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continue our conversation.What is the brand and model of your furnace? What is the water level in the sight glass?
Getting the circ to run is one thing. Getting the burner to fire up is another. Try this, jump the T terminals on the relay and tell me if the pump runs. If it doesn't and you have power to the pump then you have a bad pump. If you have no power to the pump but you have power to the relay then you have a bad relay. Getting the boiler to fire up is another issue. To do that try jumping the leads where the thermostat connects to the boiler.
So you have electronic ignition and you hear a ticking noise from the pilot burner (electrode)?
If the ticking continues then either the pilot didn't light or the flame sensor (electrode doubles as a flame sensor) isn't detecting the pilot flame. You need to be sure there's no pilot flame. If you can't see it now you need to remove the flame shield above the burners to check. This is a little dicey on the off chance the unit finally responds as it should and the main burners fire up. You could get some roll out of the main burner flame. Not likely but some thing to be aware of an to be prepared for by making sure no wiring has sagged that low near the burners and know just where the service switch is so you can kill the power quickly if necessary.
Ok, so you need to determine if you have 24 VAC to PV & MV/PV on the gas valve while the pilot electrode is ticking. If you don't go back to the same terminals on the ignition control and check there. If you don't have 24 v at the valve but you do at the control then the leads are suspect. If you don't have it at the control then the control is suspect. If you do have 24 v at the valve then disconnect/loosen the tubing to the pilot burner and see if you have any gas there. If you do then the pilot burner orifice is clogged if you don't then the gas valve is suspect.
The pilot burner is usually just bolted (small machine screws) to a bracket on the burner. Probably easiest to just remove the burner tube it's attached to. The burner tube should just slide off the orifice on the manifold (it may have a small U shaped clip holding it in place). Once you have it out disconnect the tubing at the base of the pilot burner. The orifice is a small thimble shaped object. It may come out on the end of the tubing or it may stay in the pilot assembly. It has a very small hole (~0.01") that you have to pass a fine wire through to clean it out. You need to do this even if you can see daylight through the hole. Take care to not enlarge the hole.