Wood Master

3fordasho

Minister of Fire
Jul 20, 2007
997
South Central Minnesota
Reading articles on this forum and others you get many conflicting opinions about products, warranties and Customer service. I do not see many articles ore reviews about Polar furnaces. I compared their warranty and product specs to the cleanfire and the cleanfire came out ahead. I will keep searching for info on both units or if another option comes up. I am looking for 170-200+Kbtu's, 250+ gallons of water storage, and indoor installation. The Garn looked interesting but it is an open system that pisses steam everywhere, this unit will be installed close to some neighbors. The search continues!
I've never heard that a Garn leaks steam everywhere, at least no more than any other open system. Now there are some pros and cons to an open system, the cost of water treatment and ongoing water testing being a con to an open system. Closed (pressurized) systems probably will have a longer life, I just don't know of any that are packaged in an outdoor boiler type package. I saw enough cons to an open system that both my shop and house systems are closed systems.
 
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TCaldwell

Minister of Fire
The “pissing steam all over” is not quite accurate. Upon first water filling or subsequent ones maybe once a year, as the water expands due to the first fire thereafter it will leak out the dedicated overflow tube into a 5 gallon bucket. The steam and water might last 15 minutes out of the first burn after a water refill. This is not unique to the garn, all outdoor unpressurized wood boilers have a vent pipe for the same purpose.
 

E Yoder

Minister of Fire
Jan 27, 2017
533
Floyd, VA
An open to the atmosphere wood "boiler" should never steam. If it's running over it was overfilled, which will soon level out and in the future don't fill full while cold. The water will expand as it heats up.
If it actually steams it's leaking air into the fire and overheating, which needs to be corrected, it's not normal. Usually a leaky gasket or damper flap. I haven't seen mine steam in years, I have it set to shut off at 180F, well below steam.
 

TCaldwell

Minister of Fire
Yoder, your correct on both counts, however when a garn holds 2000 gal water, the thermal expansion will be more, almost insuring a little overflow at startup
 

Joncombat

Member
Dec 28, 2018
34
Danbury ct
My Garn 2000 has white smoke (steam) coming out the chimney for the first 10-15 minutes of the burn depending on outdoor temperature. This is moisture from the wood- not related to it being an open system.

For the last two weeks I am down to one fire every other day, (wagon of wood). I'm in Rhode Island , so similar climate. Thermal storage, Outdoor Reset and not heating domestic hot water is the way to go.

I typically burn at night when I get home from work- neighbors can't see steam in the dark.
I plan on heating my hot water with it also. I believe Garn batch burns like most boilers do. what happens if you are half way through your wood and all your water is at temperature? Do the unit shut off or does it dump the heat on a zone so it does not overheat?

On another note, Heatmaster contacted me and indicated they are retesting in May. Hopefully their efficiency will be 75% or greater for the tax rebate.
 

3fordasho

Minister of Fire
Jul 20, 2007
997
South Central Minnesota
I plan on heating my hot water with it also. I believe Garn batch burns like most boilers do. what happens if you are half way through your wood and all your water is at temperature? Do the unit shut off or does it dump the heat on a zone so it does not overheat?
Not sure what a Garn does but my system does the following:
At 190F jacket temp the boiler goes into overheat mode - inducer fan shuts off and primary and secondary inlets shut down but one of the two stays partially open. Circulator pump stays running and once boiler temp drops a few degrees the boiler will resume normal operation.

If boiler temps continue to climb and jacket temps start to approach 212F there is a thermostatically/mechanically actuated valve that will open and flood the overheat loop built into the boiler with domestic cold water.

I don't use a dump zone in my system but that is another solution to an overheat situation.
 

Joncombat

Member
Dec 28, 2018
34
Danbury ct
Not sure what a Garn does but my system does the following:
At 190F jacket temp the boiler goes into overheat mode - inducer fan shuts off and primary and secondary inlets shut down but one of the two stays partially open. Circulator pump stays running and once boiler temp drops a few degrees the boiler will resume normal operation.

