What is wrong with a teledyne-Laars EG325 pool heater if the pilot light lights and the valve is on but the burner will not start up?

Answer 1

Here are a few things to check: Does the pilot light stay on after you light it? If so, good, did you turn the control valve to the "on" position? Sounds funny but there's a pilot position and a "on" position. Is the pump on? Water must be circulating through the heater to activate a pressure switch & then the burner will come on. If not find the manual on position for your pump timer to start the pump. Burner still doesn't come on? Check the burner assembly for plugged orifices (i.e. Spiders, corrosion, etc.)and clean it out.

The following is a more detailed and complete walk through, analysis :-

Swimming Pool Heaters have a number of safety controls. Before the heater will turn on, all the safety switched must be "Closed", that is to say the electrical circuit is complete.

But my heater doesn't have electric going to it you say ??

The Pilot light flame is directed towards a device that looks like an AA battery with 2 wires coming out the bottom. This is called a "Thermo-pile", ( from the French word "pile", meaning Battery.) This Thermo-pile creates electricity (DC, +/- 750 mV) which is the electricity that once it passes all the safety switches makes its way to the main gas valve and lifts the gas valve to Open and let the gas through to be ignited.

Some of the safety switches are :

Pressure switch. This is an important water pressure operated switch that tells the heater that there is water flowing through the heater. ( If your filter needs backwashing, and flow is poor -this switch will stay "Open" and not allow the heater to turn on.

On/Off Switch... If I need to explain this - stop reading and call a Gas Appliance Professional.

Thermostat : This is the rotary temperature Dial that senses the water temperature

Fusible Link. : Often mounted on the front inside of the Cabinet, just above the Heater tray, this switch senses if flames are coming out the front of the cabinet. -If the fusible Link blows (a) it needs to be replaced and (b) FIND OUT WHY!! Flames and heat should go straight up, if they are coming laterally out the front of the heater then the heater is not venting properly and you need to know why. Common causes are (i) on a heater with a Flat Top, and no Stack (Chimney), a gust of wind or a downdraft caused by winds bouncing off an adjacent structure or wall can cause the flames to roll out the front momentarily.

(ii) If the heater has been incorrectly installed with insufficient gas pressure, volume available to the Main valve, then incomplete combustion occurs, and the sooty smoke can clog the heat exchanger fins, which impedes the venting of the heater and the flames roll out the front.

"Tired " Thermo-Pile. The Thermo-Piles lose their ability to produce current over time, and the Thermo-Pile may be generating enough power to keep the pilot lit, but not enough to open the main valve.

There are other switches and safety's that vary on model and the installation, but the above information should solve 99% of problems.

Remember, we are dealing with a very minute current here. If any of the wire terminals are loose or corroded, that will reduce the efficiency of the electrical circuit and cause sufficient loss of power that the Main Gas valve will not open.

Good Luck

MaDoGreg

IF YOU HAVE TO LOOSEN OR OPEN ANY GAS CONNECTIONS, YOU MUST TEST THEM WITH SOAPY WATER AFTER RE-CONNECTION TO ENSURE THERE IS NO GAS LEAK. If in doubt, call a trained professional !

Greg M Simmons, C.P.O.

East Hampton, NY 1-631-831-5017 gregs.cpo@gmail.com