10 year old boiler

Shemp

My house has a 10 year old Slant Fin steam boiler.

How long could I expect a unit such as that to last ?

Also, the mcdonnel miller water feeder got stuck open about 5 years ago and I've been filling it manually ever since.

I was thinking of getting it fixed or a new one. Is it really necessary? (my wife seems to think so if I'm away and she has to fill it).

I don't think its such a big deal.

Thanks

Rod

Boiler Age

Hi-  There no definite age limit on boilers. Slantfin is a very good boiler and seems to be longer lasting than most.  How long they last seems to be more defined by how well they are maintained and the water that is used to fill them. Some geographical areas (like eastern Massachusetts)  have very bad water from boiler's standpoint. 

As for automatic water fillers-  A lot of people specifically don't use them due the possibility of experiences like you have had in that they can fail and cause a lot of damage by flooding the home.

If a steam system is tight and doesn't leak, it uses very little water but even a small leak, like a leaky radiator inlet valve, releases a lot of water.

- Rod

Hap_Hazzard

Automatic Water Feeders

A water feeder is an emergency backup to keep your boiler from running out of water and shutting down if a leak develops. It should not be turning on on a routine basis. If it is, you need to find the leak and fix it. Aside from running the risk of flooding if the feeder doesn't shut off, you are shortening the life of your boiler by adding excessive make-up water.



Tap water is saturated with oxygen and other gases and may also contain varying amounts of dissolved minerals. When the water is heated, the oxygen and minerals come out of solution. Until this happens, the oxygen is free to attack the cast iron, causing it to rust. The net result of adding water over time is a weakening of the boiler walls and a buildup of of mineral deposits and rust on the bottom. This buildup makes the transfer of heat less efficient, so the outer surface of the boiler gets hotter when the burners are on, which not only sends more heat up the flue, but also adds to the heat stress and causes metal fatigue.



The advantage of adding makeup water manually is that you can add water only when the boiler is about to fire, but you should never add more than necessary to replace water flushed from the boiler or used to or blow down the LWCO, in addition to the negligible amount lost through venting.