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[wrudoing]

Well I have a 1 year old 6048 that heats my shop and i am in the process of installing another 6048 at my house they are the same furnace right down to color execpt the new one now has to have a thermostatic valve installed in each line set? The dealer says CB has found out that water temps below 150 tend to condinsate more causing corrosion so the valve has to be installed to recirculate the water back to the furnace to mantain the 150 water in the boiler or the corrosion portion of the warranty will not be covered.  So if i understand this right anything less than 150 water and the exchanger will be by passed and you have a cold house!!!!!  Any comments/thoughts on this

[Ridgekid]

I have that thermo valve too. I also think this is why they have a operating setpoint of 185F. Thats to prevent cresotoe build-up.

Just my .02

[Scott7m]

I have that thermo valve too. I also think this is why they have a operating setpoint of 185F. Thats to prevent cresotoe build-up.

Just my .02

How does it affect your creosote?  You ever ran yours at 185 vs 160? 

Also, the key thing in preventing creosote is properly seasoned wood. 

On another note, creosote in an OWB isn't really a big deal.  Indoors it can cause a chimney fire but outside a good chimney fire isn't a bad thing lol

[wrudoing]

Dealer said it's to help eliminate moisture which helps with corrosion. My question is the 6048 i have now does not have the valves and i come into work with 95 degree water but still have a warm shop. Does anyone have trouble keeping the house warm with the water recirculating in cold weather?

[Ridgekid]

Scott-

At 185F I would have hotter burns. And agreed-seasoned wood is a key to operating a OWB.

Back in April when I was getting 30F+ nights and 60F days I turned up the thermostat to take the chill off. It would take two burns (Approximately 10 minutes each) to get the house warmed up. (From 72-78F)*  Wood consumed? 8 pieces-split, 24" long in a 24 hour period. Three pieces would still be visuable before the next restocking which was done in the evening before sundown. 

Now- Lets talk burn times. No matter what size unit you have it's going to operate differently depending on the thermo load you put on it. (I think we can agree on this). A small OWB and large thermo load is going to eat wood like theres no tomorow. A large wood burner and small thermoload is not going to operate as much and probably creosote up pretty fast. My point is-properly size your unit and you can probably run it at whatever temp you want. It's your stove. Expieriment with it.

*=My office was in the basement then, now that we are empty nesters I took one of the upstairs bedrooms, so I won't have to crank it up so much next winter.

[Scott7m]

Well...   I do wanna argue a little bit haha surprise surprise

ok....  Let's say your water is 170, it needs to raise to 180 to kick off.

Your draft has just opened, how does the firewood/fuel your burning know what the temperature of the water is around it? 

Now from my experience one thing that I have seen make a hotter burn because of the amount of time it ran was having a bigger swing in temperature.  Let's say if you have a 5 degree swing and it takes ur stove 8 minutes to recover, let's now say you have a 20 degree swing and it takes ur stove 25 minutes to recover,  the longer burn from what I've seen can actually have higher firebox temps and burn off more creosote. 

I have stood outside with a temp gun on the door of my stove comparing how different intervals change the temp, and longer runs equal hotter temps on the box.  Now as far as your water temperature causing an increase in fire temp, I don't get that.

A btu is a btu, it's the amount of energy it takes to raise a pound of water 1 degree

[Scott7m]

As far as burn times, well there are so many variables I can't even begin to make a comparable.

In weather like you mentioned.  My ncb175 heating 2300 sq ft and hot water for 4 would need checked once per day. In weather like that I like to burn junk wood, a 12-14" round of pine 26-28" long would probably about cover that day, i would throw in probably 2 split pieces of oak to make sure.

But all that is just something u have to play with... 

Experiment 4 of last winter was oak cut 2 months prior vs oak cut over a year ago.  Over the course of several runs in average winter conditions of 15 at night and 30 in the day I could easily get 16 hour burns on 2/3 load of oak that was seasoned.  On a night which was nearly identical I'd use green
would and record my results, the green wood would be gone after 11-12 hours and my stove would be probably down to 115 or so, where as after 16 hours with my seasoned wood the temp would still be 158 and have descent coals left.  So if I waited til the seasoned load cooled to 115 you might as well say that seasoned wood was nearly twice as efficient.

Another experiment was coal, 20-30 pound of coal mixed with seasoned hardwoods would give me a 20-24 hour burn in 0 temps at night.   

[Ridgekid]

Is this a trick question?  "Your draft has just opened, how does the firewood/fuel your burning know what the temperature of the water is around it? " Isn't that why the controller is monitoring the water temp? Or am I missing your point?
 
