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What size water heater for 200sf system?

Your professional opinion will be appreciated.
What size water heater should i use on the below described system?
200sf area, heat loss of less than 9,000 btu/hr, 1/2” pex staple up w/ transfer plates, 2 loops of 150’ (300lf total), single zone, crawlspace installation, north missouri, crawlspace to be insulated, joist bays to be insulated.
See attached photo for reference.
My questions are:
What size tank style water heater should i use? Due to space it needs to be a short 30 gallon or less.
What size elements?
What size water heater should i use on the below described system?
200sf area, heat loss of less than 9,000 btu/hr, 1/2” pex staple up w/ transfer plates, 2 loops of 150’ (300lf total), single zone, crawlspace installation, north missouri, crawlspace to be insulated, joist bays to be insulated.
See attached photo for reference.
My questions are:
What size tank style water heater should i use? Due to space it needs to be a short 30 gallon or less.
What size elements?
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Comments
That being said. To covert from Btu's to watts, divide by 3.412. Keep in mind that electric water heater will only run element at a time so you only want to calculate the output of one element, not both.
Albert Einstein
An electric tank with a 1500W element= 1500 X 3.41= 5115 btu/hr.
Most small, off the shelf 6 or 10 gallon tanks have a single, 1650W 120V element, 5626 btu/hr
trainer for Caleffi NA
Living the hydronic dream
This is a tiny house/cabin quality built, small but very nice. The primary heat will be the radiant floor heat. Previously was heated by a 10,000 btu wall mounted lp gas heater.
On low would run you out, and my son keeps his bedroom window open as that heat was not good for a loft bedroom.
thanks!
And, I am fully aware that a wall mounted gas heater should not be used a primary source of heat. This will become backup only in case of power outage.
With electric tanks, an inexpensive element change-out can quickly increase or decrease output.
Modulating electric boilers are another option for an appliance that could adjust it's output to the ever-changing load.
trainer for Caleffi NA
Living the hydronic dream