I'm not sure what the diff is set at. I know if it shuts off and I add 5 gallons of water from my outside well hand pump..it kicks back on... maybe tomorrow I can time the diff after work..
OWB Heat exchanger issues
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maple1
Minister of Fire
Yes... mine is not connected to my water lines I physically have to add 5 gallons daily due to evaporation
maple1
Minister of Fire
Idk...I don't start a fire till temps get below freezing and stay there to prolong my wood supply so I run the pump every fall to prevent any freezing if temps dip down..for the month or so I let it circulate with no fire I never add water. But once I get a fire going inside I almost have to add 5 gallons every day.
maple1
Minister of Fire
Hoping someone with experience with the same boiler will add some feedback. But I am thinking it should only be necessary to add water maybe once or twice a winter, if at all.
If it is filled to the max when cold, it might burp some out when it gets fully up to temp, from expansion. But I don't think that would be near 5 gallons worth. Can't see evaporation getting rid of that much either. But I could be wrong.
If it is filled to the max when cold, it might burp some out when it gets fully up to temp, from expansion. But I don't think that would be near 5 gallons worth. Can't see evaporation getting rid of that much either. But I could be wrong.
hondaracer2oo4
Feeling the Heat
I ran an h4 before. Your top is leaking around your chimney pipe. It steams off quick. You need to pull outer cover and then water jacket top to reseal. You can call hardy if you need directions on how to do this.
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hondaracer2oo4
Feeling the Heat
Yes please check what the high temp is set to and what the differential is (low set point) and time how long it takes after heating up to the high set point to reach the low set point and fire again please.
High is set at 185... cut in temp on the aqua stat says 170... took 15 mins to drop from high to low setting.
hondaracer2oo4
Feeling the Heat
Ok that is 12,450 btus used in 15 mins or 830 btu per min. Now we need to know how many mins per hour your house heat runs during a given outside temp. Thst will tell us how many btus your house is using per hour depending on temp.
It's 5 degrees I'd say it runs for 12 mins ..off for 3 mins... so it might be off12 mins per hour and run for 48
hondaracer2oo4
Feeling the Heat
830 btu per min x 48 mins per hour = 39,480 btus per hour at 5 degrees outside. That is really high which means your house is either very large or leaks lots of air and has little insulation. I am heating a 220 year old house that is 2800 sqft, decently insulated and air sealed now. At -15 degree temps the other night and running thermostat inside at 68 I was using 22,000 btu per hour for comparison. Looks like you need to do lots of insulating and air sealing unless you want to be loading that boiler every 6 hours.
Im not saying my house couldn't use more insulation.. but in theory... wouldn't the heat also run less if I was getting the proper temps out of my register which should happen if I get the proper pump?
hondaracer2oo4
Feeling the Heat
So your house needs so many BTUs per hour to keep the thermostat at whatever set temp you have depending on outside temp. So when you measured this your house needed 39,500 BTUs per hour to keep the thermostat at the set temp with 5 degrees outside. If your pump moved more GPM to the heat exchanger so that instead of putting out 830 BTU per minute lets saying hypothetically your put out 1000 BTUs per min. That means instead of having to run the forced hot air fan for 44 minutes of the entire hour you would have to run it for 39 minutes. At the end of the hour you still needed the same 39,500 BTUs delivered into the house to meet the thermostat setting. The BTU needs of the house only changes up or down depending on outside temp and thermostat setting. Now the complaint with FHA is that you get cold and hot temps as it heats up quick and then cools down. The way to stop this complaint is to slow down the air so that you provide lower register temps and slower moving air to the space so you never get a hot spike, just even temps all the time. A perfectly set up system would hypothetically run 24/7 on the coldest day of the year and be able to maintain the thermostat temp. Unless you cant meet the thermostat set temp or keep up you are actually running very comfortable. Now with that being said your register temps have to be above body temp( 97 degrees) because below 97 degree register temps actually feel cold moving across the skin. So you need 100 plus register temps to not feel like it is a cold draft. You are simply fighting a losing battle because your heated space is losing the heat so quickly. Time to invest in insulation, windows , doors and air sealing.
