Glowworm / Glow worm compact 80e locking out not working !!?

I have just had this exact problem after draining down the system to remove and refit some radiators.

Problem- On application of power the pump would run continually, and a demand for heat would result run the fan, not generate a spark, then fail to lockout. On removal of power there would be a burbling noise from the pipes.

Cause- Large pocket of air trapped in the top of the boiler system meaning that the pump cannot create a full pressure circuit and get the water moving. Because it cannot move the water it does not produce the pressure OK signal the unit is waiting on to prove the pump is good. This then prevents the ignitor starting and overheating the boiler.
Air pocket was let in when the system was drained and has not been removed by the Automatic Air Vent on top of the pump assembly.

Solution- Place a bowl under the pump motor, in front of the Red Pressure Safety Release valve. Add a bit of electrical tape to the front lower edge of the pump motor body to allow water to drip off the front not run along the underside.
DO NOT GET WATER ON THE ELECTRICAL BITS.
Using a coin, open the spindle valve cap on the pump motor by one turn. This will let some air out with some water dribbling down the pump motor and into the bowl.
AGAIN: DO NOT GET THE ELECTRICKERY WET: BAD FOR IT AND WORSE FOR YOU
Turn the unit on and more bubbles should escape. Turn the unit off and on when the bubbles stop until no more come out when it gets powered. Turn the timer to create a Central Heating demand and listen for more bubbles. Repeat if more bubbles are heard. The system should go quiet when all the air is out. Remember to keep the pressure correct with the fill loop as it falls.

This worked for me, and saved trying to replace the air release valve.
Please only undertake this if you are happy with both the plumbing and mains electrical side of things. If you drip water in the wrong place there is real risk of real death!
Good luck and hope this helps someone else avoid some cold showers. (did really focus the problem solving brain though)

Jaz
October 2016

My Glowworm Compact 80e has been great but for the passed few days we cannot get hot water to the bath! Everything else works fine heating, hot water to kitchen and bathroom sink but not bath? can anyone help?

Steve W
December 2010

It should have never been fitted by a CORGI registered installer as he should know better as it does not comply with current building regulations (not condensing) which came into force in April 2005!!!
Sounds like the diaphram on the pressure differential microswitch though.

The Manager
November 2008

Hi John

MANY THANKS, that's the boiler fixed, it was just a jammed pump !!!

Kalz
October 2008

Thanks John, will try over the weekend and will post the results.

Kalz
October 2008

possibly pump jammend remove centre screw on pump and rotate with scew driver best to take preasure out of system before doing this.

John
October 2008