i would consider a new heater and have it plumbed from the main tank. i had one in the old shop and they had to put a regulator on the shop wall where it went in..also at the house where it went in there.. alot of folks like the modine heaters or the hot dawgs i think they are called. they do have a online web page i dont have it but have been there..i am now using a furnace but there might be some used trailer furnaces around you for a reasonable cost
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