Need Propane Hot Water Control Help

Harley

I am modifying a 40 gallon propane hot water tank
to be a chicken scalder for the farm. I need to change the controls and valve so that I hold a steady 150 degrees, instead of fluctuating between a high and low point.
I have been told I need to change the valve into a combination
gas valve and install a ETC and probe in immersion well.
Any other way to get the tank to stay in a more narrow range
than the stock controls without such a major overhaul?
Please recommend what items you would use.
thanks.

carol_3

I can't be sure what your application is, but I'll take a guess based on how things usually are. Chances are that your gas valve already is a combination gas valve. Anyway, the valve doesn't control the temperature. It just controls whether or not there's gas available to make a flame. The temp controller is probably an aquastat. Unfortunately for what you have in mind, the temp range of an aquastat is often in the 15-20 degree range. You might need to find a plumber who knows controls to come up with a tighter temp controller.

Harley

I believe the gas valves that come on the propane hot water are self regulated in a range. I am trying to find the simplest way to get a tighter control on the range and set it at 150 degrees +- 5 degrees.

Larry Weingarten

Normal water heater...

... controls can have a dead band of 30 degrees these days. I don't know of a way to use the standard millivolt control to get the tight range you want. Electronic set point thermostats can control closely though. How about using one to control a simple on/off 24 volt gas valve?

Being a plumber, I get to weigh in :~) Any talk of things warm or hot will likely cheer Carol, who was staying cool in Antarctica last I knew.

Yours, Larry

bill_71

how about setting that water heater gas valve all the way up...(should be around 160 or so in temp)and pipe in a mixing valve to keep a constant supply of 150 degree water. that should lessen your swing to about close to 5 degrees....its not the way a water heater is intended to work and for the safety of those chickens PLEASE don't plug up the relief valve if and when it starts dripping

Harley

Pressure relief is not a problem. We cut the top half off the tank so it is an open tank. We are just making use of the original burner. We could probably do the same thing with
fancy controls on a Turkey fryer, adding a 15-20 gallon
pot on top.

bill_71

ahhhh, i understand what you are doing now, well i guess the mixing valve idea is out of the question as well..

jp_2

use a flow valve

once the tank is up to temp, adjust the flame down like a pot on the stove.

i'd put a ball valve in series with the gas valve.