What do to with boilers during the summer

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What do to with boilers during the summer

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MilanD

Great article! Thanks! We have a Weil-McLain LGB boiler, and I kept water in it over summer. Manual says it's ok to do so... sooo, I am wondering if there are any other reasons that they ask so, other than to prevent from someone starting an empty the system in the fall?I mean, low water cut-off will prevent this anyway... but if it happens to fail, water in the boiler will still make it knuckle-head proof, no? So, aside from preventing firing on empty, will it actually hurt the boiler to drain it down and keep it empty and dry in the summer (while turning off the power to it, and also gas valve, and to clearly label it with a sign NOT TO TURN IT ON until the water has been filled to the boiler)?

Second question regarding the city make-up water. If the boiler is drained in the spring, and new water is filled every fall, there will be new sediment and oxidation-inducing minerals introduced to the boiler, that will speed the deterioration and rusting of the system, (as you write elsewhere -- these mineral deposits will cling to and create issues with quicker rusting and burn-throughs on the cast iron -- deposits that will burn hotter inside the boiler wall and thus burning through the cast iron wall, etc).

So, which filter should be used for the city water to the make-up tank? I remember reading somewhere in one of your books/articles, you suggest getting a filter to the make-up water on a steam system. Will a regular, say 20-25 micron whole-house carbon filter installed at the boiler do the trick? Or 5 micron? Or is the reverse osmosis an overkill?

Regular whole-house sediment filters will remove any sediments and rust from city the water, or so it says on them. Coincidentally, I have one of them GE 25 micron at my house, and 8 years later, my 'new' 8 year old water heater is clean inside (I've drained it once every 6 months for a few years, to now just checking once a year). All our faucets' aerators have also not had a drop of calcium on them at all - ever, washing machine and the dish washer are clean of any deposits too, etc...

Back to steam: is a 25 (or 5) micron filter be enough?

Thanks Dan for bringing back all the knowledge over the art of steam heating. As a novice in this field (out of necessity), it's great reading and very fun too! I heard in one of your lectures you've been reading Pulitzer-winning books... If you haven't gotten to this one - it's worth a read, 1924 Pulitzer-winning autobiography of Michael Pupin. It's just amazing. I got a chuckle that he started his education, so to speak, in a steam-room of a cracker factory in NYC and ended up being one of the great American inventors and, taught math and physics at Columbia for some 40 years.

Cheers!

Steam

In regards to steam boilers: If you have isolation valves on the main steam piping, this will allow you to keep water in the boiler up to the stop valve/s during the off season. I would recommend you treat your steam boiler water with say steamaster tablets, you can keep good water in the boiler and not have to worry about completely draining and refilling every season.

MilanD

Thank you for the answer. We don't have isolation valves. There are zone valves with actuators attached, but 3 of 4 are not operational and are always open. I suppose these could act as isolation valves and I could try to detach them and turn them by hand to close, although this may be moot point as they are probably rusted in place by now. There is also a condensate tank which too is open to atmosphere and it too is a concern.

Thus, the question remains if it would hurt the Weil McLain boiler to completely drain it during the summer, or how much oxygen it actuality absorbs in the summer to make it really matter via off-gassing and evaporation into the pipes during the summer months (afterall, this is a 1922 system and pipes are still doing their job - with a pin-hole leaks once in a while which get serviced and/or pipes replaced). I am more concerned with protecting the boiler itself and having it last as long as possible.

Second question would be if using a house filter like the GE GXWH04F with a 5 micron sediment filter be sufficient to remove enough of scale before the water boils to help it out with any make-up water. With all the traps serviced the boiler shouldn't be using much of make-up water, but again, it's cheap insurance to have the filter there.

Finally, - it cost us about $20,000 to get the LGB 7 installed, and replace the failing LGB 11 which also stood idle for 7-8 years while the building was vacant, but lasted another 16 years after it was put back in service, with minimal if any annual servicing done before I got here. So, I'd like to keep this new boiler going as long as possible (now 7 years in service). I understand that with a little bit of proper maintenance, this boiler could last another 50 years.

And, just a little bit on the install: we had an engineer from the boiler supplier come by and calculate loads by counting the radiators, etc - in essence, doing the correct calculations per what Dan preaches, and were sized to LGB 7 for proper volume and steam load. We had no issues with heating since and even before I knew to service the traps, our fuel consumption has decreased. I will be curious to see how we do this winter now that all traps are operating at the optimum.

