Room air vent temperature

[Snowy Rivers]

This morning I did the early A M pot cleaning on the Little Prodigy and decided after is was back cooking along that I would measure the outlet air temp.

On the LOW (1) setting the air temp in front of the vent is 160F
The airflow is pretty low at this setting too.

The fan is rated at 150 CFM maximum free air and I would guess that on number 1 it is about half or less of that volume.

On high setting (5) the temp goes to near 200F

I never run the stove at that setting though.

Normally 1 is the sweet spot and on a cold night for the first hour, I my select 2

The stoves hopper is so small that I like to keep the feed rat low so it will make it through the night from 11 P M to about 9 A M without needing fuel.


One soap bucket of shells will fill the little creature chuck full.

The Advantage in number 1 blows a little cooler at the vent but delivers a lot more CFM of air.

Just some Numbers.

Snowy

 

[tjnamtiw]

I am in the midst of an experiment with my Castile and I find with a low feed rate on Medium blower speed, my outlet air temperature is 150 degrees so we are close. My exhaust temp measured right on the outlet of the blower manifold where it mates with the flexible exhaust pipe up the chimney is 170 degrees. I'm using an old surface contact pyrometer that I used to use at work before we went to infrared measuring devices. One word of caution to those using infrared devices. There should be a setting on them for 'dark' and 'shiny' surfaces. If it is set incorrectly, you will get really bogus numbers. If it doesn't have such a setting then take the numbers with a grain of salt.

 

[Snowy Rivers]

Seems that the oulet temps are a tad higher than whats going into the room.

A secondary heat exchanger to glean more of the heat energy from the fuel burned would be a great plus.

My Prodigy has a fairly cool exhaust temp and my pipe is only 2 feet long from the stove to its terminus outside.

The air is just warm as it exits the pipe.

The secondary heat scavenger could be made of aluminum to easily pick up the heat.

Stoves like the Quadrafire use a multi finned exchanger with fins on both sides of a heavy aluminum plate.

Aluminum tubes with fins would be great other than its tough to clean them.

The Whitfields have a manually actuated scrapper device that slides over the tubes when a handle is pulled.


Would be interesting to see how efficient the different stoves are at getting the most heat from the fire into the room.

Snowy

 

[tjnamtiw]

That's exactly what disappoints me about the caveman heat exchanger design of my Sante Fe and Castile, Snowy. I have potentially more heat going up the stack than into the room! I think the only Quad that uses multifins is the Mt. Vernon. Mine are just smooth aluminum pipes trying their best to pick up the heat and transfer it to the air that is blowing up the tubes. Your scavenger idea is the old box idea, I think, that people put into the flue pipe above a wood burning stove. Can't do that with my inserts. (
I am going to put some springs into my tubes to break up the airflow and mix the hot, outer layer with the cooler center portion of the air. I will be doing some analysis to see if it works. Springs should be here Tuesday. Of course, it's going to be back in the 70's!! It was 29 this morning in Georgia.
Yes, I wish Quad had at least used finned tubing or corrugated piping that would present more surface area to absorb the heat. The stoves are great but the heat exchange design is 50 years old.

If I were out of warranty and the tubes were steel, I would be welding fins onto them. they have the scrapers on them like you have so the fins would negate the scrapers.

 

[Snowy Rivers]

The Quads we have here are the older 1000 series, Circa 1993/94

Been great stoves. Only issues were the original ceramic firepots would crack and the bottom would fall into the air plenum.

They offered an all steel pot that was a direct replacement item under warranty.

The ceramic igniter was very fragile and was subject to failure.
They offered a redesigned metal half loop type igniter that works well.

These new igniters last well too.

Other than those two issues the 1000 series has served really well.

For several years we used the Quad almost 100% for the shoulder seasons.

Now I only fire the one upstairs if the house is really cold and I need max heat right now or if we have to go away for an overnighter and can't be here to tend the manual stoves.

I would bet that the cost of those original aluminum heat exchangers was $$$$$$$$$$

They are an aluminum plate with fins welded on both sides, Possibly an extrusion ??? not sure.

The heat that those critters throw out will burn your hand within a foot of the outlet.

Very good stoves, tad noisy is all I could say negative. We have ours way over on one side of the house far away from where we spend much time, so its no biggy.

Snowy

 

[tjnamtiw]

sounds like they took a step backwards with the heat exchanger. I worked with aluminum extrusions for some of the automation equipment in my plants and I thought about it as a better design. hmmmm. Well, I'm stuck with what I have so I will live with it.