Water Heater: Fuse Wire Fuss

I have a Horstmann Electronic 7 Maxistore water heater in my home an

I've been having fuse problems as of late. We've been living here fo about 7 months and never once had a problem but the other day I went t disconnect a storage heater and had to cut off the main power. When turned it back on, the 15 amp fuse wire for my water heater blew. I was merely broken but I went out and got some new 15 amp fuse wire an replaced it. A few hours later I hear a loud pop and when I switche off the power and checked the fuse box the wire was completely gon except for the melted bits attached to the screws. Again I replaced i and again it happened. Fuse completely melted and gone. Is too muc power flowing through? Is it safe to use a 30 amp wire? Any help woul be much appreciated. Thank

-- Tim W.

Not familiar with your particular water heater, but if you turned off the power, and somehow the water level got low...did someone turn off the water supply as well?

In that scenario, the upper element of a normal U.S. style water heater might blow out...causing the exact symptoms you describe. Perhaps the element blew from thermal shock of being powered on while immersed in cold water. It shouldn't, but since it's old....

In any case, something's wrong. You ABSOLUTELY SHOULD NOT replace the fuse with something larger! In fact DO NOT replace the fuse again! You'll have the same result. There's something wrong, and since you obviously do not have the technical knowledge to troubleshoot--much less repair--the fault; I'm afraid that you need professional help.

Diagnose and fix the problem before you cause a bigger problem, like a fire.

jak

NO! Absolutely under no circumstances use a higher than rated amperage fuse! You will very likely set the house on fire and insurance will *not* cover it. Find out what's wrong with your water heater and have it fixed.

The failure sounds like an intermittent short. Could be a heating element or something external. But absolutely agreed you should not run it until the cause is determined. Whatever happened the first time could have just been a tired fuse. But when it happened again, and by the description, rather violently, there is definitely something very wrong.

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Firstly, don't replace the fusing with anything but the proper rating.

Secondly, you should give more details when you ask for help.

I suspect that from your email address and the make name that you are in the UK and that this is a tankless point of delivery water heater. We had these damn things in the Bahamas when I used to live there and they were prone to developing leaks in the water coil directly onto the heating elements and blowing fuses.

Regards Lee in Toronto

Where are you? Down under? My guess - you have a bad element - may have a crack in it. Don't up the fuse rating. A 1500 W heater on 230 V is 13 Amps. Don't exceed 15.

N