Am I in danger of killing my whole family by poisoning from outdoor wood burning boiler water contamination?

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docdoc

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Hey folks - I posted this in another thread, then I found out the last response to that thread was in 2010 (oops). So here I'm posting afresh:

I bought a home in May 2021 with a Brute Force (I think 5800) wood burning outdoor boiler. Worked great last year. This year, also keeping us toasty. However, this year, one of the blower fans gave out (and shortly after so did the solenoid). I have replacements on the way; however, the reason the motor went out (I think) was due to a short caused by the power cables running into the motor having the sheathing exposed, and the copper wire touching the metal door. This short caused the ETC to get bypassed, and the top blower stayed on. I didn't notice until my wife pointed out the "smoke" (it was steam) POURING out of the vent cap on the top. When I went out there, the water was rolling off the pitched roof of the boiler unit everywhere. Temp was at 220 F!!!!! Water was boiling over! I got it under control.

The vent cap has the float arm to indicate FULL, SAFE, and REFILL levels. I believe I'm still in the "safe" zone; however, I need to know how to fill this puppy up (especially at end of season, as I also have flush and water treatment on the way with the replacement parts).

I believe the previous owner has a set up where the ground well water (from the pressure tank in the house, of course) runs into a heat exchange plate, then into the water heater. In line with the water source is a T-connection that branches off into a hose bib valve, then a short washer hose (two female side) into another hose bib, and that then branches off into the heat exchange plate for the heated water that runs into the hot air exchangers, back to the boiler, etc. etc.

Bottom line, I knew that the water in the boiler is "yuck" and the thought of opening both hose bibs at the same time mortifies me. I looked, and from my limited knowledge, I'm 99% sure there is no BFP (backflow preventer). So . . . can you look at this short video, and tell me what you would do to take that ground well water source and get it into the boiler water system for a refill?

CLICK HERE FOR VIDEO
 
First I can't open your video. Post it to you tube then add a link here.

Few thoughts, normally there's an over temp kill switch built into furnaces to prevent runaway situations. I'd check and see if thats working properly.

Second, domestic hot water (I'm pretty sure) should be on its own loop and not routed through the heating water loop. I'm pretty sure thats how my father in laws boiler is set up. So not potable water is ever in the boiler.

I would think filling it would be in the manual for the unit. Normally if you contact the manufacturer they will supply you with the manual, tell you where to download it or just let you know what to do.
 
First I can't open your video. Post it to you tube then add a link here.

Few thoughts, normally there's an over temp kill switch built into furnaces to prevent runaway situations. I'd check and see if thats working properly.

Second, domestic hot water (I'm pretty sure) should be on its own loop and not routed through the heating water loop. I'm pretty sure thats how my father in laws boiler is set up. So not potable water is ever in the boiler.

I would think filling it would be in the manual for the unit. Normally if you contact the manufacturer they will supply you with the manual, tell you where to download it or just let you know what to do.
Thanks for the response. Can you try the link now? It worked if you copy and pasted, but "blocked" if you clicked. But I just changed it to text and attached link, and now it seems to work when you click it.

As for your points:

1. I agree - should be a kill switch, but doesn't seem to be working. I just checked the manual I have, and it suggests there definitely should be a "oven temp safety switch" in the back and inline with the "white" power cable. I'll have to take a look at what's up with that.

2. Yes, I understand this, and in fact I think this is true in my set up; however, there is a connection from domestic water to the heating system water, with shut off valves, likely installed just for the purpose of what I'm asking (to fill up the boiler with water). This seems to be something not necessarily unexpected, as Central Boiler demonstrates here: (however, my setup is not like in the video - no side-arm).

3. The owner's manual I have is among the crappiest, least helpful I've ever seen for a product when it comes to product specs and technical info - there are NONE! I think this boiler was manufactured by a smaller "ma & pa" outfit. Either way, nadda is in the manual I have about filling up - not even specifications as to how much water it can hold. I did talk to the outfit that made it (they still make processing equipment, but not the boilers) and they were unable to point me to any technical specs manual online (I don't think it exists).
 
Kinda hard to follow all the details here, and I don't own an OWB, but it's hard for me to understand how or what hazardous substances would enter or be produced in your boiler.

Yuck factor, to be sure. But hazardous?

What am I missing?
 
First I can't open your video. Post it to you tube then add a link here.

Few thoughts, normally there's an over temp kill switch built into furnaces to prevent runaway situations. I'd check and see if thats working properly.

Second, domestic hot water (I'm pretty sure) should be on its own loop and not routed through the heating water loop. I'm pretty sure thats how my father in laws boiler is set up. So not potable water is ever in the boiler.

