Easy fix for my shower heater?

[FarangFB]

My electric shower heater worked fine for 2 years and then started to sometimes not turn on the heater. 

 

It has a green light that is always on and a red light that comes on when it's heating water. Over the past few months it became more and more rare to get the heater working (red light wouldn't come on and water would come cold), I had to repeatedly close and open the water valve until I got the red light, sometimes taking more than 10 attempts to get it working.

 

 

But since yesterday I can't get it on no matter what I do. Already tried the reset button.

 

Is this a quick/easy fix that I can do myself or do I need a new unit?

 

 

 

Edited March 10, 2019 by FarangFB

[tutsiwarrior]

when you have checked for any flow obstructions local to the heater unit (inlet filter, shower head, etc) think about any other demand on the water supply upstream of the heater unit, other showers in the house, etc...our house is at the end of a municipal water distribution system and I usually shower between 10pm and 3am as that's when I'm sure that most neighbors upstream will be asleep with all the taps off so that there's plenty of flow to my house...the water flow cools the heating unit and if it's not sufficient it won't work...the arrangement protects against heating element material failure from overheating...

 

 

[Crossy]

As above, mesh filter on the inlet, shower head. I'll add collapsed flexy inlet pipe, they can go yukky after a while.

 

Does the flow appear to be less than in the past?

 

[Formaleins]

20 hours ago, Arjen said:

Sounds like a clogged waterfilter, or not enough water flow....

 

Mostly they have a small build in filter somewhere at the inlet. First check this.

 

Arjen.

I'd go with that, some have a pressure switch some have a flow switch - my old 10KW National could make you a cup of tea, but my new one - National, virtually identical but 8KW is not a patch on the old one, it appears to have about three different sensors, flow, temperature and pressure. (the other thing that might be worth checking depending how far along the pecking order from your nearest transformer is - would be your voltage.) Before we had a new supply to the village, my supply was almost the last in line from the nearest transformer, then it had to run over another 200-230 metres before it hit the distribution panel. If there was a high demand from the village, my supply voltage would often drop to as low as 150VAC. You tend not to bother checking as a lot of things like the new TV's etc. will run on anything over about 120VAC, so it appears that you have electric, whereas a lot of devices simply will not power up at that voltage.

Edited March 11, 2019 by Formaleins

[Kerryd]

Most heaters are set up quite similar, varying mostly in size and style.

When I have heating issues it is almost always due to poor water flow. This could be from the main water supply feeding your house/condo/apartment, or from a dirty in-line filter or clogged shower head. (If the water can't get out, it backs up the system and the flow rate detector inside the heater will shut off to prevent the unit from overheating.)

Some systems will have a small plastic inline filter just before the heater (lower-left corner of the pic). Make sure the water is turned off and then unscrew that little plastic cap. The filter is a part of the cap and comes out when you've unscrewed it. Sometimes it can get clogged with flakes of rust or dirt from the water.

  

 

Some shower heads will unscrew off of the handle. Try taking the head off and checking if the holes are plugged. It may be possible to clean it using a brush and by running water "in" through the holes (instead of "out" like the water normally comes out). If the head doesn't unscrew, try slapping it against the palm of your hand a couple times then turning on the water and see if that loosens any debris up. Don't bang the head on anything hard or it could crack (or whatever you are hitting could crack, like bathroom tiles).

Check the inlet hose. Unscrew it and let it drain. Note if the water coming out is dirty or "rusty" looking. Those hoses are usually of a cheap quality and rust a lot quicker than you'd expect. Turn the water on and check it for colour as well. Often after we've had a water "outage" here, it's because someone broke a pipe somewhere (usually doing roadwork) or they've done it on purpose (maybe adding another line or something) and when the water comes back on, it can come out very cloudy from all the dirt and crap that entered the line.

Reconnect the inlet hose and turn the water on. Note if there is any leakage from the hose, indicating that it may have rusted through in spots. Those are cheap and easily replaced - literally every little mom & pop hardware shop stocks those.

 

I recently replaced the heater for my bathroom sink because when the village switched from it's own water to the city (or province) water, the pressure wasn't the same and the heater wouldn't turn on no matter what.

I bought a different model and it works fine. Love the one I installed for the kitchen sink. It keeps heating even when I have the tap turned down to barely a drizzle. I do that when I want to mop the floors as the water is literally steaming when it comes out. 

