Vokera Flowmatic 20 - 80 Not firing up

[YellowPeril748]

Had my shower this morning, turned it off, wife went to take shower a few minutes later and no hot water.

Went to check boiler and pilot light on but not fired up. I noticed the pressure was up to 3.5 Bar and as the 3 Bar had a red indicator by it, I wonder if the boiler had a failsafe device that had kicked in.

I sometimes have to top the pressure up, but wouldn't have taken it to this high pressure and can't explain why it was so.

Came home this afternoon and the pressure had dropped under 3 Bar but boiler still won't fire up - any suggestions please?

 

[45yearsagasman]

Firstly, does it fire for heating?

 

[YellowPeril748]

No it neither fires for heating or hot water

 

[DP]

Turn the gas control knob to off position and restart pilot after one minute. If no siccess, call an engineer. Your boiler most likely needs a proper service not a feather dusting.

 

[Agile]

Look at the FAQ on this site about the excessive pressure. It seems the expansion vessel may need attention.

The boiler does not monitor high system pressure.

Tony

 

[YellowPeril748]

I think I've sussed the extra pressure issue - my next door neighbour has been having some major plumbing work carried out and because we are a large house split into two, somehow we share some of the water system and if they change their pressure it affects us (we had trouble in the past).

I don't know if that would affect the pressure in our boiler, but I've backed our stop cock off a we bit.

However, last night the pressure dropped to 2.5 and I tried the boiler by turning the heating on and it kicked in, so I then turned the hot tap on and the heating off and the boiler carried on and the tap produced hot water. I then tried the tap on it's own and the boiler continued to work, and has continued to this morning.

 

[Agile]

Sounds like you have left your filling loop open !!!

 

[DP]

my next door neighbour has been having some major plumbing work carried out

Very much doubt that is the issue.

As for boiler working, you will be returning here soon as boiler working now is just a glitch.

 

[YellowPeril748]

my next door neighbour has been having some major plumbing work carried out

Very much doubt that is the issue.

As for boiler working, you will be returning here soon as boiler working now is just a glitch.

So what do you think the problem is?

over the past couple of years I've fitted a new Grundfos pump and new Vokera fan unit (which cured a few problems). The two micro switches that operate off the valves appear to be working - point me in a direction please.

 

[DP]

OP,

If you can take a shower and a few minutes later boiler supplies no hot water, one needs to check the boiler operation sequence to establish why it is not giving you hot water. To guide you remotely is difficult and to give enduser gas related guidance (not knowing their manual dexterity and having their knowledge of understanding) is frawned upon.

High pressure can be due to several issues. Is the filling loop disconnected? If not, why not as this is a requirement. See FAQ.

By the way, when you replaced the fan, did you replaced the fan gasket?

 

[YellowPeril748]

The filling loop has a tap either end and both of these are in the closed position.

When you say the fan gasket, do you mean the the gasket around the edge of the chamber cover, if so - yes.