Jack Lum 0 Report post Posted June 17, 2010 I had a Tecno instant water heater , model is TWH 48 or something like that, about 1 - 2 year, recently I found that when I turn off the tap, the led light still on for about half an min and then it went off. When I turn on the tap later, the water was very hot and even had steam. I only worry it may explode as it seem to heat even it is off. I off the power and took out the cover and checked, it looked alright internally, when I turn on the tap and off it, the flow switch did activated. Anyone know what is going wrong ? Thanks in advance. Share this post Link to post Share on other sites
bepgof 20 Report post Posted June 17, 2010 (edited) I had a Tecno instant water heater , model is TWH 48 or something like that, about 1 - 2 year, recently I found that when I turn off the tap, the led light still on for about half an min and then it went off. When I turn on the tap later, the water was very hot and even had steam. I only worry it may explode as it seem to heat even it is off. I off the power and took out the cover and checked, it looked alright internally, when I turn on the tap and off it, the flow switch did activated. Anyone know what is going wrong ? Thanks in advance. Seem some blockage in the flow which delays the flow switch from cutting out immediately. May be the membrance rubber get harden, or the arm of the limit switch get bent and distance change. Edited June 17, 2010 by bepgof Share this post Link to post Share on other sites
wolflet 1 Report post Posted June 17, 2010 i use to have this problem too. just have to lower the shower head to ease off some pressure in the system after turning off the tap. works for me. just make sure the shower head is lower than the heater level so water will start dripping out Share this post Link to post Share on other sites
Warrior88 0 Report post Posted June 17, 2010 My suggestion, DON"T on the heater now, just use the cold until the problem rectified. There were cases of explosion due to defective valve, pressure relief valve. The pressure in the tank it exceeding the relief point. Don't play play Get agent if still under warranty, otherwise get a new one. maybe less than 200 include installation. Share this post Link to post Share on other sites
Jack Lum 0 Report post Posted June 18, 2010 i use to have this problem too. just have to lower the shower head to ease off some pressure in the system after turning off the tap. works for me. just make sure the shower head is lower than the heater level so water will start dripping out Thks a lot , it seem that u are right. I lower the shower head and the heater function ok. Share this post Link to post Share on other sites
wolflet 1 Report post Posted June 19, 2010 Thks a lot , it seem that u are right. I lower the shower head and the heater function ok. back then, i suspected the back pressure of water caused the heater to be kept on. tried this method and it worked. but.. dunno if its what i thought anot? either way, if it works, its fine with me Share this post Link to post Share on other sites
pocus 0 Report post Posted July 20, 2010 My parent's 707 heater had this same issue after 1 year. Intermittent problem. Becareful, cos you power may trip. Temporary do not on the heater. Call for servicing ASAP. For our case, the serviceguy replace a faulty valve and problem is fix, 2 years liao the heater is still ok. good luck. Share this post Link to post Share on other sites
