Wood fire boiler power outage

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Tswami

New Member
Feb 11, 2014
4
Roanoke, VA
Hello,

We are staring down a big snow starting tomorrow and I have a question about using my boiler with the power out.

I have a 2200 sf 2 story house, 4 zones, burnham wood fire boiler with 2 circulator pumps. housed in my garage attached to the house. I believe closed loop. Well water. I can give me info if needed.

My question is on the front of my boiler it says I can operate the boiler without power by using it as a gravity feed system by opening all of the reliefs. Thats all it says and I'm not really sure what that means. It was in the house when we bought it and I'm still learning. It is the only heat source but does have an electrical backup that uses heating coils like a hot water heater. In the event of a power outage I couldnt use those because they would pull too much for my generator and I can't figure out how to run just my pumps with the generator so I can use wood. Is there a way to run the system without power? I searched and read about a battery backup but I'm in a pinch with the weather coming tomorrow. Should have prepared sooner.

Thanks in advance. This is the only picture I have of my boiler at the moment. that door goes directly into the house
 

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Try it with a small fire before you loose power. Is your generator large enough to run the whole house? If so you don't need to do anything except to remove power from the resistance heaters and your generator should run the boiler if it is tied in to the electrical panel. If you need to hook the generator up specifically to the boiler then the best way is to wire it in to your emergency disconnect switch (the one with the red cover). If you're not comfortable or lack knowledge of residential power disregard the suggestion and get yourself an electrician ASAP.
 
I don't know much about your boiler, but if your boiler were in the basement and all zones located above it you could open all the zones and it would gravity feed I would think. But yours is in your garage and it looks like the same level as the house. Are the zones located above boiler? I know I have operated many oil/gas boilers this way when a pump has failed. With wood I would keep close attention to water temps and use small loads of wood till your sure it is working.

I can't see why you can't find the circuit for the boiler and somehow temp. wire the boiler and pumps and 24 volt transformer for the thermostats and zone valves.
Battery back-up is great but you still would have to wire it in. I have my boiler, pumps, 24 source all wired to a corded plug that I can simply unplug and
plug into my generator or a backup battery source.

By the way I am looking at the same potential crap as you are, Good Luck! Post back with some more details about the wiring of the boiler, it should be
fairly easy and is not a big electrical draw.
 
Generator is a honda 7500 so its got enough power to run most things. Probably wouldn't run anything other than the pumps for the boiler, fridge, freezer and a couple lights. Maybe the well pump if needed. My system is closed so I wouldnt need more water for it.

My boiler is on the ground level with two zones above it and 2 on par with it. I may try and wire in a temporary switch just to get me through. I'm not so concerned with heating my house as much as I am not letting the pipes freeze. If one of them busts thats a whole lot of water pouring into my house.

There is a breaker on the main panel that powers the pumps and the electrical heat, the power splits and runs down to the pump and into the heater which has a breaker to turn the heat panel on and 4 breakers one for each element. During normal power the switch on at the panel keeps the pumps running and I can turn the electrical heat on and off by the breakers. I just turn them off and leave the pumps going and heat with a fire. My concern with it set up like this is that I dont know if I can isolate the pump from the electrical heat to wire a temporary switch.

I do not want to turn this into an arguement about backfeeding but thats a possibility too. I have consulted with a certified electrician to understand the risk and requirements invloved. Hopefully it doesn't come to that but if its between the pipes freezing and that I may risk it.

I live on the side of a mountain in SW Virginia at about 1700 ft elevation so I always end up getting the worst of the snow. I'm from NC originally and my family is all there in Winston salem. Looks like you guys will get a bit, should be interesting. At least we are semi prepared up here.
 
The idea is to manually open your zone valves so the heat will go up into your zones naturally by convection - then return down the other side to the bottom of the boiler as it cools. This can work very well - but the UP part needs to be right above your boiler. If there is much OVER before it goes UP, that will hinder flow. By the sounds of it, your zones go OVER into your house, then UP into it? I suspect that won't flow very well - it may have flowed good when the boiler was in the house. You can test that very easily - just manually open your zone valves & see what happens. Shut the power off to the boiler first, but be sure you don't have a big fire on - it could also overheat pretty quick if it doesn't shut the air off to the fire good and you don't get good flow going.

But - a no-power dump zone arrangement should be part of a normal boiler setup - so what happens when the power goes out & there is a fire burning? Was that accounted for in the move of the boiler to the garage? When the power goes out, there should be a Normally Open zone valve in the system that automatically opens and lets the heat start to flow by convection.

One could rig up a simple no-power solution quite easily for a generator to get pumps going - like somewhere in the power feed to the pumps, before the pumps, disconnect the wires from the pump, wire those into a new receptacle, then wire a cord & plug onto your pump and plug that into the receptacle. When the power goes out, unplug the pump & plug it into an extension cord plugged into a genny. You also want to watch the fire very close as you'll likely be controlling it manually, and manually open the zone valves as required. Or you could perhaps even wire in the receptacle/plug closer to the breaker to get more things working off the plug - I make no claims that any of that stuff is up to electrical codes though.
 
The guy that built the house built the boiler in the garage so it has always been in there. If you look at the picture on the wall you can see just part of the knobs to the zones they go straight up but go into the ceiling and walls so I have no idea which direction they go after that. I am cautious enough with the fire to not let it keep going without pumping. When I first moved in I woke up a couple nights to what sounded like a train roaring in the garage and the pipes howling. Didn't take long to learn from those mistakes.

