing?

Well this is what we do in Canada anyway. I tried to check your link but my internet won't go there right now. The brand I have always used is Glyptal......

Originally developed as an insulating paint, this product is now commonly used as a primer, sealer, adhesive and protective finish. The outstanding resistance to corrosion, moisture, oil, acid, heat, dust and salt spray makes it popular for many uses, like;

• Electrical insulation for terminals, coils and armatures
• Anti moisture coating on thermostat, water cooler and truck control parts
• Primer for structural iron and steel
• General plant maintenance
• Sealer for concrete floors
• Primer and finish for motor, generator and transformer housings
• Sealer for pipe and stud threads
• Anti corrosion protection for winches and other outdoor apparatus
• Adhesive for gaskets
• Coating for interior of hydraulic tanks, and bearing cases.

In addition to sealing the connection from moisture and corrosion it prevents oxidization of conductor and clamp which is what could loosen the connection. The paint definitely does not work like a lock nut and the connection must be torqued adequately before painting.

For Thailand one could take a look at Crossy's site under the grounding section. Which is a great place to visit for the OP if they decide to purchase a shower unit with a higher wattage.

*Can't remember what the rules are with links but someone will shut me down if I've gone awry........ http://www.crossy.co...g/earthing.html

Edited January 7, 2011 by doglover

[Pib]

A cut and paste from the link in my post which referenced an article based on the US National Electric Code is below:

Tips & Warnings

• Ground rods can be made of ferrous or non-ferrous metal, and they should have no paint or other non-conductive material on them.

[doglover]

A cut and paste from the link in my post which referenced an article based on the US National Electric Code is below:

Tips & Warnings

• Ground rods can be made of ferrous or non-ferrous metal, and they should have no paint or other non-conductive material on them.

This is refering to the ground rod before the clamp and ground conductor are attached to it. It must not be painted BEFORE this is completed as most paint is non-conductive which would give a high resistance, something you definitely do not want with a ground connection. After all work is complete the painting provides the benefits mentioned in my previous post.

Edited January 7, 2011 by doglover

[Pib]

A cut and paste from the link in my post which referenced an article based on the US National Electric Code is below:

Tips & Warnings

• Ground rods can be made of ferrous or non-ferrous metal, and they should have no paint or other non-conductive material on them.

This is refering to the ground rod before the clamp and ground conductor are attached to it. It must not be painted BEFORE this is completed as most paint is non-conductive which would give a high resistance, something you definitely do not want with a ground connection. After all work is complete the painting provides the benefits mentioned in my previous post.

Makes sense. I did some more googling and found this links about grounding of a TV antenna which recommends painting of the clamp/rod connection point after installation of the clamp to help prevent corrosion..

Partial Quote:

Seal the exposed metal of the bolt with an epoxy sealant or metal paint. Metal-to-metal connections will corrode, and sealing them protects them from moisture.

End quote.

Read more: TV Antenna Installation Instructions: Grounding | eHow.com http://www.ehow.com/how_7727294_tv-antenna-installation-instructions-grounding.html#ixzz1APQ5WNOt

Then another web site about attaching a ground where it says first insure you are making metal to metal contact and then you can repaint to help prevent corrosion.

http://www.vias.org/wirelessnetw/wndw_07_05b.html

[jaiyenyen]

Something else you might like to check before you buy a new unit.

Check that the hose between the unit and shower head is clear. There is a plastic hose inside the metal hose, and they sometimes twist up, although the metal outer hose looks okay. I've came across this problem a few times back in the UK and was able to save my customers the expense of buying new showers.