If boiler temps continue to climb and jacket temps start to approach 212F there is a thermostatically/mechanically actuated valve that will open and flood the overheat loop built into the boiler with domestic cold water.

I don't use a dump zone in my system but that is another solution to an overheat situation.
I have a garage and basement slab with radiant heat that I can use as a dump zone. If you flood the hot boiler with cold water will it crack? also, if your system is "full" where does the extra water go? you will need a safe place to dump the hot water.
 

3fordasho

Minister of Fire
Jul 20, 2007
997
South Central Minnesota
I have a garage and basement slab with radiant heat that I can use as a dump zone. If you flood the hot boiler with cold water will it crack? also, if your system is "full" where does the extra water go? you will need a safe place to dump the hot water.
It doesn't flood the boiler with cold water, there is a dedicated loop of piping in the top of the boiler jacket that is meant for this purpose.
As far as I know most all euro design boilers are equipped with it. The valve opens when the high temp is reached, it runs cold water through the loop of internal tubing and then back out to a drain or even dump outside the building.
 

maple1

Minister of Fire
Sep 15, 2011
10,746
Nova Scotia
I have a garage and basement slab with radiant heat that I can use as a dump zone. If you flood the hot boiler with cold water will it crack? also, if your system is "full" where does the extra water go? you will need a safe place to dump the hot water.
I would not do that for a dump zone. One of the main ways for your boiler to overheat is if the power goes out in the middle of a hot burn and your circs stop pumping. A zone right above the boiler that can convect without a circ running, with a normally open zone valve in between also tied to an aquastat that could also open the ZV on a high temp would be the best approach.
 

S.Whiplash

Member
Oct 28, 2012
113
I would not do that for a dump zone. One of the main ways for your boiler to overheat is if the power goes out in the middle of a hot burn and your circs stop pumping. A zone right above the boiler that can convect without a circ running, with a normally open zone valve in between also tied to an aquastat that could also open the ZV on a high temp would be the best approach.

Yes exactly, it's a safety mechanism for dumping heat which equates to pressure, not water.
 

S.Whiplash

Member
Oct 28, 2012
113
I plan on heating my hot water with it also. I believe Garn batch burns like most boilers do. what happens if you are half way through your wood and all your water is at temperature? Do the unit shut off or does it dump the heat on a zone so it does not overheat?

On another note, Heatmaster contacted me and indicated they are retesting in May. Hopefully their efficiency will be 75% or greater for the tax rebate.
This would be an indication that you miscalculated your wood load in regard to temperature, a mistake most Garn owners only make a few times. On the front of the Garn is an over-flow tube that will drain hot water back at your feet if it expands too much, if a bucket is handy it can be caught and poured back into the tank once it cools down.

One misnomer above, I believe the Garn is the only true batch burner on the market today. A batch burner is designed to burn through it's entire fuel load without ever damping down the fire, which is by far the most efficient way to burn wood, flat out. A Garn can do this because it has enough built in thermal storage capacity to absorb all of the energy from the fire at the same rate it is produced. Other brands only begin to replicate this system by adding exterior thermal storage to a capacity of 1000 gals. or more.
 

maple1

Minister of Fire
Sep 15, 2011
10,746
Nova Scotia
This would be an indication that you miscalculated your wood load in regard to temperature, a mistake most Garn owners only make a few times. On the front of the Garn is an over-flow tube that will drain hot water back at your feet if it expands too much, if a bucket is handy it can be caught and poured back into the tank once it cools down.

One misnomer above, I believe the Garn is the only true batch burner on the market today. A batch burner is designed to burn through it's entire fuel load without ever damping down the fire, which is by far the most efficient way to burn wood, flat out. A Garn can do this because it has enough built in thermal storage capacity to absorb all of the energy from the fire at the same rate it is produced. Other brands only begin to replicate this system by adding exterior thermal storage to a capacity of 1000 gals. or more.
Some semantics there. If the installation instructions of one of the other boilers specifically and strictly calls for storage tanks, I'd say it's a batch burner.
 

salecker

Minister of Fire
Aug 22, 2010
1,395
Northern Canada
And if you have storage,then you don't need a dump zone.
 

