Friday, April 30, 2021

In Praise of the Margin Gem's Waterfront

Things have been ridiculously busy in our lives over the last several weeks.  School has kept me occupied with both substituting and accompanying the choirs; our church has hired a pastor; after a futile housing hunt we prepared our little house here on the farm for him and his wife to live in; and our church is converting a former doctor's office into our new church building.

You will note from the list above that I haven't done any spring gardening or cleaning, and I didn't even put mowing on the list, though the yard is beginning to look like a jungle.  All of these necessary activities have prevented me from posting very regularly.

Through it all, we've still managed to be firing the Margin Gem on a daily basis.  My goal is to have it heat all of our hot water until the end of May, but we shall see.  Lots of factors play into this, such as how much time I have to keep gathering and cutting fuel, how hot the weather becomes, the levels of humidity indoors and out, whether I can keep enough dry fuel ahead, etc.

Today, though, I just wanted to write a quick post to say how truly impressed I am by the water heating capacity of our Margin Gem system.  In something I read or watched or in a phone conversation with Daniel Fenoff of Stoves and More LLC, where we purchased our Margin Gem back in 2011, I remember him saying that during the summer months they lit a fire in their cookstove each morning in order to cook breakfast.  That fire heated enough water to meet their hot water needs until they had another fire in the evening to cook supper.  

With our schedule as full as it has been, we haven't been doing a lot of cooking.  Last night we had a cold supper, for example, and the night before that, all I made was a dish that my niece calls "Bougie Ramen."  As that involves simply boiling water for three minutes, it was far faster to cook it on the electric stove down in the basement.  Thus, what we've been doing is not starting a fire in the cookstove until just before we go to bed.  Once the fire is well established, I put large chunks of wood in the stove and turn the draft down so that the fire will burn all night.  When we get up in the morning, there is a nice bed of coals that I rake together.  I throw some kindling on this, wait a few minutes after it has caught fire, and throw a few more small pieces in.  This fire is sufficient to fry a couple eggs or make French toast, and it tops off the hot water enough that we can shower and wash dishes in the mornings.

(Note: The above firing method of firing the cookstove can create an unduly large accumulation of creosote in the chimney.  In order to prevent that, I have to use the driest wood that I can find.)

You don't have to have a very hot fire in order to heat quite a bit of water.  I think this is due to the large surface area of the Margin Gem's waterfront.

The interior of the Margin Gem firebox.

In the picture above, you can kind of see the waterfront.  It is the whole left side of the Margin Gem's firebox and measures approximately 16" x 12" which results in about 192 square inches of heat exchanging space.  Coupled with a stone-lined 40-gallon Vaughn range boiler, the heating capacity of this system is impressive, I think.

A picture of the Vaughn range boiler before it
was attached to the Margin Gem.

If I were going to level any complaint against this water system of ours, it would be at the mixing valve which tempers the water as it leaves the tank and goes into the house plumbing.  

Our problematic mixing valve.

Sometimes in the middle of a shower (and perhaps it does this at other times too, but we have no way of knowing) it behaves badly, sending the water from very pleasant to too cold to uncomfortably hot for no apparent reason.  We notice that this happens most frequently when the water in the tank is extremely hot.  I believe this little defect to be the result of the fact that it was damaged by the plumber during installation.  While this is annoying, it hasn't proven to be dangerous, and getting it replaced will not necessarily be expensive, but it will be colossally inconvenient.

The longterm weather forecast is for fairly cool weather, so we'll see how long we can hold out until we switch to electrically heated water for the summer.


  1. Jim,

    I've compared your experience heating water with your Margin Gem to ours with our Kitchen Queen before, and was impressed by the Gem's superior performance. Now I see why. The Kitchen Queen uses 3/4 inch plumbing pipe as its heat exchanger. There might be 32 inches of pipe and two elbows. It's hard to know what the surface area of the elbows is, but the area of the outside of the pipes is hardly more than half the surface area of your heat exchanger. And the areas are not comparable because all your area is facing the flames (radiant energy), but the same is not true of my pipes (you get better radiant heat exchange).

    Our Waterford Stanley has a heat exchanger about half the size of yours -- about 8 3/4" x 12". We have never fired that stove, so I have no observations regarding its performance.

    However, good or bad performance, we still miss the hot water during the off-season!

  2. Hi, Brett!

    I've seen other stoves outfitted with a pipe like the Kitchen Queen, and I didn't think they could possibly heat water as efficiently as the Margin Gem's waterfront. It really is a great design. The waterfront on the Elmira/Heartland Ovals and Sweethearts was constructed quite similarly to the Margin Gem's.

    The old Monarch that my great-great-grandparents had was equipped with a waterfront too, only it was in the back of the firebox where the rear liner would have been. Thus, it had only about a six or seven inch square (total of 36" - 49" surface area) that was exposed to the fire. No one ever complained that it was inadequate within my hearing, though. Such a smart way to make dual use of the cooking fire!

  3. Thanks for this blog Jim - It's one of my all-time favorites. Do you know if you can retrofit a gem with the water jacket?

    1. Hi, Greg! Excellent question, but unfortunately, I don't know the answer. I would call Daniel at He was the one I asked about whether I could change my Margin Gem's firebox to burn coal, and he got me an answer right away. Good luck!