Potterton 10 – 16 Netaheat - not enough heat

[Spruce]

Hi, hope somebody can help with my boiler problem.

Called a Corgi engineer to service the gas fire and my Potterton 10 – 16 Netaheat Electronic (serial number GUK127942).
The reason for calling the engineer is that the radiators take more than one hour to become reasonably hot – they are never too hot to touch even if the heating has been running for ten hours, as a result the house can take 2 to 3 hours to become reasonably warm.

The engineer found that the pressure taken from somewhere on the gas valve could not be adjusted above 8 bar – but could be turned down to 6 bar. The burner and data sheet inside the boiler electrics cover states the max pressure should be adjustable up to 12.3 bar.

The engineer took a pressure reading of 21 bar at the main gas feed.

Looking at some other threads - mention has been made of the boiler control circuit board ( type 407676 serial number M136515) and the voltages for the gas valve, which are:
T1 – 225 V
T2 – 150 V
T3 – 0 V

The engineer informed me that he would need to find out some more information and would return at a later date – that was four weeks ago.

Could anybody throw any light on the problem before I spend more money on a different engineer.

All help greatly appreciated and many thanks in advance, Spruce.

 

[cozzmic]

Your gas pipe is either undersized or you have an obstruction between the meter and the boiler gas valve. Your pressure will be in millibars not bars and you should in a perfect world have a 1mbar drop between the meter and the appliance. Your engineer? should have picked this up straight away if he's worth his salt and could have advised you on how to rectify.

 

[Spruce]

Thanks for the reply Cosmic - my apologies for the late reply - been busy buying big coats.

I'll pass on your advice to the next engineer.

Incidentally, would a faulty gas valve have the same symptoms i.e. if it wasn't opening fully? Spruce

 

[cozzmic]

It is a possibility but I would go for the pipe work check first then maybe the gas valve. One other thing it could be crud from the gas pipe (can not remember the tech name for the stuff) caught in the filter in the gas valve, be aware that this would involve stripping the valve and only a dogs engineer could do this (corgi).