Have a dayton hanging garage heater when trys to start acts like gas valve not opening heaters brand new.what should i look for

Does unit fan come on ??? Is flue clear as most units have a safety klixon if exhaust not venting properly.

Thermocouple/flame sensor error

Dayton is a Graingers Brand. Go to the site below and I'm sure you can find your part. Put in your Part Number...Jim


http://www.grainger.com/Grainger/rp_parts_home.jsp

No I do not believe it is your thermocouple, as that only detects heat from the pilot light and permits the gas valve to open and have main flame ignition. I would be looking at thermostat placement, and safety limits built in to the heater. Making sure that the thermostat is not getting a straight on blast of hot air from the heater is my first guess. Try jumping out the thermostat by first removing the thermostat from it's housing and placing a jumper between the red and white wires as they are usually the control for heat. If your heater stays running it is the thermostat. If not you now have to trouble shoot all safety limits one at a time with a volt ohm meter and run continuity tests the limits should read closed except for the fan high limit it should read open until the temperature of the heat exchanger reaches it's set temperature. Remember to power down your unit when trouble shooting please.

Hi blow heater out with air line flame sensor could be dirty check out pressure switch jump this out see if it lights

try cleaning the thermocouple or even replacing it because if the thermocoulple doens't sense the pilot light then it won't open the gas valve.

Hi,
Yes, it can be set on concrete blocks or anything non-flammable.
Also make sure that you do not run it if you are working with flammable gases or materials. I don't believe that that heater is sealed combustion.
Make sure also that you have correct venting so you don't wake up dead...
If you can take good precaution then go for it...

Heatman101

FOLLOW THE ALUMINUM 1/4 INCH TUBING WHICH IS THE PILOT TUBING WHERE IT ENDS IS WHERE U LITE

Hopefully there is a wiring diagram glued to one of the panels to verify but on the transformer you will have 2, 110 volt wires. One is the power coming in (usually black wire) and the other is a common (white wire) and will be connected to other common leads. On the low voltage side of the transformer one wire will go to the thermostat then from the thermostat to the gas valve. The other side will connect to the gas valve. When the thermostat calls for heat it completes the circuit from transformer to gas valve back to transformer.

not hard but before replacing check pilot light and thermocouple for proper function and setting if pilot light not in right position thermocouple wont open gas valve if electronic ignition check for power and proper gap on igniter also check stat for proper function