Print

[victor6deep]

Really starting to wonder if this rusting out if lower temps are used is true or a bunch of BS. How in the world does a firebox rust if proper boiler treatment levels are used in the water jacket? Im sure lots of people run less than 180 HI and have had a stove for 20 plus years. My stove manufacture manual told me to run 165 with a 15 degree diff and now they just sent out a notice advising 180 with a 15 to 20 diff. I am just very skeptic about the whole rusting out thing at lower temps. If a owner burned straight greenwood at 140 Hi and didn't use any boiler treatment nor does he change his water I could see it but for the guy using proper treatment and using decent wood staying at 160 or 170 HI I just don't see it happening. Thxs

[Scott7m]

is this serious?  Why do all boilers have primary and secondary loops? 

It has nothing to do with water treatment,nothing at all.  It's the water that's "inside" the firebox gathering on the walls, and condensation running into the ashes.  It has nothing at all to do with water treatment or anything like that.

Most small boiler manufacturers knowledge about hydronic heating to about as far as being able to weld.

Why would central and empyre and other companies who are now starting to require boiler protection do this?  It sure isn't to make more money, because it raises the bottom line of the stove and makes it harder to compete, because so many people shop by price alone even when looking a phase 2 products. 

Anyone that's ever built there first fire in the firebox knows what condensation were talking about, when u have a hot fire surrounded by water cooler than 140 you'll literally see water running down the walls.

I see this about 40 times a year doing installs, every customer freaks and thinks they have a leak, temps get over 140ish, that stops, things dry out.

I was asking if u were serious though because we've discusses this at length in pm's and on the forum, and somehow u were still thinking it had something to do with boiler treatment? 

However yes there are likely many stoves running near 20 years old that run less than 180, but if we can get folks to run return temps proper and the stove at proper temps, the average life of a boiler 12-14 years could be extended to 20-22 perhaps??? 

[victor6deep]

Maybe its because I know soooooo many people running 150-160 without any problems for close to 10 years.  If I only paid 3500 for a stove and got 10 years out of it I would be very happy and just buy another. Scott, I know you are very smart with this stuff but I just can't seem to get over the facts.

[yoderheating]

I don't completely buy into it although in some cases I'm sure it has some merit. I've sold and installed hundreds of furnaces and never set the top temp above 170 and have NEVER had a furnace I sold have a corrosion leak. In my opinion the furnaces with ash pans especially shouldn't worry about this because any condensation in the furnace will either evaporate of run into the ash pan. I'm not saying it is complete bs but I believe there are a number of much easier other ways to damage a furnace. I often run my personal furnace 155 with a 7 degree differential and my ashes are powder dry and I never see condensation in my firebox.

[oldchenowth]

I have to side up with Scott on this one.  To me, if nothing else, it takes out moisture in less than ideal situations.  We all do not burn optimum moisture wood that has been covered for two years. I tend to believe that higher temps get rid of water and lessen creosote that can trap water, hence, corrosion.  Just one of those things I don't have a full grasp on, but still figure it does more good than harm.  I always thought running my pump slower would give me better heat, not so.  It actually gave worse results, cranked the pump up on high and more heat with better efficiency.  Go figure. I leave mine at 185 high and get better results all the way around.  The factory told me the harder I work mine the better it will perform.  True.

And with a wood doctor, if you have followed any of the threads, a truth may be a hard thing to come by without valid proof.  I am pretty sceptical myself, victor6, but I think higher temps treat the inside if the burn chamber and treatments help the outside.  Just my opinion.

[Scott7m]

Yea to me it's not even a matter of if or maybe. It's simple science, I never bought into it fully either until I saw first hand what could happen and how it affected the stove. 

Yoder, if your at 155 and your delta is 15 degrees your likely fine, the magic number is actually 136, but we just say 140. 

Once again it's simple science that moisture can and will gather on steel that's cooler than 136, all fuels whether its wood or gas have moisture in them, boilers for over 70-80 years have had primary and secondary loops to prevent return temps from coming back to cold and damaging the boiler. 

Then again, look at the ones in the top of our industry, if you buy a central boiler and don't install the thermostatic valve, "that comes with the stove", your warranty is void!

Same way with empyre on all there gasification units so far, if you buy an empyre and don't install the optimizer thermostatic valve, your warranty is void on day 1

Other companies are also getting ready to start this. 

I had one customer who bought an optimizer from me simply to try it, gasser by the way, stove started staying cleaner inside, cleaning became less frequent, efficienywent up slightly. 

