heating a car wash

first season heating my house with a 520,absolutely love it.i have a two bay self serve car wash.thinking about switching from propane to coal.propane about3.10 per gallon.its killing me.190,000 btu.think a 520 will do the job?

190K is the upper limit of the 520 capacity, but it should be attainable. Since you'd be using some sort of heat exchanger, possibly a flat plate exchanger, you'd have to do some more calculations.

I assume your need is for heating water used for washing the cars. Since the use of the water is somewhat intermittent, perhaps an industrial sized version of an indirect hot water heater would allow some buffering of the BTU load.

Figure out your peak demand in gallons per minute, and find a Superstore tank that will meet the need. Do you recycle the water? If so the temp of the water going back to the heater will be a bit higher, which will help out. The other thing you could do is have a 100 gallon hot water tank (well insulated) that is kept awfully hot (say 180) with a circulator pump and a tempering valve to knock the temperature down to something less than lethal. Now there is always a huge amount ready to go, and the boiler should be able to keep up even under the heaviest demand.

Mike

Run two in parallel. They might work more efficient in the lower range Scott

the temp of the water doesnt need to be above 120 degrees.the propane heater is 120 gallons.i could use that for storage.