Case1030

Feeling the Heat
Dec 12, 2017
360
Manitoba
I promised a video.

No bypass damper needed. Soon as you open the door ECM fan kicks to high speed. No smoke at all even in mid burn.

Shows the ignition door and peak of the Vortex chamber.

Edit: The background noise is the garage blower fan. The boiler is very quiet.

 
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Case1030

Feeling the Heat
Dec 12, 2017
360
Manitoba
Easy to access turbulators for end of the year maintenance/ cleaning.

20210424_140404.jpg 20210424_132832.jpg
 
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SpaceBus

Minister of Fire
Nov 18, 2018
5,756
Downeast Maine
Looks like a nice unit. Is the Polar like an outdoor gasser in that the thermal storage is built into the appliance?
 

Case1030

Feeling the Heat
Dec 12, 2017
360
Manitoba
Looks like a nice unit. Is the Polar like an outdoor gasser in that the thermal storage is built into the appliance?
Yes it's an Indoor/Outdoor approved gasser. Very similar to the Froling. It has 200 gallons built in. I'd consider it more of a buffer storage to even out burns cycles.

In the next few days I'll make an effort to get a cold relight video up demonstrating how great it works. The middle ignition door is a huge benefit. I didn't really know how useful it was until I tried it myself.

Can do a relight right at the nozzle with kindling and a torch in a few mins. Smokeless after about about 3-5 mins with dry wood. So far quickest light times. I noticed the fan will ramp up RPM if it feels a blockage at the nozzle.
 

SpaceBus

Minister of Fire
Nov 18, 2018
5,756
Downeast Maine
Yes it's an Indoor/Outdoor approved gasser. Very similar to the Froling. It has 200 gallons built in. I'd consider it more of a buffer storage to even out burns cycles.

In the next few days I'll make an effort to get a cold relight video up demonstrating how great it works. The middle ignition door is a huge benefit. I didn't really know how useful it was until I tried it myself.

Can do a relight right at the nozzle with kindling and a torch in a few mins. Smokeless after about about 3-5 mins with dry wood. So far quickest light times. I noticed the fan will ramp up RPM if it feels a blockage at the nozzle.
Someday I'd like to have a heated garage and greenhouse, by that time this will probably be one of the only EPA approved gassers!
 

salecker

Minister of Fire
Aug 22, 2010
1,395
Northern Canada
I doubt that...
 

E Yoder

Minister of Fire
Jan 27, 2017
533
Floyd, VA
I don't think the epa will squeeze it down to 1 brand of gasser (I think that's what you meant). A bit of pressure makes you innovate.
Example: Heatmaster redesigned the G series in 2020 and tested and passed. Then spent another year tuning and got even better. The numbers they're getting now would have been considered impossible a few years ago. I'm guessing the other manufacturers are doing the same thing.
 

SpaceBus

Minister of Fire
Nov 18, 2018
5,756
Downeast Maine
I don't think the epa will squeeze it down to 1 brand of gasser (I think that's what you meant). A bit of pressure makes you innovate.
Example: Heatmaster redesigned the G series in 2020 and tested and passed. Then spent another year tuning and got even better. The numbers they're getting now would have been considered impossible a few years ago. I'm guessing the other manufacturers are doing the same thing.
I hope they do continue to innovate, but many do not and simply close their doors.
 

salecker

Minister of Fire
Aug 22, 2010
1,395
Northern Canada
Econoburn was ready to start certification,then covid showed up.
The certification process involved labs in Canada,so that complicates it during these unprecedented times.But as the fearless leeders of our countries always say "we are in this together"!!!
 
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Case1030

Feeling the Heat
Dec 12, 2017
360
Manitoba
 

E Yoder

Minister of Fire
Jan 27, 2017
533
Floyd, VA
To be clear, I'm not advocating for more regulation at all, it will squeeze the smaller guys for sure. Look at car manufacturers in the early-mid 1900's. A slew of names gone.
My point is we still have cars to drive. There are winners and losers.
 
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