Hi; I have a great Weil-McLain gas hot water boiler that is going on 20 years old. I have it serviced every year by the very reputable firm that installed it. I am aware of some rattling noises that are intermittent when the boiler kicks on. Is this normal? The mechanic said that when it got really noisy it was probably time to install a new one. How noisy is too noisy? Any danger signs? I can't afford right now to replace it - my mechanic said new ones are about $8K. Any suggestions?

Thanks!

Weil-McLein is one of the best boilers on the market. The noise is could be do to mineral build up in the boiler over the 20 years you have had it. That is just a guess as I am not the one hearing the noise. This causes poor heat transfer to the water.

20 years is a good life expectancy for you boiler and shows that you have taken care of it. It is best to start planning on its replacement. May be not this year, but in the next few years. They always seem to fail on the coldest night of the winter.

The good news is that today’s boilers are more efficient then they were 20 years ago and it will also help in the sale of your house should you decide to sell.

Now some service companies will suggest “Acid Cleaning” the boiler to dissolve this build up. While this may work on a new boiler, this also can open a can of worms and do more damage then good for your boiler. I would stay away from that.

Kind of like the guy that put drain cleaner in his stopped up sink only to find that after the drain was clear, he had leaks all over the place. The blockage was also blocking up the leaks.

Yep, Wow is Right. Number one killer of water heating appliances is mineral deposits.

Best method is total replacement of the tank, elements and perhaps the adjoining plumbing pipe.

Modern tanks are more efficient, and its all around cheaper (in the end) to replace.

I would suggest inspection of all radiators in the house as well, mineral deposits in hot water circulated lines (not so much the steam type lines) accumulates and reduces efficiency of the radiating elements.

Overall reduction of tank and radiators can have a huge impact on the cost to run the critter in 20-25 years. Fuel/electricity to heat the water slowly goes up in the amount over the years as the tank/boiler builds up an insulated layer of scale. Depending on the starting efficiency and the cost to run at optimum, you could be burning hundreds of dollars per year just to get around the scale build-up.

Since your hearing noise now its time to start saving up for a new system (hope for the best, plan for the worst). Plan on 5 more years for this system since you are maintaining it. I do not know how hard your water is, it may be closer to 3 years than 5.

During the next 5 years consider alternatives, shop around. Since this is not an emergency you are not being forced to make a choice which could be the 'wrong' or more expensive choice.

You might also want too consider treating the water before it goes into the boiler. I've seen systems that treat (soften) all of the water in the house and ones that only treat the water for say a boiler or the hot water tank. http://www.energysolutionscenter.org/boilerburner/Eff_I...s/Water_Softener.asp gives some information on softening water.

Of course tests on your water should be done to know what kind of water treatment would work best for you water.

There are a lot of choices: http://www.weil-mclain.com/products/list/1-Gas-fired%20boilers is a good start since you have already had faithful service from the company.

Be mindful when you shop around, there are recalls on products: http://www.cpsc.gov/cpscpub/prerel/prhtml08/08566.html.

Of course you have been running on a boiler up to now, you might want to consider the more expensive overhaul to forced air. There are pros and cons to both, and differences in efficiency: http://ths.gardenweb.com/forums/load/hvac/msg0219084310777.html

Also consider what powers the system. If for instance you live in an area that has hydro-electric power you might want to consider going electric over gas or oil since electric costs will be regulated more by the dam than by the price of oil/natural gas.

Right now you have a lead time, you have time to consider a lot of options and to set aside money - if not the full price, then a substantial down payment that will open the doors to more expensive systems.

Hating cooling adds to the value of the house if you plan on selling it then having a better/newer heating system becomes a selling point. If you plan on staying then you need to consider the long term costs of running the system - how much fuel it takes, what the estimated fuel costs would be.