The Glade 4.0

So my tank is about 40 years old. There are two elements, at 240v, rated at 3kw.

One element tests at 36-38ohm - about right for half the rating, 1.5kw
One tests at infinity - figure its burnt out.

Sound right?

Figure I therefore need to replace the element. The corrosion is pretty bad though and Im afraid the bolts might shear getting it out, leading to no heating at all, where right now with just one element the thing still sort of kind of works.

Any advice?

Just the obvious - replace it.

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In time, this too shall pass.

Go tankless?

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This cold and dark tormented hell
Is all I`ll ever know
So when you get to heaven
May the devil be the judge

It's a tankless job, but someone's gotta do it...

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In time, this too shall pass.

Personally, unless it's unique and hard to replace...I would just replace the thing and not worry with trying to repair it.

You can find one for around $250 at Lowe's. Just don't forget to get some pipe compound...

40 years old it likely has corrosion in the tank, the thermastats might need replacing, and/or both elements......if not now, eventually. The only good thing you might find in one that old, is it might have a copper liner which they don't make these days iirc.

Make sure you fill the new one before turning it on

As for tankless......if it's electric.....I wouldn't worry with that. More expensive to buy, probably would have to do some extra work to hook it up (electrical and/or pipes).....and from what I've read, while they save on energy they don't put out the same as the tank type. It supposedly takes several minutes to get the hot water to the faucet, and in the case of dishwashers, sometimes they don't produce enough pressure to trigger the water heater.

SuiNeko might have a hard time shipping it back to London for a reasonable price Sam, London, England.

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The U. S. Constitution doesn't guarantee happiness, only the pursuit of it. You have to catch up with it yourself. B. Franklin

"A mind needs books like a sword needs a whetstone." -- Tyrion Lannister, A Game of Thrones

Welp, in that case.....guess I can't be of much help.

It was my first thought too, well just go down to Home Depot or Lowe's and pick out an upgrade. But you know, I really don't know what the DIY home repair shops are like over there, and what the rules are. I don't imagine it would be much different than here (other than the shop names), but you never know.

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The U. S. Constitution doesn't guarantee happiness, only the pursuit of it. You have to catch up with it yourself. B. Franklin

"A mind needs books like a sword needs a whetstone." -- Tyrion Lannister, A Game of Thrones

Replacing the tank means rebuilding the kitchen to get to it ... ;(

That sucks, but with a 40 year old tank, it's likely going to be one of those situations where you suck it up and do it now, or suck it up and do it later after it ruptures. The latter is a lot messier, though you might be able to make a claim on your insurance. If you have neighbors below you, they will hate the latter as well...

Other option might be to have a plumber in to at least evaluate it, they might even be able to do a replacement without having to demo the kitchen.

Assuming the two elements were connected in parallel, if they were both originally 36 ohm loads, you're looking at a 3200W draw for the entire unit.

This raises the question - are the individual heating elements rated for 3kW and 240V, or is that the entire unit that has that rating? I assumed the unit was 240V and 3kW.

What I'm inclined to think happened is one of your heating elements oxidized, which caused its resistance to spike. As its resistance climbed, it heated up faster, causing it to oxidize faster - you get the idea. I don't know the construction of your house, but I find it difficult to believe that it's impossible to replace your water heater (which I assume is the device in question) without demolishing the kitchen. It might be a little tricky to pull off, and require more plumbing expertise than you personally possess, but there has to be a way to do it. I would advise calling a plumber and getting an estimate.

You really should replace the unit. The failure that burned out one element is probably lurking in the future for the second. It's only a matter of time before you have to replace it, anyway. You're also operating the unit at half capacity, which I would imagine isn't entirely friendly for your energy bill. Furthermore, there have been a lot of advances in both the electrical and mechanical sides of heating and cooling in the last 40 years. Whether you're heating water or air, units are a lot more efficient. What this means is you'll be replacing your old unit with one that costs less money to operate.

Finally, buy local. People suggesting Lowe's and Home Depot have overlooked the fact that you're British. Different countries use different signals for electrical power transfer. http://en.wikipedia.org/wiki/Mains_power_around_the_world

Wall outlets in the United Kingdom are 230V RMS at 50Hz. As you can see from the table, wall outlets in the U.S. are 120V RMS at 60Hz (though we actually broadcast 240V from power stations, and have 240V wall outlets for large appliances). The real problem is the frequency. An American appliance designed for a 60Hz electrical signal fails spectacularly (i.e. goes boom) when plugged into an outlet receiving a 50Hz signal. There are adapters available to convert the 50Hz signal into a 60Hz signal, but frankly, save yourself some headache and buy stuff designed for British outlets.

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Buckle your pants or they might fall down.

We installed a tankless water heater in our first house. While convenient and theoretically energy-saving, the whole "instant-hot water" thing didn't come to pass as I expected. Unless you're using hot water all the time, every time you turn off the hot water and don't use it for a while, it cools down. So, you still have to run the water for a while, just like a regular faucet. Our dishwasher worked fine. It was a Japanese model, a Noritz. But, you could take a five-hour hot shower, if you wanted. My wife liked the idea of never running out of hot water.

But, for ease of use (and because they're already more popular in Europe, no?), I thought he might give one a try. Wouldn't have to rip up the kitchen, at least, although they usually have to be vented directly outside.

Here's your local Home Depot, Sui.

Google Maps - Home Depot in Southall

_________________
This cold and dark tormented hell
Is all I`ll ever know
So when you get to heaven
May the devil be the judge

Besides the potential disaster that a 40 year old water tank is, newer models are likely to be far more efficient...