This website is always growing and changing as I get more pictures to help illustrate how to do specific maintenance and repairs. Some repairs are unique to specific boilers others are common and can apply to most boilers. For now we will start with this old Burnham boiler. This started as a no heat call. I determined that the thermocouple was bad. Normally I would just replace the thermocouple, relight the pilot, put the boiler back on, make sure all returns came back hot and then be on my way. But as it goes many times, there were other problems. What I am going to show you is why I did not just replace the thermocouple and go.
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You may notice the garbage can sitting on top of the boiler, and the fittings leaking water in to the garbage can. But what is important is where the water was dripping before the garbage can was put there.

This is the main gas control for this boiler From here on I will refer to it as the "gas valve" Take A good look at it, see the water stains, This gas valve is dangerous. Any gas valve that has been exposed to this much water MUST BE REPLACED.

Ok Now we Have Dielectric unions to repair, A bad Thermocouple To replace, A bad gas valve to replace, and this boiler is dirty. So As Always First things first. Turn Off the Power And The Gas To This Boiler.

After the door is removed, The bottom of the boiler jacket is not screwed in so it just lifts up and out of the way now with that out of the way we will pull the main burners. This is specific to this type of Burnham Boiler Only.


On both the left and right side of the boiler are little swing locks loosen the Philips screws and turn the locks out of the way and snug the screws so the tab stays out of the way.	Now we have to loosen the union and remove the nut from the lower section called the burner tray.	Now we need to remove the pilot tubing by taking apart the coupling. Now the tray is ready to slide out. (only with This type Of Burnham boiler)


The whole tray just slides out, The cast iron burners are secure to the tray	We need to remove the burner with the pilot assembly on it. So remove the screw on the top of the burner and the burner lifts up from the top. See pictures.	This pilot assembly was not installed properly (possible because the home owner did not know how to remove the burner tray. It is very hard to do with out removing the tray. Remove the pilot assembly I have decided to replace it.

With the tray out of the boiler vacuum all the burners and around the front of the boiler You can remove all the burners and wash them in a bucket or a sink. Note: Cast iron burners stay hot for a very long time.

Some pilot assemblies require the threaded adaptor that comes with the new thermocouple others do not, this one does, so I use it. It just pushes on to the thermocouple.

So I get a new pilot assembly out of my truck, i remove the pilot tubing from the old one and put it on the new one Make sure the little orifice does not fall out of the new pilot assembly. and make sure the pilot tubing compression nut is tight. It is easer to do this with the pilot assembly off the burner and with out the thermocouple in place. after it is tight it is time to install the new thermocouple.
Now I just screw it into the pilot assembly just snug is all that is needed, it is a fine thread and it can't be made tight, and does not need to be.

	When putting the burners back make sure the center of the back of the burner goes over the orifice nipple. and the front little pimple goes into the little dimple on the tray.
Now I attach it to the burner with the 2 screws. and the thermocouple is replaced.	If it is in correctly it will not move side ways. then put the screw back. now the tray and burners should feel like one piece the burners should no have any play in them at all. Make sure the pilot tube and the thermocouple are facing towards you. Now slide the tray back in.	Line the union up and make sure both tabs drop back in there slots on the left and right side of the tray. Now normally I would just say tighten up the union but we have to replace the gas valve first.

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