Pilot on but no heat to radiators

No this is not normal .The pilot should lite first then when you hold button down until thermocouple sense the flame and tell pilot to stay Lit .
I think you should change out the whole pilot assembly.
Does this pilot needed to be lit manually or has a sparker

Did you turn the control knob to heat from pilot setting? don-ohio

Are you letting the pilot flame heat up the thermocouple for one minute before you try to turn to ON? don-ohio

If your pilot light is lit, then you do have some gas flow, so it is probably the thermocoupler (the part heated by the pilot light) that is not telling the gas valve to open the main line. Sometimes it is just a case of residue on the thermocoupler that is not letting it get up to temperature and sometimes it has been knocked out of alignment and the pilot light is not putting direct heat on it.

A cleaning with steel wool (don't overdo it) would take care of the residue, and you can GENTLY move the thermocoupler back over the pilot flame. If neither of that helps then replace the thermocoupler.

Well, let's start the trouble shooting process with trying to get the pilot lit...
Have you removed the cover at the bottom of the heater?-- Can you see an pilot light inside?

If not, Can you try lighting the pilot-- and noticing how the pilot flam heats the little ThermoCouple (TC)?
Note: In order for gas to flow thru the main control valve, the pilot light has to be heating the TC-- to generate a voltage, that in turn allows the main gas valve to open.
Do you need help in getting the pilot light lit?-- do you understand the need to hold down the start button, until the TC gets heated up?

Let us know what you find

Mack B

It depends on what type of unit you have if it is gas or electric. If it is gas your pilot light is probably not lit .take the top door of your furnace off look under the burner and see if there is a small flame lit . if not it is simple to light turn the knob on the gas valve to pilot then push in on the know while holding a match at the pilot head to find the pilot head trace the small aluminuim pipe from the gas valve to where it ends that will be the pilot head once the pilot lights count to 10 slowly then switch the knob to the on position and your set make sure the t-stat is in the off position before lighting the pilot light.

If it is electric heat strips or a heat pump there is nothing to do other than turn t-stat to heat and make sure all 220 breakers are in the on position.

thermocouple any plumbing or heating shop juast ask for a universal thermocouple ie honeywell the heating shop willl know what you will need

Hi - hope someone can help. I have a VOKERA EXCEL 80SP combi boiler and been without hot water/central heating for two days. The pilot light is on, the fan is on, but boiler not triggering once the hot water tap is turned on.
Hopefully someone come to look at it today but hoping for some advice. Anyone else had this problem?
Thank you.

The pilot light has to be lit before gas valve will operate. That's a safety feature so the valve won't open and fill the garage with gas and possibly cause an explosion or fire. If you have a standing pilot and can't get pilot to stay lit, it's usually the thermocouple and it will need to be replaced. Once the pilot is lit, the gas valve comes on and heats the combustion chamber up to approx. 100° to 125° a thermostat controlled fan switch will close and bring the blower on.