Thermal Store not heating?

Can someone shed some light on the following, please!!?

From time to time my central heating doesnt come on when asked to do so. The Gledhill unit appears to be cool and i think this is because the thermal store is not heating up.

This happens when the heating has not been on for a while (most common, first thing in the morning)

Weird thing is that when the thermostat is left on the heating eventually comes on, almost as if the thermal store has been 'heated' from a cold start!

This is driving me nuts as when my contractred engineer turns up, the radiators are piping hot and the hot water is working fine! They then cant find anything wrong. When checking Gledhill's 'super duper' fault finding circuit board it shows nothing untoward.

Whats the answer??

Just an update to this for anyone having similar problems. This has been diagnosed as a boiler fault (Ideal Classic Slimline FF) circuit board.

What happens is that the circuit board suffers from hot and then cold temperatures as the boiler is situated in the garage. Hot when the boiler fires and cold when not! This means that the solder joints are continually subjected to differing temperatures and eventually burst, thus leaving the connection pins on the board loose.

This has been the second board in the Ideal that has had to be replaced. I had this problem before and i though that changing the Boilermate circuit board worked. Apparently it has been the boiler - not the Boilermate - all along!

My faith - used loosely - has been restored in Gledhill, for now!

Hmm, I just posted on the 'temperamental switch on' thread but now reading this thread it looks like you may have answered my problem. Our Ideal boiler is also in the garage and the most common times our heating doesn't fire up is the morning. Think I'll maybe show your post to the engineer if/when he turns up. Thank you!

No worries. From reading your post (on the other topic) it appears this has happened at the same intervals as mine - Ideal board works for around 2 1/2 years then packs in!

A board costs around £97 so hopefully you have this covered and GW cough up and it only takes around 10 minutes to replace (if that)

To be absolutely sure that it is the store not heating, you can check the store temperatures by taking off the front panel and reading the digital display. One set of figures is what the factory settings are (what they should not go below) and the other is what your system is running at at the moment. You'll need to consult the manual for the 'factory' settings.

I know of someone else who has the same system but rather than the boiler being in the garage, theres is situated in the utility room (nice and warm and at a constant temp). They have had no issues with there system at all in 4 years, therefore it looks like the placement of the boiler being subject to differing temperatures is key.