Boiler fires up but then goes off after a few mins.

[jackdoolan]

Hi i'm a newbie so please be gentle. I have an Ideal Classic RS40 boiler, a Randall 103 programmer and a Honeywell T6160 Thermostat. When I switch the Programmer onto constant the boiler fires up and then goes back to the pilot light after a few minutes. The boiler then won't re-ignite for at least an hour. When it does the same thing happens. Altering the thermostat doesn't make any difference. Could anybody suggest what to check or change? I've taken the covers off both the programmer and the thermostat and all wires are still connected.
Thanks in advance.

 

[ollski]

probably the pump is stuck or dead...take the screw out of the middle, be prepared for a small amount of water to come out and then see if you can turn the spindle to get things moving.

 

[croydoncorgi]

Pump jammed? system short of water?

 

[jackdoolan]

Thanks for the replies. Can you tell me where to find the pump? Sorry for the silly question but as I said I'm a newbie to plumbing!

 

[felix]

Unfortunately, the apparently simple question "Where's the pump?" has no easy answer! If the thing's turning you can listen for it. Why not try that anyway. You'll need to do it in an almost totally silent house.

The probability is that yours isn't doing anything so you'll just have to hunt it down. Popular places are above the boiler or in a cupboard with the hot cylinder. If you find nothing at either location, search along a line between them. You might find it lurking behind a removable access panel.

 

[jackdoolan]

Thanks Felix found it at the bottom of the cylinder cupboard. Checked it out and got it up and running. The heating then worked great with the radiators getting really hot. It ran for about 1/2 hour with the shutdown and re-ignite working when required temperature reached. But then it shut down and just won't re-ignite. When i felt the pump it is mad hot, is this normal? By the way the pump is a SMC Comet 2-130.

 

[kevplumb]

change the pump

 

[jackdoolan]

Cheers do you know the equivalent Grundfos model, because I got told they were the best?

 

[kevplumb]

15/50 i think

not very good with numbers tonight

 

[felix]

A pump gets as hot as the water inside it - and then a bit more. That much is normal. What did you do to get it going? Was it a stuck rotor? If it's stuck again it may need cleaning out. You'll have to take it out anyway so have a look. If the pump is jamming but not on sludge then it's a bin job. Go with Kevplumb (don't take that too literally) and get a new one.