Ideal Mexico not firing up

[pagey179]

I have an Ideal Mexico Super 2 RS70 B/F boiler which today stopped working.
The symptoms are:-
1. The thermostat does not 'click' when I turn it up and down.
2. The pilot is lit OK and the boiler fires up for a couple of minutes then shuts down again. Then fires up about five minutes later then shuts down again.

I suspected the thermostat (?) but have tried removing it and shorting out the wires - the boiler just does the same - fires up for a couple of minutes then shuts down.

Everything I'm reading says the pilot light would go out if the Thermocouple was knackered. Any ideas please......

 

[kevplumb]

pump

 

[Soggy_weetabix]

But do you have one?

Just spent an hour clearing air locks on a full gravity system. 2 Inch copper off the boiler! When was the last time you have seen that.

Cant believe it still exists!

David

 

[pagey179]

Not Pump - only a year old and working OK

 

[kevplumb]

what system do you have

have you checked the pump or are you assuming its ok

 

[pagey179]

Pumped central heating, gravity hot water - the pump is right next to the boiler and I can feel what seems to be it pumping in the pipes next to it - when the boiler does fire up the pipes become hot quite quickly but then, as I say it just shuts down again.

 

[kevplumb]

pump is stuck

 

[Agile]

Not Pump - only a year old and working OK

The age makes no difference to whether its working OK.

You need to see if there is power to the pump "when it shuts down".

If there is power then clearly the pump is faulty.

I have found a few that stop when they get hot !

Tony

 

[pagey179]

I've just been and taken the front off the pump (typical Grundfos type with 4 allen screws) switched the power on and got a lovely wet stripe up the wall - as I said the pump runs fine!

 

[Papion]

If it has an Air Pressure Switch, try blowing into it a few time to reset it. or it could be a certain sensor (switch) trip it off. Try asking for a servicing manual to troubleshoot it.

 

[kevplumb]

errr

I have an Ideal Mexico Super 2 RS70 B/F boiler

methinks no aps cos no fan

 

[ChrisRoberts]

Ball valve in exp is stuck or cold feed is blocked. there's no water in the system.
If it was the pump it'd still gravitate up the primary.



Always check the easy things 1st instead of looking for things that ain't there.

 

[kevplumb]

good point

 

[pagey179]

I'm sorry guys - I'm confused. I think this can only be something in the boiler. There is plenty of water in the system and even if it was totally dry what would stop it firing up in this design of boiler?

Were talking about a 18 year old boiler (designed 25 years ago) in its simplest form. Burner, water chamber, thermocouple (goes to the pilot light I believe?), thermostat marked 0-6 (with a sensor down a pocket on top of the boiler), gas valve and wiring in a plastic covered junction box. No fans, no PCB's, no inbuilt pumps, no controllers, no other sensors.

To clarify, there is water circulating in the system and the pump is OK. I probably should have said at the start because the boiler is still firing up every few minutes the radiators are warm (just), and the hot water can best be described as "not cold".

 

[namsag]

With everything calling for heat test the gas valve for voltage if boiler keeps turning on and off and voltage is constant . You have a faulty solenoid operator on the gas valve . Breaking down under use... If it was pump or little water in system as you have bridged out boiler stat boiler would still stay on and get extremley noisy.