Originally Posted by Cheechako
A 150 watt light bulb cirrently heats my fresh water
pumphouse. We have been in the teens at night and not over freezing in the day for several days now. The pumphouse is fine. Which only means really it's all about insulation
and size of enclosure.
I have just purchased another Davis Drier I will replace the bulb with, (like a little 170 watt heater with no fan) although I've used the bulb for years, you just dont know when it will burn out.. Whether you use a Goldenrod, Caframo or Davis unit, it's all about the wattage you need. The Goldenrod only comes in 38 watts for the largest one. The Davis goes up to I think 170 watts.
Hello Cheechako. The amount of heat required to heat your space depends on several factors. What is the design temperature (ie -4 deg F), what is the boat insulation factor in either U value or R value, what are the internal sources of heat such as people and equipment
, and lastly what is the desired space temperature that you want to achieve. Keep in mind that one kilowatt is equivalent to 3414 btu of heat.
A general rule
of thumb for a building space is as follows:
BTU=Area X 1.08 X (T1-T2)
So a room 10ft X 10ft has a total volume of 1000 cubic feet and the temperature differential might be from 32 deg f to 70 deg f = 38 deg
BTU=1000 X 1.08 X 38
= 41,040 BTUs or 12 Kilowatts of energy or 80 150w lightbulbs.
Now a boat is different than a room with nothing in it and the variables change such as your fresh water pump house generates heat when the pump is activated and the space is much smaller.
It does come down to trial and what works and you have fortunately gone through all the trials.