1 Steam Cars : Phorum
General Steam Car topics
Water issues
Posted by: Lonny Claypool (IP Logged)
Date: October 24, 2003 11:23PM
<HTML>I am new the the forum, and I have been reading some of the discussions and I hear alot about boilers, engines and such but I am wondering what thoughts might be out there about water used in the boilers. I remember when I was younger my father had a model that my grandfather built of the pottery where he was the stationary steam engineer. Long story short, we used to show the model at the Roseville-Crooksville pottery festival and always had to bring water from our well at home. The city water provided at the parks just seemed to take forever to boil. The model's boiler was a replica of 24 fire tube boiler at the Robinson Ransbottom Potter in ironspot (where I grew up). I am wondering if anyone else has had issues with water? Does boilers work better with distilled water?</HTML>
Re: Water issues
Posted by: SSsssteamer (IP Logged)
Date: October 26, 2003 04:20AM
<HTML>Dear Lonny, Water whether at home or else where, it will take just as long to reach a boiling point in a pressured vessel. At higher elevations, there is a shortage of oxygen that slows the fire a little bit. Distilled water would be nice to use but it's ph level is 7.0 and because it is so close to an acid level, it is corrosive to the boiler if it is left stored in the boiler. A ph of 10 is a lot more safer to use in your boiler. I use TSP (tri sodium phosphate) available at any hardware store to treat our boiler water because our water is naturally at about 8.0 Some water is so heavy in minerals, that if not addressed, they will accumulate in your boiler and the minerals will eventually insulate the fire tubes from the fire. This will result in a mud burn. (leaking tubes) While on tour, I try to avoid home dug wells which usually have hard water heavy with calcium and other minerals. I prefer water out of the lakes and streams instead. Always blow down your boiler after a day's run to get rid of the mud that has accumulated on the bottom of your boiler. The condensing steam left in the boiler will turn to distilled water that will help melt the minerals from the inside of the boiler and they will be blown out during the next blow down. I usually don't blow down below 100 psi, and I try to stop my blow down as the last bit of water leaves and there is just steam blowing from the blow downs.</HTML>
Re: Water issues
Posted by: Lonny Claypool (IP Logged)
Date: October 26, 2003 08:58PM
<HTML>Thanks for your response, I wondered what steamers used on their runs. I am, as you probably are probably aware, a bit of a newbie to this old technology. I realize that the boiling point of water is as you say the same everywhere, but my perception at that time, as well as others working with the old boiler, was that city water just didn't seem to work as well as the well water we got from home. What you say makes perfect sense and I wasn't aware of distilled water's adverse properties. I hope to make steam engines a hobbie of mine. My brother inherited the old model my grandfather built and his son let the boiler run dry and you can guess the rest. We have been talking about building or having a new boiler but I want to study the process before we just start throwing something together that looks like the one my grandfather built. He was an expert, we are not and I am not foolish enough to think that I am. I am going to try to find some expertise here, maybe a mentor in our area to help. Thanks again for your insight.</HTML>
Re: Water issues
Posted by: Mike Clark (IP Logged)
Date: October 27, 2003 08:37PM
<HTML>The July Issue of “The Steam Car” had an article by Monty Goding, a professional in the design and operation of industrial boilers, which covered this issue of water quality.
Monty feels that the accumulation of dissolved solids in boiler water is as serious a problem as hard water scaling. Dissolved solids are salts which, when concentrated by distillation in the boiler, make the water surface unstable so that frothing and priming occurs and sight gauge readings become unreliable. Driving a non condensing car for a day’s tour of, say 120 miles, without blowing down could easily cause a ten or twelve fold concentration of dissolved solids, bringing them up to danger levels. In modern static boilers it is usual to have a continuous blowndown of up to 25% of the water going through the boiler simply to get rid of these dissolved solids; obviously this is acceptable on a static system with efficient heat exchangers but hardly practical for us. It would seem to be a good idea to blow down almost to empty at the end of the day but inconvenient to do any worthwhile amount of blowing down during the run. We should be aware of the increasing chance of misleadingly high sight gauge readings as the day goes on. It is actually possible to taste these salts in the blowdown water after a day’s run and have you noticed how much the sight gauge level drops as soon as you park and shut down the burner?
Monty also commented that it is better to use stream and pond water since this is not too far from rain, and much less likely to contain salts and scale forming compounds than mains water which is often taken from deep boreholes having spent thousands of years absorbing minerals from the rocks. If you are concerned about picking up grit with the siphon a small carburettor air filter (mine is from K&N) can easily be adapted to the suction hose. Monty also made the very useful suggestion that a water softener unit from a scrap dishwasher could be used to treat water being put into the tank and then regenerated with salt at home. It will take the full rate of flow from hose or by siphon.