I would think filling it would be in the manual for the unit. Normally if you contact the manufacturer they will supply you with the manual, tell you where to download it or just let you know what to do.
That is correct. Potable water should never mix with boiler water. The boiler is a closed loop system. In a sidearm heater exchanger they "touch" but never comingle.
 
That is correct. Potable water should never mix with boiler water. The boiler is a closed loop system. In a sidearm heater exchanger they "touch" but never comingle.
I agree, and I am saying the same thing; however, it's not a side arm installation.

Are you able to see my setup in this video?

CLICK HERE FOR VIDEO
 
Looks like a bypass is installed for the heat exchanger, which is what goes to your hot water heater. Stand back and just take a few pictures of that exchanger, and then the piping at the boiler.
 
Looks like a bypass is installed for the heat exchanger, which is what goes to your hot water heater. Stand back and just take a few pictures of that exchanger, and then the piping at the boiler.
Attached - piping to the boiler runs through the larger blue pex piping into the basement closet, outside wall, then down underground, to the OWB unit (can't get a pic of it at the moment - underground piping and otherwise need to remove back cover by unscrewing several bolts).
 

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bypass for summer use?
One question about your OWB, is it a pressurized system or an open system?
Mine is a Heatmor and is an open system for all practical purposes. You should be able to put a garden hose into the top vent and fill it that way. When I installed mine I added a fill line to the return line so I just crack the cold water valve to add water, I add until it bubbles out the vent. (on the Heatmor there is a weighted ball that sits over the vent in theory making the stove to have 3 psi)

ETA: this site may have some useful information for you https://**************************/forum/index.php
It won't let me cite it because it's a competitive site? PM me if you want it **************************
 
Because this is the kind of stuff that is put in the water tank of an outdoor wood boiler:

https://cdn.altheatsupply.com/media...c015e872a675/p/r/protech300-toprint-final.png
The only hazardous ingredient is sodium nitrite, the same stuff that's used to cure meat. If Wikipedia is right on the toxicity, and I did the math right, you'd have to drink nearly your body weight in boiler water to get a lethal dose. I'm not suggesting not to be concerned, but it seems that adding a back flow preventer or spring check at the hose bibb would be easy to do and more than safe enough.

Me, I'd probably use the setup you have and run the hose bibb for a couple minutes after charging the boiler on the unlikely chance there was any backflow.
 
The only hazardous ingredient is sodium nitrite, the same stuff that's used to cure meat. If Wikipedia is right on the toxicity, and I did the math right, you'd have to drink nearly your body weight in boiler water to get a lethal dose. I'm not suggesting not to be concerned, but it seems that adding a back flow preventer or spring check at the hose bibb would be easy to do and more than safe enough.

Me, I'd probably use the setup you have and run the hose bibb for a couple minutes after charging the boiler on the unlikely chance there was any backflow.
I mean, OK, but the label literally says "may be FATAL if swallowed." I'd prefer to keep it out of the drinking water.

But one thing I was thinking is if I could find a cheap, inline backflow preventer to put on the potable water side and prevent any backflow from the boiler side back into the potable water side.

I'm not having any luck finding one that is small, and the right threading that also DOES NOT have the immediate pressure release like some of the garden hose models I've seen.
 
bypass for summer use?
One question about your OWB, is it a pressurized system or an open system?
Mine is a Heatmor and is an open system for all practical purposes. You should be able to put a garden hose into the top vent and fill it that way. When I installed mine I added a fill line to the return line so I just crack the cold water valve to add water, I add until it bubbles out the vent. (on the Heatmor there is a weighted ball that sits over the vent in theory making the stove to have 3 psi)

ETA: this site may have some useful information for you https://**************************/forum/index.php
It won't let me cite it because it's a competitive site? PM me if you want it **************************
Sent you DM.

It is open - I can take the top off where the water level gauge cap rests.

Here's the boiler I have (discontinued everywhere): http://michiganfirewoodproducts.com/Item/bf-5800

I could dump a garden hose in there, but it's very far away from a water source. I may be able to snake hoses together and have enough, but I'd like to see about my current set up, because I have a very sneaking suspicion that bypass was specifically installed to fill the boiler system from the ground water.

I have to imagine, if nothing else, I could get a backflow preventer to at least ease my mind. Just having trouble finding a good one.
 
Sent you DM.

It is open - I can take the top off where the water level gauge cap rests.

Here's the boiler I have (discontinued everywhere): http://michiganfirewoodproducts.com/Item/bf-5800

I could dump a garden hose in there, but it's very far away from a water source. I may be able to snake hoses together and have enough, but I'd like to see about my current set up, because I have a very sneaking suspicion that bypass was specifically installed to fill the boiler system from the ground water.

