Join for free
Page 1 of 8 1 2 3 > Last »
AnnieS's Avatar
AnnieS
Chatterbox
AnnieS is offline
United Kingdom
Joined: Jan 2017
Posts: 18,420
AnnieS is female  AnnieS has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 03:35 AM
1

Sealed instead of vented heating system

So the boiler isn't working again. Every year this seems to happen.

We have a vented heating system which is causing all sorts of problems as the radiators aren't new and the system keeps filling with sludge. So the plumbers have suggested converting to a sealed system. Apparently this will fix everything, but I have heard that several times before. At one time the vented system was said to be the answer to all our prayers.

I was wondering if any of the resident DIY experts have any views on sealed systems. I've been told they can cause leaks because of the high pressure.
Dextrous63
Chatterbox
Dextrous63 is offline
Manchester, UK
Joined: Jan 2016
Posts: 7,727
Dextrous63 is male  Dextrous63 has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 04:56 AM
2

Re: Sealed instead of vented heating system

Originally Posted by AnnieS ->
I was wondering if any of the resident DIY experts have any views on sealed systems. I've been told they can cause leaks because of the high pressure.
The majority of the "sludge" is, in fact "rust" which comes from the radiators and not the copper pipes. This comes from the fact that oxygenated water is available from the expansion tank in the loft, although this is usually dealt with by adding an inhibitor (which is also added to sealed systems).

There are other ways that you can prevent excessive build up, including inserting a "Magnaclean" or equivalent, which is basically a magnet inside a container, which can be cleaned on a regular basis without the need to drain down the system.

As for a sealed system leading to leaks, it's possible but unlikely since copper joints are copper joints and should be able to withstand the increase in pressures involved.

Whatever the case, the system should be powerflushed (which is expensive), or have each radiator taken off and flushed through with water from a hose. If the plumbers are talking about replacing the boiler, then the system has to be cleaned out anyway since it is a requirement of the installation procedures anyway.

Personally, I'd not bother to replace the boiler unless necessary, but manually clean out the system in the way suggested and then add a system cleaner and magnaclean, let it run for a few weeks and then flush the system out again before refilling with inhibitor added to the expansion tank (top up once a year). This should last a good few years and prove just as effective as converting to a sealed system. IMHO, obviously
OldGreyFox's Avatar
OldGreyFox
Chatterbox
OldGreyFox is offline
South Yorkshire
Joined: Feb 2015
Posts: 21,202
OldGreyFox is male  OldGreyFox has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 10:15 AM
3

Re: Sealed instead of vented heating system

What type of boiler are you using Annie, and how old are your radiators?
Sweetie pie
Chatterbox
Sweetie pie is offline
Dorset
Joined: Oct 2016
Posts: 27,450
Sweetie pie is female  Sweetie pie has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 10:29 AM
4

Re: Sealed instead of vented heating system

We used to have the problems Annie, so changed to a combi. Still have problems with silt and yet another power flush soon.
We would need to know more about your system. I'm no expert, but I have had so many problems, I am nearly qualified.
galty's Avatar
galty
Chatterbox
galty is offline
rainham essex
Joined: Aug 2009
Posts: 6,080
galty is male  galty has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 06:34 PM
5

Re: Sealed instead of vented heating system

Originally Posted by Sweetie pie ->
We used to have the problems Annie, so changed to a combi. Still have problems with silt and yet another power flush soon.
We would need to know more about your system. I'm no expert, but I have had so many problems, I am nearly qualified.
Then as Dex suggested get a Magnaclean fitted.
fender's Avatar
fender
Chatterbox
fender is offline
SE England
Joined: Jan 2016
Posts: 6,286
fender is male  fender has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 06:49 PM
6

Re: Sealed instead of vented heating system

Much of what Dextrous says is correct. However, after flushing and fitting a magnaclean, you should not need to flush again.
And yes, add an inhibitor.

However, you've not explained properly. Is it that the boiler itself is not working, or the heating is not working due to sludge in the rads??

Some notes:

1. Don't get ripped off with a powerflush. They will give all sorts of bull to justify the cost, such as the cost of the equipment etc. Truth is, a decent one is around £700, but they use it all the time and they last years. All you should realistically be paying is a days labour, plus a bit of travel time / mileage, for a decent reverse flush to be carried out. Plus the cost of a decent inhibitor like Fernox.

2. If you have a combi system fitted, as Dextrous said, you'll need a powerflush as part of the works anyway.
The increase in pressure should have no effect. Another scare tactic to extract more money from the unknowing. Still have an inhibitor added to the closed loop heating circuit though.

3. If you go the route of a high efficiency condensing combi, you should find that your heating bill will drop quite a lot. You also gain space, as you will lose the hot water cylinder and both tanks in the loft.
fender's Avatar
fender
Chatterbox
fender is offline
SE England
Joined: Jan 2016
Posts: 6,286
fender is male  fender has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 08:03 PM
7

Re: Sealed instead of vented heating system

Another thing to check Annie.

When the system is running, feel the radiators.

Cold at the bottom and hot at the top = sludge in the rad.
Hot at the bottom and cold at the top = air in the system and the rads just need bleeding...
AnnieS's Avatar
AnnieS
Chatterbox
AnnieS is offline
United Kingdom
Joined: Jan 2017
Posts: 18,420
AnnieS is female  AnnieS has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 08:36 PM
8

Re: Sealed instead of vented heating system

Originally Posted by OldGreyFox ->
What type of boiler are you using Annie, and how old are your radiators?
It's a vailant (not combi) only 5 years since installation. Some of the radiators are decades old, I'm not really sure how many!
AnnieS's Avatar
AnnieS
Chatterbox
AnnieS is offline
United Kingdom
Joined: Jan 2017
Posts: 18,420
AnnieS is female  AnnieS has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 08:40 PM
9

Re: Sealed instead of vented heating system

Originally Posted by fender ->
Another thing to check Annie.

When the system is running, feel the radiators.

Cold at the bottom and hot at the top = sludge in the rad.
Hot at the bottom and cold at the top = air in the system and the rads just need bleeding...
Thanks I'm trying to remember what they were like when they were working. I think some would be cooler in the middle so maybe there's a bit lot of sludge there.

They said the powerflush will sort it and that the sealed system will get rid of the oxygen that causes the rust so fingers crossed. I'm so fed up with heating engineers scratching their head and tutting when they can't get it to work!
Dextrous63
Chatterbox
Dextrous63 is offline
Manchester, UK
Joined: Jan 2016
Posts: 7,727
Dextrous63 is male  Dextrous63 has posted at least 25 times and has been a member for 3 months or more 
 
18-09-2018, 08:43 PM
10

Re: Sealed instead of vented heating system

Originally Posted by fender ->
Much of what Dextrous says is correct. However, after flushing and fitting a magnaclean, you should not need to flush again.
Agreed. Just going for a bit of overkill
 
Page 1 of 8 1 2 3 > Last »

Thread Tools


© Copyright 2009, Over50sForum   Contact Us | Over 50s Forum! | Archive | Privacy Statement | Terms of Use | Top

Powered by vBulletin Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.