A possible trade-off would be to get a condensing water heater.
I just installed a 95% efficient condensing boiler in my accessory building.
The advantages are the increased efficiency ... about 5% more than the non-condensing version ... and the fact that it uses cheap and easy to glue together PVC pipe for the intake and the exhaust.
The disadvantage is the extra up-front cost of the boiler.
Another disadvantage is the need for a condensate drain. If you are lucky there will be a drain close to where the combustion takes place. That is the case for the furnace in the house basement. The condensate runs down a tube and into a floor drain. If you are not lucky then there is no drain handy ... like in the accessory building ... and a condensate pump is required. It has a 1 quart or so reservoir and a level sensor. When the level is reached a small pump turns on and the condensate is pumped thru 15 feet of tubing, eventually exiting the building thru the wall. The 'condensate rabbit hole' down which I went then needs to solve the "It's Minnesota and the condensate drain may freeze where it exits the building" problem but I am now so far off topic that I may not be able to find my way back.
In my case the higher initial cost was offset over the lifetime of the boiler by the efficiency and offset immediately by the price of PVC vs stainless. A non-monetary offset to the up-front costs is the ease of installation with PVC. Not only is it easy to cut and glue compared to stainless steel but if you do it in a small enclosed space you can get a mild high from the vapors
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Arvid
I just installed a 95% efficient condensing boiler in my accessory building.
The advantages are the increased efficiency ... about 5% more than the non-condensing version ... and the fact that it uses cheap and easy to glue together PVC pipe for the intake and the exhaust.
The disadvantage is the extra up-front cost of the boiler.
Another disadvantage is the need for a condensate drain. If you are lucky there will be a drain close to where the combustion takes place. That is the case for the furnace in the house basement. The condensate runs down a tube and into a floor drain. If you are not lucky then there is no drain handy ... like in the accessory building ... and a condensate pump is required. It has a 1 quart or so reservoir and a level sensor. When the level is reached a small pump turns on and the condensate is pumped thru 15 feet of tubing, eventually exiting the building thru the wall. The 'condensate rabbit hole' down which I went then needs to solve the "It's Minnesota and the condensate drain may freeze where it exits the building" problem but I am now so far off topic that I may not be able to find my way back.
In my case the higher initial cost was offset over the lifetime of the boiler by the efficiency and offset immediately by the price of PVC vs stainless. A non-monetary offset to the up-front costs is the ease of installation with PVC. Not only is it easy to cut and glue compared to stainless steel but if you do it in a small enclosed space you can get a mild high from the vapors
.Arvid