combi boiler, pressure continuously increasing.

[Juman islam]

Hi,

I have a vaillant ecotec plus 837 and one day noticed the pressure was maxed out therefore bled the radiators to drop it down to 1.2~1.4 bar.

Two weeks later, I noticed my pressure increased back up 2.5 bar so had to bleed the radiators again.

A guy at work told me the increase in pressure is probably is due a failure in my filling loop. What are other peoples views on why this is happening?

Thanks in advance.

 

[Aire]

If it's continually increasing even when the heating isn't been used then yes you may have a faulty filling loop/link. There are other possible causes for this too though so maybe best that you get a registered engineer in to check the system over.

 

[Rob Foster]

Turn off the filling loop at both ends and remove it carefully. If it leaks from the valve..s then call a plumber to replace the naughty valve. If the pressure still rises with the filling loop detached your problem is MUCH bigger and call a GSR combi specialist. Centralheatking

 

[JohnnyM]

As above with the filling loop but could be the **deleted as mentioning internal component** Call a Gas Safe Engineer.

 

[Coby kenny AGUILAR]

I think that model the filling loop is practically internal, built into controls (keeping it vague).

If you have no wet work experience call an engineer

 

[Juman islam]

Thanks lads. Got home to check the pressure and it was at 2.3 so increased again within a space of 2 weeks from 1.2.

I've attached a picture of my where my filling loop is. Mate at work said to get the boiler serviced abit earlier than usual and get them to replace the filling loop at the same time. Is the filling loop replacement an easy DIY or best to leave to the pros? Im quite good when it comes to DIY and mechanics but never worked in boilers before.

 

[Riley]

No pic

 

[Juman islam]

Sorry! Pic attached now.

 

[Rob Foster]

Thanks lads. Got home to check the pressure and it was at 2.3 so increased again within a space of 2 weeks from 1.2.

I've attached a picture of my where my filling loop is. Mate at work said to get the boiler serviced abit earlier than usual and get them to replace the filling loop at the same time. Is the filling loop replacement an easy DIY or best to leave to the pros? Im quite good when it comes to DIY and mechanics but never worked in boilers before.

It will not be the filling loop it might be the isolation valves, or something much more internal which requires a GSR fitter. Those
iso valves look rather tasty and expensive to replace. So take one end of the loop off with them turned off see if water still flows before replacing. centralheatking

 

[Aire]

Remove the hose marked in red and see if the valve is passing any water. If it is then remove the valve head marked in blue and see if you can nip the valve a little tighter with a spanner.

 

[Aire]

It will not be the filling loop it might be the isolation valves, or something much more internal which requires a GSR fitter

How can you say it won't be the filling loop when that's the first thing any engineer would check?

 

[Rob Foster]

How can you say it won't be the filling loop when that's the first thing any engineer would check?

the filling loop is just a connection, its the valves that might be passing chking

 

[Juman islam]

Remove the hose marked in red and see if the valve is passing any water. If it is then remove the valve head marked in blue and see if you can nip the valve a little tighter with a spanner.

View attachment 38188

So after removing the hose marked in red, if there is not water leaking past the valve, does that mean the braided loop only needs changing?

 

[Rob Foster]

So after removing the hose marked in red, if there is not water leaking past the valve, does that mean the braided loop only needs changing?

no the braided hose is just a connection its the integrity of the valves you are testing
chking

 

[Aire]

the filling loop is just a connection, its the valves that might be passing chking

My apologies, I see what your saying, when I refer to the filling loop I mean it as the hose and valves combined.

 

[Juman islam]

My apologies, I see what your saying, when I refer to the filling loop I mean it as the hose and valves combined.

I was thinking of getting the filling loop and valves changed first and was told to get a replacement, I need my GC number which is 47-044-33. Does anyone know where I can pick one up?

 

[Aire]

So after removing the hose marked in red, if there is not water leaking past the valve, does that mean the braided loop only needs changing?

After removing the hose, if there is no water, then the fault won't be with the cold inlet valve to the boiler, in that case you will need an engineer in to check the boiler over.
If it is passing water then it may just be the plastic head not shutting off fully, so by removing the plastic head and using a spanner on the brass nut, you may be able to close it off a little further.

 

[Aire]

If it is passing and your happy changing the valve then this is what you'll need
Heating Spare Parts

 

[Juman islam]

If it is passing and your happy changing the valve then this is what you'll need
Heating Spare Parts

And by changing this, is it advised to change the loop itself or is that fine to re-use?

 

[Rob Foster]

And by changing this, is it advised to change the loop itself or is that fine to re-use?

you obviously really want a new filling loop regardless that you dont need one. centralheatking

 

[Aire]

The hose itself should be fine but if you want to replace it all then you'll need this
Heating Spare Parts
And this
Heating Spare Parts

 

[Rob Foster]

let us know how you get on
centralheatking

 

[Aire]

Check The valve first though, no need replacing parts that are fine just because someone has advised you do it.

 

[Rob Foster]

Check The valve first though, no need replacing parts that are fine just because someone has advised you do it.

especially 'someone at work'

 

[Chuck]

Mate at work said to get the boiler serviced abit earlier than usual

Good advice.

get them to replace the filling loop at the same time.

Bad advice. The root cause is unlikely to be the 'filling loop' because that would require both valves to be passing, which is improbable. It can be eliminated as a possibility by disconnecting the flexible hose, which is how the system should be normally left in any case.

Im quite good when it comes to DIY and mechanics but never worked in boilers before.

And if you've got any sense you won't start now. Anyone who wants to 'work on boilers' needs to get properly assessed, qualified and onto the Gas Safe Register, go on the manufacturers' training course(s), then buy the several thousand pounds worth of gear needed to do the job properly and safely.

 

[johnduffell]

Try turning off the cold feed for a while and turning on a hot tap to release the pressure. Could simply be **an internal component related to hot water costing around 150 pounds** although you need someone to fit it.
*Edited to not name the component just in case

 

[Ready Steady Gas]

If you find the filling loop/valve to be ok, There is a test you can carry out to confirm whether it is an internal part that has a pinhole between the CH and MCW.

1. Turn off call for heat on programmer while testing.

2. Drop system pressure back down to 1.5bar .

3. Isolate CH flow and return valves and hot water outlet valve.

4. Leave for a day and see if the pressure has still risen.

If the answer is yes you will need a registered engineer to change the affected part.