I have to imagine, if nothing else, I could get a backflow preventer to at least ease my mind. Just having trouble finding a good one.

Can you attach a pic with the two lines going to and from the OWB marked on the plate HX
 
They probably just added the bypass for summer use so you (they) weren't heating the OWB via the plate heat exchanger.
I'll look at your pics again here after dinner
That is doubtful, because what I haven't disclosed yet is this is on only the ONE heat plate exchanger over the ONE water heater. I have two wall mounted heat plate exchanges each over one of two water heaters. The one you see is for the auxiliary dwelling unit attached to our house, the other is for the main house. There is no bypass over the main one like this one you see in the pictures in the above post. The heat exchange plates are all "daisy" chained to each other, of course, for one continuous system flow. So, if this were used to not heat the exchange plate, it would be needed at both exchange plates attached to both water heaters.
 
I mean, OK, but the label literally says "may be FATAL if swallowed." I'd prefer to keep it out of the drinking water.

But one thing I was thinking is if I could find a cheap, inline backflow preventer to put on the potable water side and prevent any backflow from the boiler side back into the potable water side.

I'm not having any luck finding one that is small, and the right threading that also DOES NOT have the immediate pressure release like some of the garden hose models I've seen.
Plain old water, and plenty of other things we consume every day, may be fatal if you swallow enough. The recommended dilution of the Protech is 300:1 in your boiler. So, yeah, a cup straight out of the jug might kill you.

Personally, I think a backflow preventer is overkill, considering that filling your boiler is not an automatic, unattended operation, like on a normal pressurized boiler. But there a number of choices here, assuming that's 3/4 PEX tubing:
https://www.supplyhouse.com/sh/control/search/~SEARCH_STRING=3/4 inch backflow preventer
Simple 3/4" checks:
https://www.supplyhouse.com/Spring-Loaded-Check-Valves-24911000
 
Plain old water, and plenty of other things we consume every day, may be fatal if you swallow enough. The recommended dilution of the Protech is 300:1 in your boiler. So, yeah, a cup straight out of the jug might kill you.

Personally, I think a backflow preventer is overkill, considering that filling your boiler is not an automatic, unattended operation, like on a normal pressurized boiler. But there a number of choices here, assuming that's 3/4 PEX tubing:
https://www.supplyhouse.com/sh/control/search/~SEARCH_STRING=3/4 inch backflow preventer
Simple 3/4" checks:
https://www.supplyhouse.com/Spring-Loaded-Check-Valves-24911000
Cool thank you! I didn't know what other items existed that do the same thing. The CHECK VALVE might be a good, and cheap option.

THanks!
 
The way you describe your system, your already completely isolated from domestic water and boiler. Thats what the heat exchangers are for.
I can't say what the valves are for, as there isn't enough valves at the right places for a rel bypass. There would need to be one to shut flow off to the heat exchanger on the heat exchanger side of the pex. The only shut off valve I see is after the hose valve, so it would completely stop flow, not bypass. Either way, without any of us being there it looks like you should be fine.
I'd fill as Dave suggests above, just give yourself a little head room so when the water heats back up it doesn't over flow again.
 
The way you describe your system, your already completely isolated from domestic water and boiler. Thats what the heat exchangers are for.
I can't say what the valves are for, as there isn't enough valves at the right places for a rel bypass. There would need to be one to shut flow off to the heat exchanger on the heat exchanger side of the pex. The only shut off valve I see is after the hose valve, so it would completely stop flow, not bypass. Either way, without any of us being there it looks like you should be fine.
I'd fill as Dave suggests above, just give yourself a little head room so when the water heats back up it doesn't over flow again.
Yes, and I apologize if I've been making this unclear.

I am aware that the heat exchangers keep the boiler water separate from the domestic water, but do transfer the heat from the boiler to the water heater.

And you are correct, the one valve you see in line on the domestic supply water in would shut off the flow completely.

However, you see those two hose bibs (yellow valve handles) with the washer hose in-between the two? Open the one on supply side, then open the one on the boiler water side--in theory--should supply domestic ground well water into the boiler system water supply, this filling up the water boiler system with more water.

I'm guessing I would need to turn the pump off at the boiler, and this would eliminate pressure in the boiler water system (it is an open OWB). With no pressure from the boiler water system, I'm no supposing there should be no problem or concern with backflow?

Either way, push comes to shove (and I remain this concerned about it), I may just end up snaking the garden hose together. I just hoped to learn and understand better that "bypass" setup, as I continue to suspect it's there for flushing/filling the boiler water system (and with quite ease of convenience, too).
 
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