As you may already know the CB controllers have a 10F differance between on/off. For example- The operating range is 190-165F for the off setting. ON will be 10F below what ever setting you choose. Because of the mandatory thermostatic valve (part of warranty and has a preset of 150F) ) it will not go lower than that.

Getting back to my burn time-The example I set above is from the one full week I ran the CB. Thats it! It's new and this upcoming winter I should have a better idea about what my burn times will be. All I can tell you is that I have 74 sq ft firebox and have not loaded it over 1/2 full. Those eight pieces I loaded were like a pyramid in front of the damper.

Argue? No not me. You obviously have more expierance in OWB's than I do. I am a newbie! I hope our public discussions are informative to our readers! 

[Scott7m]

Not a trick question at all.  Yes I'm sure it's informative.  My point is you think you have a hotter "fire" because ur water is warmer at 185.  My only point is that the firebox/fuel inside is just setting there, and it will only burn when it's provided the o2.  Soo at a 10 degree swing like you mentioned I'm saying it takes the same amount of heat to raise water 10 degrees whether it's 160 or 180.  From what I've experienced in that is the only way you'll raise internal firebox temps is by having a longer burn of let's say 20 degree swing vs 10. 

But maybe I'm misunderstanding what your saying. 

[Ridgekid]

I think we are saying the same thing but a little different. As already mentioned, A btu is a btu, it's the amount of energy it takes to raise a pound of water 1 degree.

I was just relaying the info in the owners manual that 185F operating temp is recommended because of the thermostatic valve and "to prevent sweating" of the firebox.

I know nothing of the operation of a heatmaster.

Regards~

[wrudoing]

Guys Guys the thermostatic valve should be mounted indoors and controls the flow of water either to the exchanger or back to the furnace.  I think this is new this year and the question can't be answered yet. But here it is again how many times are you going to burn down past 150 and wake up to a cold house because the water is cold (less than 150) and the valve will send it back to furnace not letting it go thru the exchanger therefore no water no heat.  I know all about burn times,  lets say my schedule gets messed up. and can't fill when i need to,  my shop 6048 would burn down to say 90 but my exchangers will still be pulling heat from that 90 water which means i still have a warm shop at least for while,  i know depending on outside temps and wind conditions ect......  The new valve won't allow any water colder than 150 thru to the exchanger. All I'm saying you and I will have to keep a much closer eye on water temp and fill ups which i believe is going to be a pain    They have taken alot of the flexability away  Does anyone understand what I'm saying?

[Scott7m]

Guys Guys the thermostatic valve should be mounted indoors and controls the flow of water either to the exchanger or back to the furnace.  I think this is new this year and the question can't be answered yet. But here it is again how many times are you going to burn down past 150 and wake up to a cold house because the water is cold (less than 150) and the valve will send it back to furnace not letting it go thru the exchanger therefore no water no heat.  I know all about burn times,  lets say my schedule gets messed up. and can't fill when i need to,  my shop 6048 would burn down to say 90 but my exchangers will still be pulling heat from that 90 water which means i still have a warm shop at least for while,  i know depending on outside temps and wind conditions ect......  The new valve won't allow any water colder than 150 thru to the exchanger. All I'm saying you and I will have to keep a much closer eye on water temp and fill ups which i believe is going to be a pain    They have taken alot of the flexability away  Does anyone understand what I'm saying?

I understand 110%.......   On days when I had to work late or something and came in after 20 hours and my stove was down to 90 degrees or less, my house was still warm!  My stove water was cool but my children were WARM! 

Thats whats important to me, the whole thermostatic valve deal I can see how it works, but it looks like its a lot less user friendly and such. 

[Ridgekid]

Could it also be a "Freeze protector"? CB wants you to install it in the house. Having the thermostatic vavle close at 150F, you could maintain heat longer in the stove, just in case you forgot to restock it? We all have back-up heat right?

Just a thought..... although my brain cells are wearing a little thin on the subject.

[Scott7m]

Could it also be a "Freeze protector"? CB wants you to install it in the house. Having the thermostatic vavle close at 150F, you could maintain heat longer in the stove, just in case you forgot to restock it? We all have back-up heat right?

Just a thought..... although my brain cells are wearing a little thin on the subject.

I understand that being in the house.  However I'm just not sure of the risk vs reward of the whole idea.  I always tell customers that they should always have a backup heating source but they don't always listen.  I know several folks who have OWB as there stand alone heat source.  I understand that though because if you give 8000 dollars for something to heat your home you dont want to also pay 5-7K for a good heat pump to "back it up"

[wrudoing]

Having a backup is not the problem the idea of using it is though. There idea is not freeze protection,  because of the constant circulation,  it would have to mighty cold and burnt out for awhile to be of concern. It's for corrosion due to moisture but i think it's going to be pain keeping the temps up we'll see.

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