I'll take a look at the wiring and see what I can come up with. I'll see if I can get some pictures and more info posted up
 
Your generator is 7500 watts...........

It'll run your house w/o any problems. As long as you don't use any type of electric heat, ie. dryer, range etc. Even then you could run a dryer or electric range with 7500 watts. Just be a watt-miser and don't turn lots of things on all at once, but a 7500 watt generator is more than enough to run an entire house.

TS
 
We used to be able to get a deal that went In between the electrical meter socket and the electrical meter. Came with a cord. As soon as you plugged the cord into the meter it opened the incoming as to make sure of zero chance of backfeed while it connected to load side. Just plug into generator and away you go. Only turn on the breakers you need. I think they came in 30 and 50 amp and were around 100$.
 
The guy that built the house built the boiler in the garage so it has always been in there. If you look at the picture on the wall you can see just part of the knobs to the zones they go straight up but go into the ceiling and walls so I have no idea which direction they go after that. I am cautious enough with the fire to not let it keep going without pumping. When I first moved in I woke up a couple nights to what sounded like a train roaring in the garage and the pipes howling. Didn't take long to learn from those mistakes.

I'll take a look at the wiring and see what I can come up with. I'll see if I can get some pictures and more info posted up

Sorry - took 'It was in the house when we bought it' to mean we later moved it to the garage.

Train roaring & pipes howling sounds suspicious - if you haven't before I think I would test out it's dumping capabilities.
 
Get a standby generator like a Generac or Kohler. Less than $3K for an 8kw, including installation and the transfer box. I put one in 2 years ago and now no worries. Will run virtually everything .

Pat
 
A permenant NG or propane generator is in our future because of the place we are. Up on the side of a mountain means we are last to get power. It was 9 days this past summer during a big storm. Unfortunately its supposed to start in 3 hours so that won't do me much good in the short term.

I looked at those transfer switches for the generators and that would be nice but there wasnt anyone in the area available yesterday or today to come up and do anything because they were booked solid because of the snow coming. Thats what I get for waiting.

In the meantime I can backfeed and run the circluator pumps fridge freezer well pump and be just like normal. I dont have another AC/heating unit so no big power drains and I wouldnt be washing clothes or cooking on the stove. I have a wood fired stove outside and a grill. That should get me through.

I did look at the power coming off of the circulator pumps and it would be relatively easy to wire in a backup plug on them if needed as well but I'll have to make that call later.

The pipes howling and clanking happened when I got the water wayy too hot one time like 210 or so. I think I got some air in the lines and everything boiled off and it was just pushing steam around. That was no fun.

Below is the statement I was asking about posted on the front of the boiler.
 

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So - sometime when you have a low heat demand, and your zones aren't calling, and the boiler is hot but with not much fire in it, and you've got some time - just cut the power to the entire heating system and see what happens. Some heat should gradually flow into at least one of your zones, if there is a properly wired & installed & working dump zone. Then after a while & seeing what happens, manually open all of your zone valves & then see what happens. Heat should slowly move into all of your zones then. After a short time the boiler should start to cool off, as return from the zones makes its way into the bottom of the boiler. Then you can feed the fire a bit - you should have to manually open a draft control or the draft a bit for it to burn, since the power loss should have closed your draft damper. You will need to keep a close eye on your boiler temps. This should all be done over the course of a couple of hours, to get a firm grasp on how it will work or how capable it will be in a power outage - better under your terms rather than in an emergency situation when you truly have no power and temps get to dropping.

Also agreed that your genny has waaay more than enough ooomph to run your system. After monitoring our usage here for the past month or so, I have concluded that our house can run just fine for days on end in a no-power situation with just a 3kw generator, and if it was an inverter would be running at half-load & speed for 90% of the time. Which is a pretty big factor for us as we don't have NG or propane and would have to rely on jugging lots of gas from the closest gas station which is 15 minutes away.

Likely goes without saying but just be very careful with any backfeeding - we all know what can be said about that, but I also understand about being in dire straits. I have come full circle in my thinking from running extension cords, to doing a whole house thing with transfer box or generlink, now back to small generator & extension cords again - we just don't seem to have the outages here we used to have (knock on wood very loudly...). I think I would do the Generlink setup and a 7kw diesel generator if I had to have something bigger and we were still having numerous extended outages.
 
I haven't read everything above but I'm assuming that when you say backfeeding you are using a suicide cable. Be careful and be sure to shut off the main breaker to keep from frying the line worker. If you're backfeeding on only one leg it has to be on the same buss as the boiler breakers. If you're plugging into both legs (220) you will power up both legs.

Maple, I know many people have diesel and gasoline portable generators for back-up but the problem arises when they don't get used enough and the fuel goes bad. In an oil boiler bad fuel will work albeit poorly but with a carburetor or injectors bad fuel can really foul things up. my gas generators worked fine for me when I was building and using them regularly but when I retired they just sat there waiting for a power outage and things got gummy.
 
I think I would do the Generlink setup and a 7kw diesel generator if I had to have something bigger and we were still having numerous extended outages.
Gasp..... you mean you would have diesel fuel, aka home heating oil again..........I thought better of you LOL.

We all know oil has it's place, and it's for RUNNING STUFF! Not heating long term.

TS
 
Gasp..... you mean you would have diesel fuel, aka home heating oil again..........I thought better of you LOL.

We all know oil has it's place, and it's for RUNNING STUFF! Not heating long term.

TS
We've got a tank here that usually has diesel in it - gotta feed the tractors.
 
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