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This is a garage heater isn't it?
OK, are you sure these units have a fan that comes on by lowering the thermostat?Most unit heaters just have a fan that comes on after burners ignite to circulate the heat
Normally the fans are only on when burners are lit.Tell me how many wires you have at thermostat . If only two wires, touch the wires together and see if we get any response.
1. Do you see a wiring diagram you can send me a pic of (I do not have manual on the model)
2. Do you have a volt meter so we can troubleshoot?
3. Did this model have a control board with a light to blink letting us know of a malfunction?
Lest make sure the limit shows continuity with wires removed.
Then with thermostat calling for heat check for 24v between 24v common and 24v Hot from thermostat.
I am here. Lets check to make sure the limit is closed with wires disconnected. If so turn thermostat to call for heat and let me know if we get 24v to the valve
Sorry for the delay.Got called away right after I replied. Can you bypass the fan switch to see if we get power to motor?
I mean close the circuit below to fan by bypassing fan switch to see if motor will run
OK lets do this.jump the wires at the thermostat together and see if we get 24v at gas valve.
How about 24 at the TR terminals on valve?
Hmm we may have a bad transformer. Don't these come directly from transformer? And how about 120 into transformer?
Let me know if the transformer fixes you up.
I see.So you have a new transformer but it has 120 in but nothing out?
I only see one transformer on diagram. Power comes into transformer. Thermostat calls for gas valve to open , burners come on ands once temp is reached limit to fan closes signaling fan on from what I can tell.
WE only need 24v output but this should be fine.Anywhere between 24 and 28 is acceptable.Is the transformer not sending 25v out?
TR and TR at valve 24V?
OK jumping the thermostat wires should make valve open.
24V common goes to one TR terminal. 24V hot goes to other TR terminal.
One thermostat wire should connect to each TH.
When thermostat is raised or jumped the circuit should flow back to TH at valve giving us 24v between TR and TH See below.
Gas valve should be clicking and opening. If not the solenoid on the valve may be defective
OK. Make sure gas supply is on also.
Appears it should be functional once you have gas. If the valve is clicking, that means it is opening.
I think if we get gas it will work. Here is what should happen. Thermostat calls for heat,gas valve opens, burners light and heat chamber,when warm blower is energized.