Glow Worm Ultimate boiler firing up but no CH or HW

[amarh]

Could anyone offer any advice on the following problem.

I have a glow worm ultimate boiler with a landys & gyr timing control unit for both CH and HW (options for on, off, once, twice). Recently the central heating and HW stopped working. The boiler fires up fine, the flame is visible and everything sounds the same however neither the radiators or the HW are heating up. The thermostat seems to work fine as it fires the boiler up when CH is on and the temp is above about 15C.
A corgi registered engineer came round and couldn't figure out what was wrong, he eventually suggested the 3-way actuator valve may be faulty. I replaced the Landis & Gyr actuator valve with a Siemens CMV322 22mm 3-Port valve that was advertised as an equivalent part however the problem is still there. I have tried running the CH and HW individually without any success.
Would appreciate any help on this

Regards
Amar

 

[stardanny]

Have you done anything before it stopped working?

How long do boiler fire up and then shut down?

Did you check the pump is working?

Dan.

 

[amarh]

Hi

No nothing at all. One night just noticed one night the CH wasn't working even though thermostat had been set to 20c all night. Then realised water wasn't heating either. The boiler will stay on as long as either the CH or HW is turned on at the timing switch or via thermostat

Amar

 

[Armo74]

As said above sounds like the pump isn't circulating.

 

[Agile]

A corgi registered engineer came round and couldn't figure out what was wrong, he eventually suggested the 3-way actuator valve may be faulty. I replaced the Landis & Gyr actuator valve with a Siemens CMV322 22mm 3-Port valve that was advertised as an equivalent part

Regards
Amar

He came round but was not sure what was wrong and suggested the valve?

Did he charge you for coming?

Tony

 

[xr4x4]

What pipes get hot?

 

[amarh]

Reply to Agile

He couldn't figure out was was wrong initially and after looking at the whole system he was fairly confident it was the valve. Luckily he didn't charge anything.


Reply to xr4x4

I've checked all the radiator pipes and none are hot however when the backup immersion heater going to the cylinder is switched on, the pipe coming out of the tope of the tank gets hot.

Reply to Armo74

The pump just before the actuator valve actually sounds fine, when the setting is increased to 3 you can slightly hear the increase in flow rate and can fell the slight vibration indicating it is working. How could I test the pump to check it is operational?

Thanks to everyone for contributing

 

[gaswizzard]

Reply to Agile

He couldn't figure out was was wrong initially and after looking at the whole system he was fairly confident it was the valve. Luckily he didn't charge anything.

Unlucky for you that you have spent money on a valve that wasn't needed , if you had paid the guy to fit a new valve then you wouldn't be out of pocket. , you must of had every confidence in him to of taken on board what he said.

How many more parts are you going to waste your money on?

 

[Armo74]

Look at the FAQ's in the Wiki plumbing and heating section that will tell you how to check your pump is working.

 

[xr4x4]

Ok, I'll put it another way, what pipes from the boiler and in the airing cupboard etc..get hot?

If the boiler is firing, something must be getting hot.

 

[amarh]

Reply to Armo74

I've checked the red Grunfos pump and it seems fine. There is a slight vibration from the unit when running, I took the screw on the face out, and there wasn't a slot but a square head into which a screwdriver could fit and it seemed that this was conected to the spindles which seemed to turn fine. There was a slight trickle of water coming out that was completely clean.
Checked the 3 settings on the motor and these seemed fine, i,e the flow rate seemed consistent with whatever setting it was put on.

Reply to xr4x4
After switching on the CH and HW for about 15mins, neither of the 2 main pipes connected to the top of the boiler are warm/hot, no radiators are warm, in the airing cupboard where we have been using the backup immersion heater, there were 2 pipes that were warm, one coming out of the cylinder with a red stop tap and goes up into the attic. Another pipe which comes up from downstairs, up into the attic but also goes into the top of the cylinder. This actually seemed warmer after about 15mins.
No other pipes were warm, not before or after the pump, neither of the 2 pipes that go into the base of the cylinder and neither or any of the pipes connected to the actuator.

Re the 2 pipes coming into or going out from above the boiler, shouldn't at least one of these be heating up?

 

[Agile]

The boiler fires up fine, the flame is visible and everything sounds the same however neither the radiators or the HW are heating up.

Regards
Amar

Right, although you say the flame is visible, I suspect that its NOT the full flame but the small first stage flame.

That implies to me that there is a fault in the boiler which will need a gas reg engineer to fix for you.

If it had been burning as you thought then that heat would have been going somewhere and something woud have been getting hot.