My replumbing project

[warno]

The end of last season turned into a nightmare at best. Over heating issues led to cavitation issues. I couldn't get enough heat out of my boiler to save it from going into idle mode, No matter what I did. Some of you may remember my threads on over heating and cavitation from last year.

So fast forward to now. I've made many changes. Cut my head losses by more than half, went to a bigger FPHX, and went to induced draft.

I went back in my old thread to try to find my head loss numbers on both sides of my old FPHX but could only find the boiler side. Last year I was running almost 20ft of head on the boiler side. This year I've cut that side down to less than 5ft. My storage side this year is going to be about 14ft and both sides I did the math based on 10 gpm.

Pictures...

FPHX old vs. new

Storage side plumbing old vs new

Boiler side plumbing old vs new

Induced draft setup

I still need to add length to this pipe to get it up in the flue a little more.

I still need to tidy up the wiring, it's all hooked up for testing purposes at the moment. I need to put another piece of foam over the front of my FPHX and a cover plate. Planning on firing it up soon, hopefully things run alittle better now.

 

[maple1]

Good luck!

 

[TCaldwell]

I think your ready for the fluegas analyzer!

 

[jwise87]

I can't get over how clean your builds always look.

 

[maple1]

I wish I had the ability to fab up s/s piping like that. And not just for a boiler. Sure cleaned up nice!

 

[warno]

I think your ready for the fluegas analyzer!

I actually didn't change much on the internal parts. I'm still running the fire side like last year other than induced draft vs forced combustion.

 

[maple1]

Interested to see how that inducing works out. Think most or all I've seen have involved a fan in the actual exhaust stream. Which I would think would require some pretty clean exhaust.

 

[cumminstinkerer]

I am as well @maple1 I tried that theory a long time ago on a homemade wood furnace and it didn't work well for me, but that also had about 18 feet of 6 inch insulated chimney at the time, I finally converted to 8 inch and that helped it. I really hope it works well for him then I will incorporate it into my next build , a downdtraft gasser, @warno will definitely be getting lots of texts when I get around to starting that project.

 

[warno]

I wasn't sure how to demonstrate the draft inducer or how to check if it was pulling vacuum in the firebox even. So I turned the fan on and cracked the door. It was most definitely pulling vacuum through the firebox. So I made a cheesy little video here. I lit a leaf on fire and put it in the primary air pipe that comes in from under the fire. You can see little trails of smoke coming from the end of the pipe indicating it's pulling air in the primary pipe even with the door open. Then I shut the door and it sucks the leaf out of the pipe and it's laying in the ash pan.

Again I know it's a cheesy video but it's proof of concept.

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[jwise87]

What problem are you trying to resolve by switching to induced draft? What are the benefits?

 

[maple1]

One major one is getting rid of smoke spillage.

 

[jwise87]

One major one is getting rid of smoke spillage.

You mean there is an option other than smelling strongly of smoke every time you add wood?

 

[maple1]

You mean there is an option other than smelling strongly of smoke every time you add wood?

Yessir.

 

[warno]

What problem are you trying to resolve by switching to induced draft? What are the benefits?

I was hoping for what maple said and also I was hoping it would allow me to better control my incoming air. With the fan blowing into the fire box the only way to lessen the air flow is block it which in turn starts making amp draw go up in the fan which in turn burns up fan motors. I was hoping to be able to push full stream of air up the flue pipe then I could throttle back my inlet airs without over amping the fan.

But it turns out with the preliminary fire tonight my draft inducer isn't up to the task. I don't think I'm getting enough CFM up the flue to create enough vacuum in the firebox. The fire was really lazy like it was lacking air flow and it would pick up when I cracked the ash door. Tomorrow I'm going to try a different fan with more CFM but if it doesn't work I'm abandoning the induced draft setup and going back to the old way.

 

[warno]

So it turns out the induced draft doesn't work. I went as far as piping my leaf blower to the flue pipe and running it on high. It worked better but not good enough. I'm abandoning the concept and going back to forced combustion. Hopefully I can get to a point where I can at least test the new plumbing. And hopefully it works better than my luck with induced draft.

 

[BoiledOver]

What are you using for your forced draft? The forced draft blower on this Eko boiler is variable speed which is controlled in steps of ten, we can go from 60% to 100% through the main controller. In conjunction with a rotary dimmer, dialing in a sweet spot is very easy.

 

[jwise87]

Did it at least suck the smoke out the stack when opening the door?

 

[warno]

What are you using for your forced draft? The forced draft blower on this Eko boiler is variable speed which is controlled in steps of ten, we can go from 60% to 100% through the main controller. In conjunction with a rotary dimmer, dialing in a sweet spot is very easy.

That's basically what I friend of mine did on his boiler. That's going to be the next thing I go to once I get the old forced setup put back in.

Did it at least suck the smoke out the stack when opening the door?

It would with the door about quarter of the way open but with the door fully opened it would still smoke back.


I have a bad habit of changing too many things at one time. I should have left the firing process alone from what I had last year. It was working fine.

 

[cumminstinkerer]

@warno as we were discussing last night about my two fans, the secondary one that gets noisy at low speeds is a different style than the one you have in your pictures, my primary one looks very similar to the one in your pictures, I like that style better and they seem to handle more static pressure, I am going to switch the secondary to the better style when I move stuff to put my storage in. I'll have to reroute my intake piping and move the blowers due to the height of the tank so I will just switch that one out when I do that. hopefully soon now that I have my diesel back and can pull my gooseneck I can go get the tank, was hoping to this weekend but a family friend/ buddies grandpa died and funeral is saturday so that messed up all my plans for the week.

 

[warno]

I have my primary and secondary fans switched back around. The ducting and wiring is less than appealing but they are running and it's made a world of difference going back to this setup. I have one more piece of pipe I need to cut out of the fire box that I added in but as of right now it's doing good.

 

[warno]

So same dilemma as last year. Fire burning hot and I can't get the heat out of the boiler fast enough. Everything is purged I'm running 40° house spigot water through the storage side to fill my tanks. And the boiler is only dropping about 11° for a delta T. The pump is still cavitating on speed 3 even with it being practically on the ground. On speed 2 it quiets down but for whatever reason I can't get a high enough flow rate to cool my boiler down.

One option I'm considering is taking out my small turbulator and sending more heat up the stack instead of into the water.

 

[cumminstinkerer]

@warno hey man send me a pic of where your circulator is in relation to the boiler and or storage, I'm just getting ready to leave work in a couple minutes so then I will be able to get it. I'll do some thinking while I clean my fire tubes.

 

[maple1]

That's 11° on speed 3?

How/what is the storage side doing?

 

[Woodman1]

Sorry if I am way off on my observations as I have only glanced at these threads the last year, but my thoughts are 11 degree delta t screams lack of flow. The thought of trying to divert heat up the stack seems counterproductive. Is this system pressurized?

 

[maple1]

More apt to be all kinds of flow. Slower flow usually means bigger dts.