About zone valves: I did read one of Dan's notes on zone valves on steam systems, and them having issues with water trapping in the 'zone' causing hammering when open in the middle of the boiler cycle. On the one zone we still operate, there is no such issue and here is why I think this is: 1. all piping is pitched correctly with highest point being right above the boiler, and 2, on the 2.5 inch supply side pipe, right after the riser turns 90 into the zone loop itself but after the zone valve, there is a 1 inch 't' facing towards the floor, piped to 90 reducer to 1/2 pipe and into a Hoffman 17c trap, and on to another reducer (or enlarger?) back to 1' pipe, and back to the condensate tank from there. The one zone that works has never had issue with water hammer or extra water being trapped causing either excess make-up water to the condensate tank or hammering. Everything just drains as it should by gravity, and both the start of the loop and the end have traps that seem to function as they should (17c on the beginning of the loop and Hoffman 56 FT + Warren Webster 78 at the end of the loop). I am curious what Dan would think.

I am writing a bit more here in hope it helps someone else with these questions. These old steam systems are a testament to human ingenuity, being so simple yet brilliant, and functioning so well and on same principles 100 years later. They need to be maintained, and should be maintained as historically significant pieces of technology - when man successfully defeated the cold. Keeping these systems going is simple, does take some time and knowledge, but is not too demanding once everything is running the way it should. Getting the traps serviced and replaced as needed is a must to get the system to work properly, yet is so simple that anyone who played with legos or has replaced a kitchen faucet should be able to do it.

Fred

@MilanD , you don't need isolation valves to overfill the boiler in the spring/summer if that's what you want to do. Those who take that approach simply fill the boiler until the water is up a few inches into the risers. You can feel where the water level is with you hand. If you do so, run the boiler just until the water starts to boil to burn off any excess oxygen in the fresh water added. The intent of over filling is that rust through typically occurs at the water line where moisture and air are both present. It's less costly to replace a piece of black iron riser piping that a boiler. I would say most of us don't over fill our boilers, nor do we drain them for the season. Draining them leaves the entire cavity exposed to rusting.
Because rust-through often happens at the water line where the cast iron is exposed to air and water, I typically change the water level in my boiler every summer. I will raise it up an inch or two or lower it down and inch or two so that the water line isn't the same every year during the idle seasons. I don't know if that approach actually helps waterline rust-through but it doesn't cost anything and my boiler is now 34 years old and still going strong (knock on wood). What ever you decide to do, when adding fresh water, bring it to a boil immediately to burn off that excess oxygen.

MilanD

@Fred - Thanks Fred for all the tips and explanations! Filling the boiler a few inches above/below operating water line (and alternating from year to year), boiling it off and leaving it like so is a great suggestion and makes a ton of sense. Not being lazy, I just got off the phone with a guy at Winstel Controls from whom we bought the boiler and who's one of the more knowledgeable people around here (from what I can gather by talking to others in the mechanical business here). He said the same thing - fill it a few inches above the regular water line. I'm waiting on the 'white paper' from him, that was published recently by Weil McLain and that deals with our area in particular, something to do with our water being particularly corrosive and what the manufacturer recommends. I read Dan's stuff on this very thing happening in upstate New York somewhere, with steam boilers failing every 7-10 years.

Anyhow, yours is a great suggestion - to alternate water level from summer to summer. I will also install the water filter mentioned below. This should help with water quality as well, and shouldn't have any adverse effects. Less scale is always better!

Filling the boiler into risers is also a great idea! My only issue with this is that our pipes are 4 inches and that I have 3 risers that are 4 inches. As I am looking how that's piped, should any one of those pipes fail it'll have to be replaced by way of hammering and breaking the old cast iron elbows, replacing them and then using union flanges. It would definitely still be much cheaper and easier than a new boiler install, that's for sure.

So, I'm weighing the options and what you mentioned seems to be the way to go.

Here's one curiosity: our old LGB 11 boiler (the one before this LGB 7 was installed in 2010) was abused - literally - by not being serviced, drained, blown down weekly, etc... Our traps were bad until I realized something was off last spring and serviced/replaced them all. Conclusion: we had plenty of new water added over the years to both the new and old boiler... And with all this, the old boiler functioned for 15-16 years, after previously sitting idle and filled for 8 years before that (thus freezing and thawing over 8 winters with water in it), and working from probably the early 80s to about 1988 before that. So it gave some 30 years 'service' under the most severe abuse. I have a feeling your boiler will last for a while longer too, Fred, if you are doing everything you are be doing.

I am now happy to know that the attention our new boiler will be getting will definitely make it last for a while.

One last note: I cleaned the burners this fall too. There were in good shape, some superficial rusting on the outside and soot inside. After cleaning it off on a bench-grinder mounted brush, I applied a thin coat of oil on all the burners to protect them from corrosion (kranoil and bp blaster - it's what I had on hand). My dad was a mechanical engineer and I remember him explaining to me when I was a kid - to protect metal, any oil is better than no oil. I will be curious to see what they look like next fall.

