Can I improve my metal box stoves?

I have two of the typical box stoves in my house, and I must say that they don't produce heat worth a darn. Both are quite new, the chimneys are all to code and clean. My firewood is typically fir - it's the best I can find on the island here. Occasionally I can get Arbutus, which is lovely firewood, but everyone else here is after the same wood, so....
Most of the firewood comes from driftwood logs out of the ocean. It gets cut, split and stacked and it doesn't get used until it is dry. The driftwood might be fir, hemlock, spruce or who knows what.
Conversely, in my small cabin, I have one small box stove 17 years old, and it works like a charm! Takes the cabin from cold to toasty in well under half an hour. The cabin is 432 square feet on the main floor and about another 350 up in the loft. Only 2 x 4 walls, insulated, but I'm sure they do leak air.
The big house totals around 2,300 square feet on both floors, and the stove manufacturers claim that the stoves will each heat 1,500 square feet. Theoretically, they should do the job. But in the real world? Not a chance. All 2 x 6 well insulated construction, but lots of windows.
The house is presently for sale, and I'm reluctant to add a RMH in place of either of them, but if the house doesn't sell by the early fall my reluctance could vanish in a heartbeat.
In the mean time, is there some way that I can add some real mass in the form of masonry to these stoves to improve the performance?
I will try and attach pics of the stoves in question.
The first one is on the main floor in the living room. Although the whole main floor is actually wide open.
The second one is in what I call the breakfast nook and is down 4 steps from the main floor. This one sits on a tile covered brick floor, and the tile you see behind the stove also covers a solid brick wall. But unless either of these stoves has been running all day long, they just don't seem to heat worth a darn.
Thanks in advance for any advice that you may have.

have you thought about curtains ? I think you guys may know them as drapes as well as pelmets, windowsills and maybe storm shutters ?

Or moving the fires away from outside walls

Hello David:

It isn't possible to move either of the wood stoves unfortunately.

I do have blinds on most, but not all, of the windows. It doesn't seem to help that much. I have purchased some sheets of 1" thick foil-faced foam to make covers for some of the windows this winter. They will be a push fit in between the window casings.

The real problem is the lack of heat that these stoves produce, and I think that there must be a way to get a lot more heat out of them.

Storm shutters on the outside might be a good idea, but I really don't want to spend a ton more money for something like that. I'm of the opinion that the foil-faced foam will do a better job there.

Many thanks for your reply.

What about the chimneys ?
Are they taking most of the heat away ? Any chance of doing something there like having more pipe in the room to give off heat ?
I am not talking about blinds but old fashioned lined curtains on doors and windows. Plus a box at the top to stop convection current ie drafts around the window developing . You can take them with you when you move

David

Hi David:

I expect the chimneys are taking a fair bit of the heat outside, but that's the way these box types work I think. One of them has about 15 feet of chimney inside the house, the other about 8 feet before they go through the roof.

I do like the idea of heavy, lined curtains on the doors. There are 6 doors on exterior walls of this place. That could make quite a difference. Thanks for that idea.

You can stack rocks on the top as long as they are heat tolerant. Granite countertop scraps (sink cutouts, rough edges, corners, goofs, etc) can be had for the hauling if you are lucky, for a few dollars if you have to pay.

You can get big stockpots fairly cheap, the tall skinny turkey cooker ones would be good. A couple filled with water setting beside the stove will hold a LOT of heat.

R Scott wrote:You can stack rocks on the top as long as they are heat tolerant. Granite countertop scraps (sink cutouts, rough edges, corners, goofs, etc) can be had for the hauling if you are lucky, for a few dollars if you have to pay.

You can get big stockpots fairly cheap, the tall skinny turkey cooker ones would be good. A couple filled with water setting beside the stove will hold a LOT of heat.

We do have a fair amount of granite rocks here. The actual island itself is nothing more than sandstone, and much of the top of it is degraded sandstone mixed with dead vegetation. I will see if I can find a few big granite rocks and see how they do.

I do already routinely use big pots of water, as much to provide extra humidity as anything else.

I just remembered that several years ago I picked up an old Fisher stove from a friend. It was intended to be pressed into service to heat the hot tub. One of those things that never got done. The Fisher's that I remember from 30+ years ago really did crank out some heat. So I'm going to drag this one out, spend some time giving it a good cleaning and see what develops. I don't think this one has been run for a good 20 years.

I took a look at both stoves today, and one has some sort of blockage between the baffle and the flue. Once that is fixed it might not be so bad. But my friend, who stayed here last winter while I was away seemed to be burning garbage in the stove. I broke a 1 1/2" thick layer of some sort of conglomerate off the stove bottom full of metal lids off of food cans and all manner of other detritus. What a mess. The other stove I gave a good cleaning to, and it does work, just not very well. But after I got it going I put several concrete slabs on top, and it will be interesting to see how long they give off heat for. It's a start.

I do believe I have found the trouble. The lower stove just needed a good cleanout and it's good.

However, the living room stove was another matter entirely. It turns out that this stove has a whole series of baffles inside, and once they get clogged up, there is no way to clean them. I don't think much of the design I can tell you. So considering that the stove is essentially useless now, I figured I had nothing to lose by seeing what could be done inside to repair the trouble.

Long story short, I took out some of the steel inside, gave everything a thorough cleaning - at least where I could get in with a variety of cobbled up tools - and I have a test fire going now. It has been running nearly 3 hours and it has never run anywhere near this well in the past. Plus I have just over 100 pounds of concrete bricks sitting on the stove top getting warm. I may have this one beat after all.