If all else fails, it could simply be the heater inside the unit is fritzed and you may have to replace the whole thing. Save that for the last resort though as it could be something simple and easy (and cheap) to fix !

[Kerryd]

Also - if your unit has one of those in-line filter gizmos on it, check that the "flow rate valve" (or whatever the **** it's called) is "inline" with the hose as pictured:


Turn the water on and then turn that white knob (whichever way) and see if the water flow increases. "Off" isn't "off" as the water still flows, but there is a noticeable drop in the flow coming out of the tap. (This is the unit I installed for the bathroom sink - I like hot water when I shave.)

It doesn't take much to reduce the pressure entering the heater and with some of them, even though it looks like you have lots of water flowing, it's not quite enough to trigger the heating element.

(And I have tried taking the old unit apart to adjust the "flow rate detector" - which turned out to be a sealed unit and not worth the effort to try and take apart and put back together again.)

[Jeffrey346]

Had the same problem. Turned out to be the thermostat. Had it replaced and all is well.

[xtrnuno41]

As described an inlet can be blocked, but also as Jeffrey said, could be a thermostat or even one of the other sensors. Wiring can be bad, corroded. You will see green (copper) black (molten plastic) or Brown (iron) should be metalish. Your box is in a moisturised area and should close off totally , but ......

ALso a very tiny leakage inside can cause moist and therefor corroded connections or switches (sensors)

For the thermostat, you can put on the water and then switch the thermostat several times, mostly you leave it one point. 

If a heating element is burnend, it also doesn t work, the red light will remain out. In a beginning it can switch on by sparks internal, it is "welded" together, it connects again, then getting cold and break again, until it has gone too far and it can not connect anymore.

In cases of powerdrops as i red (wow from 220V to 150 V), the thing wont work either

Otherwise you ll have to open the box, to see. FIRST :Be aware to shut off the power before opening

[millymoopoo]

If you have the type of tap pictured, these are inevitably cheap local made zinc, not brass ones and as such corrode and will restrict the flow in the same way as a blocked filter.
Worth checking and if corroded, replace with a brass one.

[mikecha]

opening the cover turn main power off  canbetemprementalswitchsensor if touch could get a surge  is your earth fitted correctley   this can cause a fault toalso the O is tight

[Pib]

My water heater is a 6000W model comprising of two 3000W heating elements each with a 16A micro switch.  When you turn on water and the flow is adequate the pressure switch/valve engages the two 16A microswitches which applies electricity to the heating elements...the little red light comes on....I have hot water.  About every 2 to 3 years I have to replace one or both micro switches because the switch contacts become defective.   If just one of the two switches goes bad I only get 3000W of hot water heating...if both switches goes back no heating....and no red light.  But I've never had both switches go bad at once....just one.  When one needs replacement I just replace both....easy to change.  The switches cost approx  30 to 75 baht....I get them at Amorn Electronic stores....or you can order them online.

 

[sawadee1947]

Buy a new one, mate. Or what is your problem? 

You need funding. It's popular at present 

[finnishmen]

my first water heater work fine 1 month then stop working, i looking has water pressure too low, simple repair, i hooked pressure microswitch one wire and then work well next 3 year. but burn one day broken and now has buy water tank and pump and good pressure and new heater, work well. and old hongnaam have new low pressure heater now.

[Chrisdoc]

Sounds like a clogged waterfilter, or not enough water flow....
 
Mostly they have a small build in filter somewhere at the inlet. First check this.
 
Arjen.

Yes had that problem. Replaced it and the same. Found a clogged filter on the inlet hose. Works great now.

Sent from my Nokia 2 using Thailand Forum - Thaivisa mobile app

[Pdavies99]

6 hours ago, Kerryd said:

Most heaters are set up quite similar, varying mostly in size and style.

When I have heating issues it is almost always due to poor water flow. This could be from the main water supply feeding your house/condo/apartment, or from a dirty in-line filter or clogged shower head. (If the water can't get out, it backs up the system and the flow rate detector inside the heater will shut off to prevent the unit from overheating.)

Some systems will have a small plastic inline filter just before the heater (lower-left corner of the pic). Make sure the water is turned off and then unscrew that little plastic cap. The filter is a part of the cap and comes out when you've unscrewed it. Sometimes it can get clogged with flakes of rust or dirt from the water.

