Ferroli Modena 80 E Boiler Pressure Gauge Faulty - Replace or Fix?

[wiggy11]

Hi,

I'm looking for help advice please.

The boiler pressure gauge was at zero, I tried re-filling/pressuring the system using the filling loop, but water started coming out the expansion vessel straight away. The vessel inner bag had burst!
Replaced expansion vessel which was already set to 1 bar, but boiler pressure gauge was still at zero
I slowly refilled/re-pressurised the system using the filling loop again, the pressure gauge didn't move, I stopped filling and the expansion vessel had gone over 2 bar, (checked with a basic pump pressure gauge).

So there's an issue with my boiler pressure gauge. It's a basic dial gauge. I could buy a replacement, but unsure what checks I can do to see if its something else.

The boiler still seems to work fine, radiators heat up fine, I just can't visually see the pressure.

Thanks

 

[ianmcd]

drain the boiler (dont rely on the guage saying it is drained obviously) disconnect the guage capillary tube from the hydro block, check the capillary and the port for blockages if they are clear put a tiny bit of water into the boiler via the filling loop and if the water comes out of the open port you need a new guage if it doesnt you have a blockage in the block

 

[wiggy11]

drain the boiler (dont rely on the guage saying it is drained obviously) disconnect the guage capillary tube from the hydro block, check the capillary and the port for blockages if they are clear put a tiny bit of water into the boiler via the filling loop and if the water comes out of the open port you need a new guage if it doesnt you have a blockage in the block

Thanks for this, yes will do.
If there's a blockage, what is best to remove this? Some kind of thin pin to poke in, or suck it out somehow?

 

[ianmcd]

Thanks for this, yes will do.
If there's a blockage, what is best to remove this? Some kind of thin pin to poke in, or suck it out somehow?

yes pin or small screwdriver, very common for there to be a blockage at that point, as the water never flows there, good idea if you clear a blockage to open the filling loop a little bit and flush out any crap that is still in there

 

[wiggy11]

yes pin or small screwdriver, very common for there to be a blockage at that point, as the water never flows there, good idea if you clear a blockage to open the filling loop a little bit and flush out any crap that is still in there

Great, OK will try this later on. Thanks again.

 

[ianmcd]

come back and let us know how you get on as it helps for others with a similar problem

 

[wiggy11]

OK, so I didn't empty the boiler, I thought I'd risk seeing how much water would come out once I disconnected the gauge capillary tube from where it was connected, I turned all water inlet/outlet valves closed before doing this. Only a small amount of water came out from where the gauge capillary tube port was connected, which was surprising.
There was slight build-up of black-ish stuff where the port had been connected, but not much.

I checked the capillary port end but the opening was a very narrow slit (by design) and could hardly poke anything into it, even a narrow needle couldn't really go into it much.

With the capillary port still disconnected, I turned the water valve going to this area enough for water to come out, then closed the valve again.

After connecting it all back as it was, the gauge still reads zero. I put heating back on to check it still works, radiators nice and warm still, no leaks anywhere that I can see.

It looks to me like the gauge must still be blocked or is faulty, at least it's easy to replace.


Does all the above look right from what I've tried to explain?

 

[ianmcd]

Yes you need to replace it , not expensive to buy and start saving for a new boiler

 

[wiggy11]

I've got one on order now, should arrive in a couple of days.
I'm hoping the boiler lasts a while longer yet, can't afford any big bills at the mo.

 

[wiggy11]

Gauge arrived today and is now fitted, working great