Boiler Pressure

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At my Sherborne property is a vaillant 834 turbo boiler.

I had to top up the central heating.

On all of the videos on YouTube show I have to open/close 2 valves.
image.webp
The one on the very right of the photo is the water mains, I can open/close this one ok and the pressure picks up on the dial.

But the valve on the left of the ch water main seems to be stuck. To the open position.

The boiler is running fine and I have hot water/heating. I am just wondering if I can just leave it, or will I need to phone a heating engineer?

Ideas please...
 
If it needs to be closed for the correct running of your system then you should get it operational.

You can check/fix it your self if your able to get to it.

Can you take a close up of the valve in question so I/we can see the top? (it's hard to see in your photo)

Depending on the type of valve (Gate, Ball or needle) it may be calcified or rusted in position, what to do is to turn the system off and shut off the water feed from the city supply.

On some you can loosen the packing nut and this will help take the strain off the valve so you can turn it, however this will let water out of the system.

Once you loosen the packing nut (if it has one) you can tap on the valve body with a hammer (not very hard) this may break up the scale or rust to a point so you can turn the valve, if this does not work then you may have to call in someone to replace the valve.
 
These are all the photos I have at the moment.
image.webp image.webp image.webp
As had to come back to my Yeovil house, as I have some things I need to do. But I can get some more photos tomorrow, if needs be.
 
Yuck......Those types of valves are very hard to work on, you might try the tapping on it with the hammer (or whatever may fit) this may loosen up the crud that is causing it to stay open, but those are hard to fix.

And they need to be fitted by a pro as you have to take the whole thing apart to get them off.

Try squirting some WD40 into it, or what ever type of rust buster you have, this may loosen it up a bit.
 
Don't go messing with them Chris you will have a loop same as this for topping up chase the pipes back until you see something looking like this.
DSCN0472.webp
 
Don't go messing with them Chris you will have a loop same as this for topping up chase the pipes back until you see something looking like this.
View attachment 85576
That braided pipe goes up in to the boiler, and I am unable to see the other end. You can just see it in one of the photos. I will give it a squirt with wd40/ph crack it. If that works then great.

If not I will have to phone some one.

I guess the next question is:

Am I better paying for valiant to come out and fix it or should I get a local heating engineer?
 
Let the WD soak for about 15 min then try it.

As to the service, the factory guys know their stuff but cost more, the locals if they know that brand may be cheaper.

It's not in warranty is it? If it is the the factory guys may be the only choice.

And don't whack it too hard as the valve is a brass one, you could dent it.
 
The top up should be visible if its not a cowboy has installed it and you can expect all sorts of things wrong :(, like ive said don't mess with any valve in your pictures they are nothing to do with topping up/shouldn't be only old boilers had this, chase the pipes ive pictured pal.
 
That braided pipe goes up in to the boiler, and I am unable to see the other end. You can just see it in one of the photos. I will give it a squirt with wd40/ph crack it. If that works then great.

If not I will have to phone some one.

I guess the next question is:

Am I better paying for valiant to come out and fix it or should I get a local heating engineer?
I would have thought the top up was done on the last service. Maybe have a service and mention the valve. Either way you pay but it will probably be as dear to have a call to out as it is a service. I fitted a Valiant last year at home but I am not familiar with your model and mine is an open vent system.
 
I will have to phone some one. The boiler is shut off at the moment. Next time I go over there I will try and get it sorted.

Thanks guys for your help.
 
We had a Valliant ecotec pro28 installed when the council renovated the house, it worked great for about a month and after that it has done nothing but complain about low pressure
 
We had a Valliant ecotec pro28 installed when the council renovated the house, it worked great for about a month and after that it has done nothing but complain about low pressure
Then you have a leak somewhere. Probably small, possibly a packing gland on a radiator valve.
 
