Electronics problems with Woodmaster Flex Fuel

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JWHIII

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Oct 25, 2012
8
I have a Flex Fuel 60 that I installed fall of 2012. It has worked beautifully on both wood and pellets supplying heat and DHW for 5K sq ft house and shop. The unit quit working last week and at first inspection I believed the lambda (oxygen) sensor had failed. Once I had a chance to remove the sensor and do some testing, I have found that the sensor is working as designed, the boiler control is not supplying power to the o2 sensor heater circuit. Has anyone had problems with the control board on their Flex Fuel?
 
I have a relay and regulated power supply running the O2 sensor heater and the stove operates. I have contacted Woodmaster and am awaiting reply.
 
JW
Just curious what power supply your sensor heater requires, my bosch lsm11 requires 12vac, 16w/1.25amp. Is the relay to turn the heater
 
TCaldwell
The Flex Fuel also uses a Bosch lsm11 which wants 12-14 volts AC or DC. Since there is no output from the control for the heater, I am using a relay that has its coil connected to the 120VAC supply to the primary air control solenoids and contacts hooked to a 12VDC power supply and the O2 heater. The primary air control solenoid was as close as I could get to turning on and off the heater at the proper time without to much hassle. The boiler is operating on auto again while I wait for a reply from WoodMaster.
 
You diagnosed the problem for them, the least would be for them to send a new board or controller. Ask them what their plan is when the lsm 11 is discontinued, as bosch doesn't have a direct replacement in the works.
 
That issue is waaaay too important. Call woodmaster, ask for Warren. He's a tech guy over there. He helped make my installation a breeze.
GS7,
Warren is who I have contacted by email, he had a couple questions and I replied, now waiting again. I am involved in other more important projects at the moment and haven't had the time to call and pester them yet, but I will when I get a free moment.
 
GS7,
Warren is who I have contacted by email, he had a couple questions and I replied, now waiting again. I am involved in other more important projects at the moment and haven't had the time to call and pester them yet, but I will when I get a free moment.
Has wood master gotten you taken care of? I am considering a flex fuel now. It would be nice to see they have good customer service/support.
 
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Any question or concern I ever had was addressed clear and quick...but I've always called unless a photo was needed on their end then I'd email and still call, too important to wait to hear back in my opinion.
 
Any question or concern I ever had was addressed clear and quick...but I've always called unless a photo was needed on their end then I'd email and still call, too important to wait to hear back in my opinion.
GS7,
Do you have a WoodMaster? What is your setup like? Flexfuel? Can I get away with no water storage and modulating it?
 
No Woodmaster doesn't seem to care that I have a problem. Warren ended contact when it became apparent that the control board is bad, I doubt they will warranty it! Also I have been out of town for work, I will be calling them in a few days.

NE Poultry Supply, if you ran it on pellets alone you might be able to get away with it, but you should have at least a couple hundred gallons of buffer storage.
 
GS7,
Do you have a WoodMaster? What is your setup like? Flexfuel? Can I get away with no water storage and modulating it?

I have the Flex Fuel kw30 with 880 gallons of water storage in a forced air set up. Storage is mandatory to correctly set up the Flex Fuel. Minimum storage for the kw30 is about 165 gallons on pellets only and wood 300 gallons minimum. For the flex fuel kw60 minimum water storage is about 285 gallons on pellets only and 300 gallons minimum on wood.
 
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Maybe if service is not so good I should consider the Froling 40/50? I will start a post with that topic.

The warranty is in writing and cut and dry. 10 years on the firebox and water jacket, 1 year warranty on electrical components . Just google Woodmaster Flex Fuel manual, and you'll see the whole manual in a pdf file. It was the first thing I did during my looooong research phase.
 
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I have the Flex Fuel kw30 with 880 gallons of water storage in a forced air set up. Storage is mandatory to correctly set up the Flex Fuel. Minimum storage for the kw30 is about 165 gallons on pellets only and wood 300 gallons minimum. For the flex fuel kw60 minimum water storage is about 285 gallons on pellets only and 300 gallons minimum on wood.
what would happen if you start the fire and your storage is to temp? Smolder go out? do you ever keep the fire going or is it always needing relight every load?
 
what would happen if you start the fire and your storage is to temp? Smolder go out? do you ever keep the fire going or is it always needing relight every load?

