Another Dandy

Al Roethlisberger

I hear ya, and I'm not even a pro.

Hate to say it, but it doesn't seem too rare =(

I've visited a few of the remaining installations of steam or hot water in my residential area, and they seem to often be very much patch jobs at best. My conversion was especially poor it seems.

Although to be fair, my conversion was done DIY by a homeowner that didn't have the benefit of resources like this back in 1991. But he did have "consultative" assistance from the old town plumber/pipe-fitter that maybe should have known better. But our locale had really lost its hydronics professional expertise by then I think. Now it is non-existent.

But miraculously my system ran "OK" for about 15 years, although it doesn't surprise me that they system never worked "quite right" and had enormous heating bills.

Some of my issues that have been or are being corrected:

- Boiler installed "backwards"
- Used standard boiler "package" of side mounted circ, no effort to size circ appropriately, and pumps toward expansion tank
- Used water heater(212F/150psi) relief on boiler, no down tube. If it popped(boiler would have likely split by then),that hot water would have shot sideways.
- no air control, no air vent on system, no air removal, no airtrol on expansion tank, tank incorrectly attached. Hence water logged, and many air problems.
- tridicator long since broken. No way to tell temp or pressure.
- aquastat high temp at 200F

That's just what I can recall off the top of my head =/

The prior owners ran system in this state, wondered why water leaked past valve stems, enormous bills, uneven heat, etc..

...and of course there is no pri/sec or any other type of flow management or boiler protection. The boiler is just hooked directly into the old supply/return.

I really can't believe(and thank goodness) that the system didn't explode or just blow huge leaks everywhere over the last decade. I'm also glad that the "bad experience" previous owners had with the system didn't cause them to abandon it or rip it out.

Fortunately it looks like nothing broke though, and the necessary fixes(safety already done) are in the works.

I guess some folks just don't care, or know to care...

Al

Unknown

Looked at this today,

great boiler, but no P/S, or bypass "period" on this system.
This installer drove quite a piece to get the sale, too bad that`s all he knew how to do!
Typical,, will they ever learn???

Dave

Mike T., Swampeast MO

I daresay that there are tens if not hundreds of thousands of cast iron boilers driving converted gravity systems without primary/secondary or bypass for decades with no sign of problems from condensation. Even with full outdoor reset! This includes "modern" low-water content plain cast iron boilers.

As long as you install TRVs, converted gravity systems are very well-suited for use with a mod-con with a single circulator and no form of primary-secondary. A differential pressure bypass valve must be installed though.

Worst thing I see is that modern compression tank. Unless that's a VERY small gravity system it is far too small. System pressure likely rises considerably as the system heats and there's a good chance you find that the pressure relief has been "weeping".

jp_2

all that I have seen

in these parts, no primary/secondary piping. all cast iron boilers. I have seen a ball valve across supply & return, I guess that kinda counts.....

Unknown

Well Mike,

right or wrong,,at least I gave you something to look-at LOL.

Dave

ALH_4

Oversizing the boiler

Oversize the boiler enough and you dont have to worry as much about flue gas condensation.

I can hear it now... "You figure it needs 100,000 btu/h? We better use a 200, just to be sure. Better to have too much than too little."

Mike T., Swampeast MO

No problem Dave. Just because such systems do their job of heating the space properly without harming themselves, does not mean they do it efficiently...

The system in my own home was nearly identical. In addition to greatly improving the thermal performance of the shell, I added "extras" such as reset, bypass, warm-weather shutdown, constant circulation and TRVs in an attempt to improve efficiency. Each helped--but other than the improvements to the shell, they were all baby steps compared to adding a mod-con even though the existing 1970s cast iron boiler probably had decades of life remaining.