Lighting an outdoor space heater (bypassing thermocouple)

[Richard]

Wife & her cousin are having a brunch tomorrow, at his house which is next door. He's got one of those 7 foot tall space heaters that has a big "hat" on it with propane at the bottom.

We got the propane replaced, got the pilot KIND OF lit..... it would light as long as we held the button in. Let go of button, pilot dies. I'm wondering if the thermocouple would be the next thing to look at.... and... is it possible to hotwire it? The thermocouple has two wires coming out of it. One goes to the side...a bit of a 'control panel' (hard to see as you see it on edge so don't get good look at it) The OTHER wire goes into a fitting that I'm guessing is where the main gas is ultimately piped through.

Party is tomorrow at 1:00. I'm doubtful if I can stroll into Lowes or HD and find a replacement (but don't know that). So I'm wondering is there some way I can disconnect something or short something to bypass it for tomorrow and deal with fixing it later.... OR, is it 100% dead in the water until the thermocouple is replaced? (I'm presuming it's the culpret and admit I don't know so right now I'm hoping with fingers crossed that it's a lucky guess)

 

[grsthegreat]

No, you cant bypass thermocouples. There there to prevent explosion.

 

[David Wayne]

Sometimes you can clean the thermal coupler with some fine emery cloth, also make sure the ground wire is acually attached and not just resting against the side.

 

[Chanceywd]

Along with the suggested cleaning, some gas valves have a screw marked pilot adjust. Sometimes you have to Remove a screw that will have a gasket or oring will expose a slotted screw that allows you to adjust the pilot flame. I just checked the one on my empire wall heater and it just has a labeled screw no cover screw. Sometimes turning it up a little will make the difference of it making enough millivolts to hold the gas valve open. normally near the tube that feeds the pilot flame. If that doesn't work I would suggest new thermocouple.

 

[Richard]

I'm fine with buying a new thermocouple.... (other than may not have time before 1:00 tomorrow)

That said... are these generally available at box stores?
Don't know how to describe this other than it's one of those tall skinny things with the flames up high and some kind of "hat" that probably helps radiate the heat outward and downward.

I've never seen one in use, I was asked to see if I could get it going and so far, we got the pilot to show a flame but the instant you let go of the plunger button (to feed the pilot) the 1" flame drops to a little tiny bud of a flame. If you immediately push the button back in you might catch it and bring the flame back.....otherwise it simply dies.

Also the striker/spark thing doesn't work but I'm not worried about that as he's got a 12" lighter.

Truth be told, I'm doubting this will be done in time for the party tomorrow. Tis ok with me, I just enjoyed the challenge to see if I/we could get it going.

There there to prevent explosion.

Explosions are SOoooo yesterday.....

I was expecting that a bad coupling would stop us in our tracks (but this isn't my expertise so I don't really know that it's the thermocoupling)

 

[grsthegreat]

No joke about explosion. Bypass thermocouple, gas flows. If heater ignition fails or shuts down, gas keeps flowing.

 

[JasperFrank]

OR

There is no easy way to "bypass" the thermocouple.

 

[Chewwy]

You could also try cleaning the gas flow paths with compressed air. We’ve had similar problems with our propane gas logs. Pilot light did exact same thing. Would stay lit only when the button was pressed. Solution has always been cleaning the propane flow path. Apparently, the flow path to the pilot light get partially blocked. Pilot light should also be blue, not yellow.

 

[rangerfredbob]

If it stays lit when you keep the button pressed it kinda sounds like a thermocouple. I'd known about thermocouples and how they work through engineering school but didn't realize those were actually thermocouple's... Turns out those valves work by using the electricity generated by the dissimilar metal temperature to hold an electromagnet on the fuel valve and let fuel flow, if the fire goes out the voltage goes away and the magnet lets go and shuts off the gas... simple...

You might be able to find the thermocouple at a stove store or BBQ store or something, but maybe not in a box store... there's a few different kinds so it's not just one...

You can test the thermocouple with a volt meter and a lighter though, unhook the side at the valve, put a volt meter across the copper outer liner and the tip that goes into the valve set on DC Volts (it's less than a volt...) then use a lighter or torch on the tip, anything close to .1V is fine, if it's unsteady and falls below say .03V with steady heat it's bad...

 

[lpakiz]

I have an LB White heater that occasionally has the pilot jet corrode up a bit and not provide a hot enough flame to energize the pilot system.
You can fool the pilot a bit by using a propane torch to add more heat on the "bulb." Then let go of the button and see if the pilot will stay lit.