Finally we have discussed previously the best way of storing the boiler over winter, full, empty, dry or whatever. I put some central heating corrosion inhibitor into the boiler which was then filled to overflowing. I did the same last year and in Spring it drained out absolutely clear with no rust in the water. Auto antifreeze would no doubt do the job but my workshop never freezes.</HTML>
Monty feels that the accumulation of dissolved solids in boiler water is as serious a problem as hard water scaling. Dissolved solids are salts which, when concentrated by distillation in the boiler, make the water surface unstable so that frothing and priming occurs and sight gauge readings become unreliable. Driving a non condensing car for a day’s tour of, say 120 miles, without blowing down could easily cause a ten or twelve fold concentration of dissolved solids, bringing them up to danger levels. In modern static boilers it is usual to have a continuous blowndown of up to 25% of the water going through the boiler simply to get rid of these dissolved solids; obviously this is acceptable on a static system with efficient heat exchangers but hardly practical for us. It would seem to be a good idea to blow down almost to empty at the end of the day but inconvenient to do any worthwhile amount of blowing down during the run. We should be aware of the increasing chance of misleadingly high sight gauge readings as the day goes on. It is actually possible to taste these salts in the blowdown water after a day’s run and have you noticed how much the sight gauge level drops as soon as you park and shut down the burner?
Monty also commented that it is better to use stream and pond water since this is not too far from rain, and much less likely to contain salts and scale forming compounds than mains water which is often taken from deep boreholes having spent thousands of years absorbing minerals from the rocks. If you are concerned about picking up grit with the siphon a small carburettor air filter (mine is from K&N) can easily be adapted to the suction hose. Monty also made the very useful suggestion that a water softener unit from a scrap dishwasher could be used to treat water being put into the tank and then regenerated with salt at home. It will take the full rate of flow from hose or by siphon.
Finally we have discussed previously the best way of storing the boiler over winter, full, empty, dry or whatever. I put some central heating corrosion inhibitor into the boiler which was then filled to overflowing. I did the same last year and in Spring it drained out absolutely clear with no rust in the water. Auto antifreeze would no doubt do the job but my workshop never freezes.</HTML>
Re: Water issues
Posted by: Dick Vennerbeck (IP Logged)
Date: October 28, 2003 04:11AM
<HTML>Lonny,
Try measuring the temperature it takes to boil one gallon of water at your location and then perform the same experiment after adding 1 cup of salt to one gallon of water. I think you will find that the salt water (added minerals) will have a higher boiling point. (The same occurs with sugar while making jams and jellies) Mike and SSssssteamer are correct in stating that you want the least dissolved minerals in the water. They can form deposits on the waterside of the tubes and reduce the thermal transfer efficiency...sometimes with disasterous results. My guess is that your boiler failure occured, by a total LACK of water situation. Most little hobby boilers will not be used enough for the operator to be concerned with the water quality. However you must pay strict attention to the water LEVEL, failure to do this may cause a nasty explosion in your kitchen.
Good Luck.
Dick Vennerbeck</HTML>
Try measuring the temperature it takes to boil one gallon of water at your location and then perform the same experiment after adding 1 cup of salt to one gallon of water. I think you will find that the salt water (added minerals) will have a higher boiling point. (The same occurs with sugar while making jams and jellies) Mike and SSssssteamer are correct in stating that you want the least dissolved minerals in the water. They can form deposits on the waterside of the tubes and reduce the thermal transfer efficiency...sometimes with disasterous results. My guess is that your boiler failure occured, by a total LACK of water situation. Most little hobby boilers will not be used enough for the operator to be concerned with the water quality. However you must pay strict attention to the water LEVEL, failure to do this may cause a nasty explosion in your kitchen.
Good Luck.
Dick Vennerbeck</HTML>
Re: Water issues
Posted by: Lonny Claypool (IP Logged)
Date: October 29, 2003 10:21PM
<HTML>Thanks for the info Dick. The failure of our boiler was directly caused by a young boy not watching the sight gauage and allowing the boiler to run dry. It He was very lucky that the boiler split on a weld seam and didn't explode. Unfortunately the boiler was a small piece of family history which cannot be replaced. My brother and I plan to build a new one as soon as we get a better handle on what that entails. I have a basic handle on the theory, but I have never actually tried to put it into practice. I have no doubt that we can duplicate what was there, but I want to be sure what we do is safe. I plan on tapping into some local expertise on the subject. I only raised the question on water because of my own experience years ago when my father and I ran it. I knew that the chemicals in most city water will change its characterisitics and I was curious as to what you all as experts used in your boilers. The answers have been most enlightening.</HTML>
Re: Water issues
Posted by: Arnold Walker (IP Logged)
Date: October 29, 2003 10:52PM
<HTML>Your steam expert might able to help you ...check for a fusible plug and
figure how to resheet the boiler.......assuming corrosion or something else
hasn't set in the valves checks,etc..you maybe running alot sooner and cheaper than a new built boiler.</HTML>
figure how to resheet the boiler.......assuming corrosion or something else
hasn't set in the valves checks,etc..you maybe running alot sooner and cheaper than a new built boiler.</HTML>
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