However he did have a large heat load and return temps were always coming back 110-120, now there always coming back above 140 and things are working better, the heating appliances in the home run a few minutes longer each cycle, but his 15k dollar investment is working better and cleaner, that's what ya want

[Scott7m]

Yoder, I'm sure you as well as me have had folks call with water in the ash pans, almost everytime it was folks running them cold, or at 155-160 with wet wood.  Imagine if that was in the bottom of a stove with no ash pan and in the ash bed, big problems.  Maybe that's why Heatmaster as well as others only warranty ash pans for a year and sometimes up to 5 years, perhaps because its a corrosive environment I'm not sure, can't even remember off the top of my head if Heatmaster ash pan warranty is

[yoderheating]

 I've had at least one customer who was running his furnace at 185 and still had lots of water in the ash pan. Running up the temps help a little but if you are burning green birch or white pine you will have moisture no matter what temp you run the furnace. In my opinion the wood quality will have a much larger impact than any temp you may run. As I said before, running high temps may help a little but there are a number of other things that you can do that will have a much larger impact on the life of a furnace. Now on furnaces without ash pans or mild steel furnaces we are talking about a completely different ball game. In those cases, especially with mild steel furnaces, I wouldn't burn green wood at all.   

[victor6deep]

I think the longer differential is harder on the steel also. 15 degree and more just allows the moisture to soak in versus a 10 degree since the stove will run more often which decreases the moisture.

[12valve]

So what's to hot?  why not go 185 to 205?

[bajonesy77]

I think the longer differential is harder on the steel also. 15 degree and more just allows the moisture to soak in versus a 10 degree since the stove will run more often which decreases the moisture.

The moisture that forms inside the firebox is coming from the moisture in the wood, so the less moisture in the wood the less that can collect on the sides. So after the first or second burn cycle depending on amount of wood most if not all moisture should be cooked out of the wood leaving for little to collect. I have been watching mine as I run at 170 with a 15 degree swing and even with a freshly loaded firebox and return temps around 140 have yet to see any moisture inside. I believe with the return coming in the top where the hottest water is and where my temp probe is that the water around the water jacket just never drops to the 140 magic number be cause when the return temp drops to the set point the burn cycle starts and won't allow the overall temp to drop, large deltas or return lines to the bottom would make this a real problem.

[MattyNH]

I got a friend of mine..That has a aqua-therm s-275..Long story short the guy before him (pervious owner of the house, boiler )hooked it up with the most cheapest way of doing it.. Its unbelievable awful..Well the guy hook the baseboard directly to the owb boiler..The only stat setting is on the owb boiler..He has to keep his boiler at like 100-120F.. Other wise it will blow him out of the house..Yeah burning green wood he was doing..He had a lot of water coming out of the ash door..Once he changed his wood to dry he hasn't had a problem with water that I've heard....I believe he's gonna redo everything this year

[RSI]

I got a friend of mine..That has a aqua-therm s-275..Long story short the guy before him (pervious owner of the house, boiler )hooked it up with the most cheapest way of doing it.. Its unbelievable awful..Well the guy hook the baseboard directly to the owb boiler..The only stat setting is on the owb boiler..He has to keep his boiler at like 100-120F.. Other wise it will blow him out of the house..Yeah burning green wood he was doing..He had a lot of water coming out of the ash door..Once he changed his wood to dry he hasn't had a problem with water that I've heard....I believe he's gonna redo everything this year

That would be an easy fix. Either add a 3 way zone valve or another pump.
Does he heat the DHW? Probably not working too well if he does at that temp.

[MattyNH]

I wanna say he is.  But not 100% on that .. He's gonna move the boiler and put the correct piping and everything this summer

[Scott7m]

I think the longer differential is harder on the steel also. 15 degree and more just allows the moisture to soak in versus a 10 degree since the stove will run more often which decreases the moisture.

Water soak in from where???

If you really wanna see a mess set your differential down to 1-2 degrees where it always has a small lazy fire and never gets hot enough to cook off some creosote inside the stove, a stove that idles all the time is far dirtier, hard working stoves stay cleaner in general

With a differential of 10-15 degrees, the fire should get hot enough to clean up the creosote that formed during idle, but fires that burn for signifacantly less time, don't get as hot and lead to more creosote

Wood burns most efficient when it's burning hot and is able to burn some gases, that's why batch burn units are efficient like "Garn" yet models like empyre 400 or similar maintain high temps by storing the heat in the refractory, fire needs fuel, o2, and heat.  The fuel is the wood, air is only introduced in a gasser when the fan is on, the heat is stored, so when it's time to fire it's ready to go