Then you have a leak somewhere. Probably small, possibly a packing gland on a radiator valve.
I've not noticed any leaks or water/signs of water anywhere, I'll have to take a closer look, I just presumed it was a crap boiler or installed by cowboys (installed safely though as it passed the gas inspection by another company)
When they installed it they ran all new plastic piping to the new radiators and before they left they knew there was a problem as they said to let the hot tap run slowly for a minute or 2 to get hot water (IMO with a brand fire new boiler, when you turn on the tap you get hot water within a couple of seconds not a minute or 2)
Council are more than useless and I'm waiting for them to come back out again to get it sorted or replaced
 
Rad pressure can vary quite a bit over time ...plus you get changes in pressure within the closed loop system as air leeches out and collects at the highest point ..(highest radiator)..
You should use a combination of air release (rad bleed) and fill loop top up ...until the correct and desired closed loop pressure is achieved and stable ..
This varies from boiler to boiler but usually in the region of 1.5 to 2 bar ..
Refer to manual for this value an set it as accurately as possible ..
So yes ..you do need a freely functional fill loop valve ..
If that is what you were referring to Chris..
?

If I have misunderstood then ..I appologise ..
Is it a combi boiler ?
If so I can't see why you would have to close the Hot/Cold tap water supply at the boiler during correct pressure setting in the closed loop system ..as this is isolated totally from the Central Heating..(except when using the fill loop)
??
rgds
VS
 
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Rad pressure can vary quite a bit over time ...plus you get changes in pressure within the closed loop system as air leeches out and collects at the highest point ..(highest radiator)..
You should use a combination of air release (rad bleed) and fill loop top up ...until the correct and desired closed loop pressure is achieved and stable ..
This varies from boiler to boiler but usually in the region of 1.5 to 2 bar ..
Refer to manual for this value an set it as accurately as possible ..
So yes ..you do need a freely functional fill loop valve ..
If that is what you were referring to Chris..
?

If I have misunderstood then ..I appologise ..
Is it a combi boiler ?
If so I can't see why you would have to close the Hot/Cold tap water supply at the boiler during correct pressure setting in the closed loop system ..as this is isolated totally from the Central Heating..(except when using the fill loop)
??
rgds
VS
Yes it is a combi boiler. It's a valiant 834 turbo. It was fitted by the council some 13 odd years ago. I bought the flat about 3 years a go.

And in that time it has only needed to be topped up twice. So I am told the boiler needs to be between 1.2 & 1.5 bar to work correctly.

All the you tube videos have 2 valves, I need to turn, to top up the pressure in the system.

I have identified the 2 valves the videos say, one on the left is stuck in the open position. And the one on the right is the one you open to top up the system.

When I try and move the valve with a screw driver the hole body moves, and the valve will not turn, I have tried in both directions.

So it looks like I will have to get some one to look at it.
 
Yes it is a combi boiler. It's a valiant 834 turbo. It was fitted by the council some 13 odd years ago. I bought the flat about 3 years a go.

And in that time it has only needed to be topped up twice. So I am told the boiler needs to be between 1.2 & 1.5 bar to work correctly.

All the you tube videos have 2 valves, I need to turn, to top up the pressure in the system.

I have identified the 2 valves the videos say, one on the left is stuck in the open position. And the one on the right is the one you open to top up the system.

When I try and move the valve with a screw driver the hole body moves, and the valve will not turn, I have tried in both directions.

So it looks like I will have to get some one to look at it.
Fair enough Chris ..tho I suspect it would work just fine using just the fill loop valve ..
I wouldn't worry that much if the pressure remained fixed once set correctly ..but I guess it wont hurt to get it replaced if it dont cost a fortune..
rgds
Evan
 
When they installed it they ran all new plastic piping to the new radiators and before they left they knew there was a problem as they said to let the hot tap run slowly for a minute or 2 to get hot water (IMO with a brand fire new boiler, when you turn on the tap you get hot water within a couple of seconds not a minute or 2)
Council are more than useless and I'm waiting for them to come back out again to get it sorted or replaced


With a combination boiler it's pretty much normal, to need to wait for a minute or two for the water to heat up coming through the tap.
 
Yes it is a combi boiler. It's a valiant 834 turbo. It was fitted by the council some 13 odd years ago. I bought the flat about 3 years a go.

And in that time it has only needed to be topped up twice. So I am told the boiler needs to be between 1.2 & 1.5 bar to work correctly.

All the you tube videos have 2 valves, I need to turn, to top up the pressure in the system.

I have identified the 2 valves the videos say, one on the left is stuck in the open position. And the one on the right is the one you open to top up the system.

When I try and move the valve with a screw driver the hole body moves, and the valve will not turn, I have tried in both directions.

So it looks like I will have to get some one to look at it.
I believe at 13 odd years its nearing the end of its life, especially for a combi as they take a hammering with a small heat exchanger.
 
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