TBH currently in the process of building a house... going over kill with spray foam insulation and triple pane windows..so I'm just gonna struggle through one more winter with this one....Im thinking of using my OWB to do infloor heat being that it's going to be a slab house... not to get off topic..but anyone do infloor heat or have any knowledge of how well it would warm a 32'x56'x16' building
hondaracer2oo4
Feeling the Heat
Radiant slab or radiant under floor? Both work well when constructed CORRECTLY. Many people don’t construct them correctly and waste energy and have poor performance.
jebatty
Minister of Fire
NE Ohio, feels like warm winters to me. I have a 32 x 48 x 16 pole building with steel sides and roof, 6" of insulation in the walls, 18"+ insulation in the ceiling, 2" foam under the entire concrete floor with pex on 12" centers, and 2" perimeter foam down 4'. My Tarm gasification boiler is in the building, along with a 1000 gal hot water storage tank. Normal winter temps Dec-Feb often -5 to +15F; periods of cold into the -30'sF and lower with daytime highs of -10F can occur in Dec-Mar.
I set the in-floor at a constant temp of 61 to 64F, depending on outside temp. Burn at most once every other day during the coldest periods, more time between burns during warmer periods. Boiler wood is pine and aspen, well seasoned over two summers. 4 cords in cold winters and less in warmer winters cover the heating season.
I set the in-floor at a constant temp of 61 to 64F, depending on outside temp. Burn at most once every other day during the coldest periods, more time between burns during warmer periods. Boiler wood is pine and aspen, well seasoned over two summers. 4 cords in cold winters and less in warmer winters cover the heating season.
jebatty
Minister of Fire
Pex in-floor flow is about 34,000 btuh: 2.25gpm x 500 x 30. That's mixed down hot supply at 100F and return about 70F.
Slab under concrete. I'm also NE ohio.. burning 4 cords a season sounds phenomenal!! I'm looking to do a similar setup but 18" of ceiling insulation.. that's a lot! Lol... I was on a demo job at a giant eagle and Took home a 25'x25'x10' walk-in cooler... was going to use the disassembled freezer panels to insulate my floor... they're 4.5" thick
hondaracer2oo4
Feeling the Heat
You are going to need a gasser and pressurized storage if you want to burn 4cord a year. Jebatty would probably burn 10 cords if it was with your hardy h2.
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Sorry I'm not familiar w the gasser pressure storage...I'm on pace to burn 12 cords in my drafty uninsulated house but I prob start a month later and end a month earlier than most.i use the fuel furnace once the temps are above freezing and stay
hondaracer2oo4
Feeling the Heat
The majority of the guys around here are operating wood gassificAtion boilers with 500-1000 gallons of storage. Many batch burn by firing there boiler once per day to charge the water storage with 180'degree water and then utilize that hot water for 12-24 hours. Many boilers are very sophisticated with computer controls and sensors.
I personally run a outdoor gasser with only 200 gallons of on board storage. I burn 6 3/4 cords a year. The old conventional wood boiler design like you have is very antiquated and basic. While simple in design they are very inefficient. Just the nature of the product.
I personally run a outdoor gasser with only 200 gallons of on board storage. I burn 6 3/4 cords a year. The old conventional wood boiler design like you have is very antiquated and basic. While simple in design they are very inefficient. Just the nature of the product.
Well Maybe w a new house I may need to look into a new system... preferably one I wouldn't have to have a backup furnace for, if that exists
hondaracer2oo4
Feeling the Heat
If you are building a house and had money to spend on a heating system then yes in would look into putting together a high efficiency system ( not a conventional style owb) some type of gasser whether it be indoor gasser with storage or a outside gasser. You will need some type of back up heating system, insurance company won't insure you otherwise. The new house doesn't have natural gas Available to it does it?
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