If I started a fire when storage was "already up to temp" the sensor would put the machine in a partial burn mode, which is a slower burn. I'd never do that though. It's not advised. The screen on the machine will say the tanks are fully charged are you sure you want to add more? So I don't unless needed. Once you get a feel for how many hours you can heat, I then load the cold firebox while the tanks are charged to temperature, and when there is a need for heat my auto lighter then and only then automatically starts a new fire. No waking up at night, no freezing morning greetings. No smoldering fires for me. The thing is having your unit sized for the space and with the proper amount of storage. You really want a healthy all out burn which is a 4 hour burn for my unit. Last winter (my first winter), in my case meant anywhere from 1-3 fires in a 24 hour period. (2 was my average). That's heat and hot water 2700SF 1973 2 story colonial with no updated insulation and single pane windows. The 3 fire days were only on the coldest of days. It was no surprise. It was calculated before I bought and I was told the kw60 would mean less firing, but since I'm around I went with the kw30. Only ran pellets for 4 days to try it out. Was great, but I had free wood and pellet prices are not that great to me.
 
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If I started a fire when storage was "already up to temp" the sensor would put the machine in a partial burn mode, which is a slower burn. I'd never do that though. It's not advised. The screen on the machine will say the tanks are fully charged are you sure you want to add more? So I don't unless needed. Once you get a feel for how many hours you can heat, I then load the cold firebox while the tanks are charged to temperature, and when there is a need for heat my auto lighter then and only then automatically starts a new fire. No waking up at night, no freezing morning greetings. No smoldering fires for me. The thing is having your unit sized for the space and with the proper amount of storage. You really want a healthy all out burn which is a 4 hour burn for my unit. Last winter (my first winter), in my case meant anywhere from 1-3 fires in a 24 hour period. (2 was my average). That's heat and hot water 2700SF 1973 2 story colonial with no updated insulation and single pane windows. The 3 fire days were only on the coldest of days. It was no surprise. It was calculated before I bought and I was told the kw60 would mean less firing, but since I'm around I went with the kw30. Only ran pellets for 4 days to try it out. Was great, but I had free wood and pellet prices are not that great to me.
Great info. Thank you.
That auto ingnite sounds incredible... This is the only system that I know of that has it... I would like it.

How is cleaning? The Tarm Froiling has the leaver on the outside to clean the tubes. That seems like a plus. I cant find video or docs on cleaning the Flex Fuel. The pellet option is good because it gets me a $5k rebate but it costs 3k to get it. I think I would burn wood mostly too, just cause it is cheaper for me.
 
Great info. Thank you.
That auto ingnite sounds incredible... This is the only system that I know of that has it... I would like it.

How is cleaning? The Tarm Froiling has the leaver on the outside to clean the tubes. That seems like a plus. I cant find video or docs on cleaning the Flex Fuel. The pellet option is good because it gets me a $5k rebate but it costs 3k to get it. I think I would burn wood mostly too, just cause it is cheaper for me.

The Flex Fuel cleans itself automatically after each fire. After 4000 or 6000 hours you clean the turbulators that handle auto cleaning. Other than that clean your chimney of fine ash aa you normally would during or at the end of the season as needed.
 
The Flex Fuel cleans itself automatically after each fire. After 4000 or 6000 hours you clean the turbulators that handle auto cleaning. Other than that clean your chimney of fine ash aa you normally would during or at the end of the season as needed.
Great info. Thank you.
That auto ingnite sounds incredible... This is the only system that I know of that has it... I would like it.

How is cleaning? The Tarm Froiling has the leaver on the outside to clean the tubes. That seems like a plus. I cant find video or docs on cleaning the Flex Fuel. The pellet option is good because it gets me a $5k rebate but it costs 3k to get it. I think I would burn wood mostly too, just cause it is cheaper for me.

Not surprising about the lack of info. I contacted Solar Focus in Austria before I bought. Woodmaster is like a mechanic with a Lamborghini and tells a few people by word of mouth. At least that's what it feels like to me. Under marketed/promoted?
 
How many cords did you go through?

Approximately 4 cords from end of December to early April. It was a self installation so it took time. No dealers/installers in my area. After all my hard work oil hits a low lol. Still very happy. Even happier after watching a neighbor just switch to propane.
 
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