  

 

Some shower heads will unscrew off of the handle. Try taking the head off and checking if the holes are plugged. It may be possible to clean it using a brush and by running water "in" through the holes (instead of "out" like the water normally comes out). If the head doesn't unscrew, try slapping it against the palm of your hand a couple times then turning on the water and see if that loosens any debris up. Don't bang the head on anything hard or it could crack (or whatever you are hitting could crack, like bathroom tiles).

Check the inlet hose. Unscrew it and let it drain. Note if the water coming out is dirty or "rusty" looking. Those hoses are usually of a cheap quality and rust a lot quicker than you'd expect. Turn the water on and check it for colour as well. Often after we've had a water "outage" here, it's because someone broke a pipe somewhere (usually doing roadwork) or they've done it on purpose (maybe adding another line or something) and when the water comes back on, it can come out very cloudy from all the dirt and crap that entered the line.

Reconnect the inlet hose and turn the water on. Note if there is any leakage from the hose, indicating that it may have rusted through in spots. Those are cheap and easily replaced - literally every little mom & pop hardware shop stocks those.

 

I recently replaced the heater for my bathroom sink because when the village switched from it's own water to the city (or province) water, the pressure wasn't the same and the heater wouldn't turn on no matter what.

I bought a different model and it works fine. Love the one I installed for the kitchen sink. It keeps heating even when I have the tap turned down to barely a drizzle. I do that when I want to mop the floors as the water is literally steaming when it comes out. 

If all else fails, it could simply be the heater inside the unit is fritzed and you may have to replace the whole thing. Save that for the last resort though as it could be something simple and easy (and cheap) to fix !

Okay, so you want an easy fix....turn off electric power!!!!  Very very important!! Then take the unit off the wall, so that the water inlet is at the top and pour in some Kettle descaler and leave overnight, next day re-assemble and turn on, keeping out of the water and it may clean it out! (This works most times!) Failing that get a new one!

[myshem]

Hello, related question, what is surprising is that even when water has a  lot of limescale, the heater still works very well after many years, almost 10. Is there an explanation for this ? Does heat breaks stones ?

 

Thanks.

[Kerryd]

3 hours ago, myshem said:

Hello, related question, what is surprising is that even when water has a  lot of limescale, the heater still works very well after many years, almost 10. Is there an explanation for this ? Does heat breaks stones ?

 

Thanks.

From my experience, as long as the unit is getting sufficient water flow (pressure) it will keep heating. It could be that the limescale can't build up inside the heater/pipes enough to block the flow or reduce the pressure. I haven't had one running as long as yours though so I can't say for certain !

If you notice a reduction in the outflow or start having problems with it not heating the water, I'd suggest trying the method described pdavies99.

(Or buy a new one.)  ????

 

[FarangFB]

Thanks for all the replies. Mine doesn't have the filter like the photo, but I think the problem is probably one of the small pipes right at the intake.

 

There is a little thing in there that moves up when there is water flowing and a sensor on the side that detects when it's up and turns on the heater. What I believe happened is some dirt is making it hard for the little thing to move up even when there is water flowing.

 

I tried cleaning the inside of the pipe with a cotton bud and now the shower works around 20% of the time I try. If it stops for good again I'll try a more serious cleaning, thanks for the support.

[FarangFB]

Update: after attempting to fix it myself and getting soaked and electrically shocked I decided to call a Thai handyman. He checked it (got soaked too in the process) and said I needed a new unit.

 

I went to Homepro and I forgot how hard it is to buy what you actually want in there. It happened already when I tried buying an electric drill. Every time you try to pick a brand you know, an annoying employee will try as hard as he/she can to make you buy some unknown brand saying it's much much better and cheaper. 

 

There is absolutely no way to be polite and get what you want in less than 15 minutes. They simply don't let you take the brand you want in a friendly way, it took me like 20 minutes of "no thank you, I want a brand I actually know" before I "was allowed" to pick the damn water heater I wanted. Seller was trying to push me some Thai brand I never heard before, saying whatever nonsense she could come up with to make me change my mind.

 

Finally I got the unit I wanted, brought the guy in for installation and he said the way the wires were done (without a circuit breaker) were very dangerous. No wonder I got shocked, that breaker I turned off wasn't connected to anything. He added a breaker and it's all good now.

Edited March 18, 2019 by FarangFB