Vaillant Ecotec Pro 28 pressuring dropping - due to Magnaclean?

[wasilewski]

In January 2018 we had a new diverter valve fitted to our Vaillant Ecotec Pro 28 by an official Vaillant repairman.

After this we had a Magnaclean 2 fitted by our gas installer.

I had checked the water pressure on the Vaillant and it appeared to be OK, around 1.1 after the installer fitted the Magnaclean.

A few weeks after this it was noted the top of the radiator in the kitchen was colder than the bottom. This is the closest radiator to the boiler (if that makes any difference to any answers).

I bled the radiator and the air escaped along with about a teaspoon of water. I quickly tightened the valve and the radiator is working perfectly now.

I don't know what made me check, but I decided to see what the water pressure was on the boiler and it was 0.8, having dropped a few bars in a short space of time. I refilled it to around 1 - 1.1 and that was OK.

That was on Monday. Today I rechecked it and again it has dropped to 0.8! I have refilled it with a small amount of water.

I'm worried that the bleeding of the radiator has maybe done something. I checked for signs of leaks inside the hot press, which is where the boiler sits, but nothing. I have double checked the radiator valve is tight and sure enough it's tight.

Would anyone be able to give me some advice?

Many thanks!

 

[townfanjon]

What pressure does the boiler go up to after half hour or so ?

 

[wasilewski]

What pressure does the boiler go up to after half hour or so ?

After the heat has been on half an hour? Not sure, the heat has been on for a few hours so I can't check right now I'm afraid.

 

[townfanjon]

Sorry I meant after half hour or so , what is it now ?

 

[jtsplumbing]

Have you checked all your other radiators for air ?

 

[wasilewski]

Sorry I meant after half hour or so , what is it now ?

It's sitting at 2.2 now. The heat has been in for about 5 hours. I can give you a more accurate 30 minute reading tomorrow. Cheers.

Have you checked all your other radiators for air ?

I just checked them and they are all ok.

The chap who installed the Magnaclean did bleed all the radiators after he installed it a second I saw him. I did double check as per your advice though. Thanks.

 

[townfanjon]

It's sitting at 2.2 now. The heat has been in for about 5 hours. I can give you a more accurate 30 minute reading tomorrow. Cheers.

2.2 is too high if the pressure was approx 1 bar when it started , there maybe a problem in the boiler , which needs a gas safe installer to check .

 

[wasilewski]

Thanks @townfanjon. out of interest, what should the pressure be after 5 hours of having the heat on if the original pressure was 1?

 

[jtsplumbing]

Best to check when system is cold, needs to be around 1 to 1.5 will rise maybe 1 bar But its only a guide the gauge is not that precise

 

[townfanjon]

Thanks @townfanjon. out of interest, what should the pressure be after 5 hours of having the heat on if the original pressure was 1?

Pressure should be the same at 5 hours as it is after 30 mins , I shouldnt keep rising . In my opinion 2.2 is too high if its started off at 1 . Ask your installer to check the expansion vessel pressure . You wont know how to check it and shouldnt .

 

[wasilewski]

Pressure should be the same at 5 hours as it is after 30 mins , I shouldnt keep rising . In my opinion 2.2 is too high if its started off at 1 . Ask your installer to check the expansion vessel pressure . You wont know how to check it and shouldnt .

Thanks @townfanjon. There's no way I'd touch the boiler myself, the only thing I do is refill it and check the pressure.

What should the pressure rise by if it starts off at 1? Should it rise up to 2 or something like that?

 

[DevsAd]

On most well set up systems, the pressure should only increase marginally - say by 0.2 bar or so, although higher increases can be ok in certain circumstances ( I think like on larger rads systems, or multiple floors etc?).

But going from 1 bar to 2.2 bar seems hugely excessive for an average system.

Inside your boiler is a small tank called an expansion vessel. This has pressurised air on one side of a rubber membrane and the system water on the other - the idea is that the expanding water (as it heats up) is forced in to the 'water' side and squashes the membrane against the pressurised 'air' side, so the overall system pressure should remain pretty much constant.

When your system cools and the water contracts, it flows back out of the 'water' side, pushed by the 'air' side.

Chances are your exp vessel is not 'broken' but does need the 'air' side re-pressurised, a simple job for a plumber.

 

[townfanjon]

On most well set up systems, the pressure should only increase marginally - say by 0.2 bar or so, although higher increases can be ok in certain circumstances ( I think like on larger rads systems, or multiple floors etc?).

But going from 1 bar to 2.2 bar seems hugely excessive for an average system.

Inside your boiler is a small tank called an expansion vessel. This has pressurised air on one side of a rubber membrane and the system water on the other - the idea is that the expanding water (as it heats up) is forced in to the 'water' side and squashes the membrane against the pressurised 'air' side, so the overall system pressure should remain pretty much constant.

When your system cools and the water contracts, it flows back out of the 'water' side, pushed by the 'air' side.

Chances are your exp vessel is not 'broken' but does need the 'air' side re-pressurised, a simple job for a plumber.

Hold on pal , do not encourage people to go inside their boilers !!!!

 

[wasilewski]

Thanks guys. 🙂

 

[Scott_D]

How many radiatorsdo you have?

 

[wasilewski]

How many radiatorsdo you have?

11 and when the heat is on they are always on full.. Would that make a difference maybe?

 

[DevsAd]

Hold on pal , do not encourage people to go inside their boilers !!!!

I'm pretty sure I didn't.

Hang on - I am certain I didn't; I said it would be an easy job for a plumber.

Phew - would hate to think I'd put Wasi's life at risk with an informative post.

 

[townfanjon]

I'm pretty sure I didn't.

Hang on - I am certain I didn't; I said it would be an easy job for a plumber.

Phew - would hate to think I'd put Wasi's life at risk with an informative post.

Sorry with the greatest respect I disagree , I have been on here for years and you develop a sixth sence when people start fishing for information. Not saying the OP is doing that in this case , but whats to stop him ringing up his diy plumber mate who starts playing with the boiler ..... nothing .