Placement of Secondary float LWCO

vaporvac

There are two PROBE-type LWCOs on my twinned Slantfin TR 5os . I have manual feed for water replacement. If one wanted to add a seconday float-type LWCO as a safety backup where exactly would one put it and does one then clean it out as per usual? To me one of the advantages of the probe-type is NOT having to do the weekly blow-down, but in the event that I need it, I'd just like to be sure it goes in the correct place.



Also, if a back-up is required can this be a another probe-type? It would be nice to elimate the blow-down completely,

EBEBRATT-Ed

Secondary

I would think the secondary would be at the lowest permissible water level & yes it can be a probe type. Secondary is usually a manual reset if a secondary is required by code. If it's just put on as a back-up and not code required I would think manual reset is a good idea but may not be required.

vaporvac

One ore two?

Thank you. The code requirement is a bit murky, but i just want to be prepared. Plus, i like having back-ups. Is there any place on the lines where I would only need one extra instead of the two I would need if putting them on the actual boilers? Somewhere on THe Wall i thought I saw one piped like this.



If not, o the boilers themselves I only have the open tapping where the float type would go. I presume this would be the spot since it is lower than the probe tapping.

nicholas bonham-carter

Lwco location

Usually the float type LWCO is plumbed into the sight glass. I'm sure there must be some instructions online which would show that better than I can describe it. If you have a vacuum, then there will be difficulty draining the LWCO, as incoming air will keep the water inside it. Only when you can see positive pressure can you test it.

When is your system going into final countdown?--NBC

vaporvac

Thank you for asking.

I would prefer the probe type so it's good that i can use it. The picture I saw might have been a Steamhead installation and it was on piping by the wet return?and Hartford loop? It was a twin boiler installation, but i can't find the pic.



Anyway, it's been a VERY hard (and cold) few weeks with many disappointments. The commercial installers who were supposed to finish it next week (really as favor for a friend) decided yesterday that they don't want to do a residential job. .after two weeks of being told they just need to find time. I understand, it's just the time wasted. However, my plumbing suppliers remembered my install and recommended probably the one installer I haven't yet spoken to. (Noone else would finish a boiler started by someone else.) I believe they're coming Monday or Tuesday to hook it all up. They haven't seen it yet so I hope they don't have a freak out over the twin install like the other companies that came. That's an exaggeration, but they really just shook their heads at the whole set-up. Is it that bad? It made me feel like it was totally jacked up.



I'm playing around with the controls in case I have to explain how they should go and am buying the unions, and other bits and bobs that will upgrade the control install. In the end, I'm having to get this thing going all on my lonesome. I can talk a good game, but it's a bit intimidating. My hat's off to everyone that does this for a living.

JStar

Steam

Don't be discouraged. It's the supply houses and the contractors that should be ashamed! You're doing a great job, and the right job. Keep at it and you'll have a happy steam system when it's all done. Your story is a testament to the sad state of our industry today.



Check out the photo on one of our twin jobs that shows where we would put the 2nd LWCO. We install the common return manifold up at least 6" so that there is always water in the boilers if the manifold leaks, and to make swing joints for easier installation.



Try to avoid putting a LWCO in the equalizer or Hartford Loop. There is a lot of bubbling in those lines that will give a false reading. Found that out the hard way!

nicholas bonham-carter

Preparing for the installers

Why not print up pictures of all the twin boiler setups which have been described here, so you can show them to the installer when he comes to have a look. That way, he will see that you are following in the footsteps of others (" hey dude come on, everyone's doing it!"), and not doing something completely off the wall, and never done before.

What exactly remains to be done? It seems you have most of the piping done, and only lack the burner setup.

It might be better to avoid confusing them with the taco setup, and just explain the cycling on pressure of the lag boiler. Later when all can see how it works, the taco switcher can be added.--NBC

vaporvac

Excellent ideas...

Those are GREAT ideas(s), especially the one about leaving the Taco for another day. Might make more sense.

Today, I strung up the new wiring that needs to be attached into the main box. There is a dedicated outlet, it just needs three wires instead of two.

To be done by a professional:

connect wire to box.

wire in spill switches and burners

wire in probe LWCOs

wire in pressuretrolls and gauges

wire in vaporstats and original vacuum gauge.

For the very near future: wire in two-stage Tstat and Taco relay.

Help me start them up and do the combustion analysis.



All piping and venting is done with the exception of the control header. It was just a dry run. I'm actually taking pipe and wrench in hand today to get that done which is surprisingly engaging. I am also taking apart the old vstat fo be able to put in the ball valves and unions. I have to wait 'til tomorrow to buy them as the big box stores don't carry that small a size. I want the professionals to focus just on the wiring of the controls and burners.



I'm hoping with the great tutorials on the wall to be able to do the cleaning and skimming myself. Slantfin also gives quite complete instructions for that. Obviously, I'll need to insulate the near boiler piping and bit of main we re-routed and a long run in the garage that was never covered. (I guess they always left the ceiling rad on for the Chauffeur.) Then, I'll go around fixing all the things that leak , such as valves and check out the orifice situation if I can't find replacements for mine, and try and figure out why one rad and the pipe leading to it is generally stone cold. I also need to take off the one vent someone erroneously put on a rad which is under a built-in cover/bookcase. Fun stuff!



I'm adding the extra LWCO to the Summer Boiler To-do list which is growing exponentially!. I really like Jstar's install; it's very clean looking and I thing doable with my current return configuration.



thanks again for all these super suggestions! colleen

nicholas bonham-carter

wiring controls

you might do a better job of wiring the controls than the experts. multi-strand wire is so much easier to use.

