OK. Cabin Fever is getting me too.
Anyway.
I don't see why you want a pump. At all.
This is all related to the photo below.
It is coal fired. Single layer top and bottom. The water jacket is maybe 2" thick, around the diameter.
The output is the high pipe. The intake is the low pipe.
The storage tank is a standard 40 gallon gas water heater. They don't have gas.
I "think" (I don't recall)...
The output of the coal heater goes into the gas heater's relief valve hole.
There is still a relief valve there!
The input of the coal heater comes from the gas heater's drain valve hole.
The aquastat/thermostat thing controls the draft. It pulls the chain up and down. No idea if the thermometer is actually connected to the same draft control device.
About 10~15 minutes from fire out, dead cold, and the water is hot enough to shower without ANY complaints from teenage girls.
Best I can say.
"Takes a coffee can of coal a day".
"Doesn't often pop-off". Translation- Sometimes it will, guessing once or twice a year.
Supplied a family of 6 or 8 with plenty of hot water, showering one after another.
There is no pump.
I know of a few that are connected to the wood or coal heating systems of quite large houses.
None have a pump.
To avoid 'pop-off' they use a short (10'?) hot water base board heater section, high (4~5 feet) above the heater. This is controlled by a manual valve.
If the outside temperature is cold, they "crack" the valve.
If the outside temperature is VERY cold, they open the valve.
If the outside temperature is warmer, they close the valve.
I take it the concept is if the outside is very cold, the wood burner is running faster than they use hot water.
And if it is not so cold, the wood burner won't make enough heat to boil the water.
Where are you? I might be able to find someone who can recommend someone in your area.
G-