Thanks again Fred!

Steam

I installed my steam boilers myself. I added main steam stops, and also condensate stops on both boilers to isolate one from the other.

Also, if there is a leak anywhere in the return, I can evacuate the return line water without draining the boilers. Plus the condensate return valves isolate different sections, because a leak might be either upstream or downstream. Although I replaced the return lines, maybe it would have to be a worry in another 30 to 50 years from now.

Having the main steam stops allows me to fill the boilers to the stops, without worrying about any water going into the mains and staying there.

This is an above and beyond approach, however, the added costs aren't that great. Most people only have one boiler for their house....I have two. I also keep a boiler log and fuel usage log for my heating plant........err boiler. There's only one thing I would change, and that would be to increase the size of the main, but the system heats fast, operates at ounces of pressure and is reliable so I don't think I need to bother.

In your case, I would definitely follow Fred's advise as his setup more resembles yours. All the best of luck to you, and here's to many more heating seasons.

MilanD

@Steam

Thank you for your note. I will definitely do the water level alteration next summer. I would love to see your install and setup pictures. I am attaching a few boiler riser pics of ours.

I also installed blow-down valves on all zone returns' drip legs as I discovered them filled 100% solid with 50+ years worth of stinky hardened sludge. I did the same in overflow pipes to those Hoffman 17c traps that are at the start of the zones (which I mentioned in one of my earlier posts on this thread). These Hoffman 17c traps were not piped with drip legs, so after servicing them and discovering they too were filled with sludge, I repiped them with some "t"s and created drip legs on them with blow-down valves at the end. This way I can blow things down from time to time, which will, hopefully, extend the life of our Hoffman 56 F&Ts, Warren Webster 78s and Hoffman 17cs, keeping the dirt out of them. We have 4 F&T traps, 3 warren webster 78s, and 3 Hoffman 17cs. The replacement kits were quite costly for all of rhem.

On balancing side I have also replaced all the main vents with new Hoffman 75 main vents, and I installed various new rad vents: larger capacity made-o-mists farther from the boiler, and on the rads closest to the boiler I also installed air vents with thermostatic actuators which shuts those rads off as soon as the room gets comfy. I also added a brand new vaporstat and a new low-pressure gauge to the boiler controls. The system is now well balanced and running on 10 oz of pressure max with every last radiator getting hot quite quickly.

Steam: it's a thing of beauty.

Thanks again for your input! Here's to many more cozy and warm winters!

Steam

Beautiful setup. I just finished lagging my boiler with fiberglass insulation and lagging cloth. I am going to paint it and also add some rivet heads on there to give it a nice old school look. Just deciding the color combinations. Trying to decide on Red and black, or maybe black and gold would I think would be perfect, which I'm really leaning towards. So the boilers are not ready to show just yet. But I will definitely send along some pictures when everything is done.

I'm also pondering a decorative tin ceiling for the boiler room. Which would be my winter project. I know, I should put it in the kitchen first, but I've been wanting to tin the boiler room ceiling for a while.

MilanD

Thanks! We are lucky that the Masons built this building, and in 1922 when this was done, it was done right. Piping, zoning, sizing, pitch... As luck have it, no one touched it after the Mason's sold the building and for the most part, only repairs done were in replacing pinhole leaks here and there and some radiator valves.

This one has one zone (of 4 in total) that is completely counter-flow, only one pipe going up to rads in the attic. The same pipe is then taking the condensate all the way down to the boiler. You can see it in the front facing picture, on the upper left. There is one 1 1/4 "t" right as the riser turns into that zone, and that's where the condensate drops down into an FT trap and moves away from the steam. This zone is now not used, as no one is living in the attic. There is a sag in that pipe somewhere buried in the ceiling between 2nd and 3rd floor, as when the system is on there is some serious water hammering in the ceiling after the first heating cycle. It happens in that ceiling somewhere and I am assuming we have a tight elbow with a sag somewhere that seriously narrows the pipe. That will be a project for someone else. I had a forced air installed for that space, in case it's needed. No sense firing 780,000 BTU to heat 800 Sqft.

It's funny listening all you are saying. I have forced air at home, and I would so love to install a steam boiler and radiators. I just love the heat from those 212 degree radiators. There is nothing as comforting in the dead of winter.

Please do share the photos when you are done - it would be awesome to see.

All the best!

stevenknaub

Can someone provide a checklist that details how to drain a steam boiler that sits idle for most of spring, all of summer and a month of fall?
Should the boiler water be saved and reused? (Mine holds less than 10 gallons, so two 5 gallon buckets with lids would prevent contamination).
Should the drain valves be left wide open?
Should the steam vents on the radiators be removed?
My idea is to prevent as much rust and corrosion as possible