I think you are just hours away from heat!

just remember to look at the gauge as it first fires up to see what the back-pressure is, so you can set the cutout of the lag boiler just slightly above that value.--NBC

vaporvac

Apparently Four hours to heat!!!!!

The steam guy has booked four hours to get my system up and running!!!!! I DID mention the two-stage Tstat and Taco relay and his response was, "That's what you need if you have two boilers!" So I think he can go ahead and put that in. In any case, a fellow Wallie has offered to do a rough wiring schematic for me. Wallies are THE BEST! He 'll also hook up the electric to the breaker box and finish the piping on the control header if I don't finish it. I will believe this is all real when I hear the lovely sound of steam coming up in the rads.

I just got the 1/4" unions which were NOT easy to find. The nice store owner remembered me and stayed open while I dashed to get them.



Question: I hear you often talk about the back pressure., but don't understand WHAT that is or HOW to measure it. Thank you everyone.

nicholas bonham-carter

The light at the end of the tunnel

Make sure you have JStar's diagram, as the new installer is probably thinking of 2 hot water boilers, and in the case of steam, it's probably a little different, because of switching the lag vaporstat control wiring every other time it fires. If he has trouble, just leave that bit until later.

The back-pressure I refer to all the time is a measure of the resistance of the air to being pushed out of the system, whether 2-pipe, or 1-pipe.. If it is very low, then the air is able to escape easily, and if it is high, then the air has to be forced out by burning extra gas. In your case, there will be some natural resistance to the air escaping, and it think, that value is where the lag boiler can stop firing, after it has reached that pressure and pushed the air out of the air eliminator (2-6 ounces). As a vacuum is established in your system, the back-pressure will not really be a factor, until the shoulder season where enough time may have elapsed between calls for heat, that the vacuum may have dissipated.

Thinking about the controls for a 2-boiler vacuum system has me waking up at 4am, and doodling over a cup of tea most nights.

I can see from the SlantFin heat loss app, that my chapel system can maintain a temperature which is 40 degrees above the outside with only one of the two boilers, but when the temperature drops below that, I will need the lag boiler to fire again. This will be controlled by the vaporstat, so as the temperature drops, with one boiler working, it will not be able to maintain an adequate pressure in the system, and the vaporstat will allow number 2 to fire.

The part I am thinking about vacuum is operation during warmer winter weather, when the lag boiler may not need to fire at all, even to get up to the 2-6 ounce pressure. In this case, maybe a warm weather shut down sensor could prevent the lag boiler from firing at all in merely cool temperatures.--NBC

vaporvac

wiring...???

That's interesting NB-C. So are you going to have a two-stage Tstat? If not how are you going to wire the Vstats to get them to toggle? I only have a wiring diagram for the Tstat thus far.

 It never occurred to me they might think it's a WATER boiler. I'm pretty sure I said steam, but I also had one contractor almost order me an Intrepid h2o, until I went a different route.

So now that I understand back-pressure how do I measure it...just whatever I see on the pressure gauge?

Hopefully, I'll have heat this time tomorrow. I should have time for the initial cleaning and then wait a few days for the skimming which is what most suggest. Just in time for another round of COLD temps. I almost don't remember what it's like NOT to wear a coat indoors. The funny thing is that now I find normal temps to be WAY TOO HOT!

p.s. I can so identify with thinking about these boilers in the middle of the night. I would often wake up and sketch a piping diagram or jot down an improvement or question. What will I do with my time now?!!! Hah...maybe clean.

vaporvac

Venit ,,.Vidit ...Ivit

In other words no heat and no light at the end of the tunnel. Just having a cuppa while pulling myself together from this disappointment.

The main reason was they had never installed a gas conversion burner and didn't want to start now, especially since it needed the orifice switched out with another one (that's supplied). The control header threw them for a loop, but I said to feel free to install a pigtail if they want. They completely misread the Vstat instructions for a "remote" placement, but I would have just had them put them on the boilers. Then there was the vapor issue which has come up before. There's some belief that EVERYTHING has to be different since it's vapor. Oddly enough the twin system and staging didn't phase them at all.



They did complement the neat piping job (nice to know it's looks decent), and the unions on the pressuretrols.,but after hanging around reading the burner install manual, they said NO. I asked them to at least wire up what they could, but they again said NO (which I guess i understand). One of their recommendations was to another company that had wanted to rip out my system for HW or at least put some traps in it, so I'm calling their other suggestion.

I think they also weren't too pleased having to come out after the big 4" of snow, but it's getting cold again. and I just have to keep trying to find someonewilling and able.

So they came... they saw... they left...after using my bathroom.

nicholas bonham-carter

Hopefully they lifted the seat!

That's the sort of thing I was worried about, especially here as gas, or oil burners are very few and far between.

It looks like the Riello instructions are written to be clear and simple. Maybe you will have to go it alone. I did see the section describing the diaphragm selection, and changeout for whatever firing rate you would choose, and it does not look that hard initially. The final adjustments will have to be made using the combustion tester.

Here are my thoughts for the 2-boiler control: a 2-stage thermostat will energize the lead boiler first, and if the temperature continues to fall a degree or so, the second stage of the thermostat will fire #2. Vaporstats for each boiler will limit #1 to 4 ounces max, and for #2 2 ounces.

The aim is to keep #1 running at sub atmospheric pressures as much as possible, without firing #2 unnecessarily (unless the temperature is dropping sharply). One boiler should be able to handle the heat loss when there is only 40 degrees difference between the outside and inside.--NBC