Expansion vessel in Gravity feed system-Advice needed please

Joined
1 Jan 2013
Messages
63
Reaction score
1
Country
United Kingdom
Hi all,

I just need some advice in the following topic – expansion vessel.

My house is plumbed using a gravity system (with the usual water tank in the attic and water). Talking to my usual plumber the other guy who suggested to perhaps put a expansion vessel in the attic replacing the existing (small) cold water tank. He thinks that could help the radiator give better output and improve the efficiency of the central heating system.

What are your thoughts in the above topic?

Thanks in advance for the replies and Merry Xmas. :)
 
Sponsored Links
Joined
18 May 2009
Messages
175
Reaction score
1
Location
Durham
Country
United Kingdom
Why does he think it will? What are his reasons? The size of tank will not affect the pressure in the system unless the water level is increased, then you may as well just lift the small tank higher.

It is a common misconception the bigger the loft tank the greater the pressure in the system below. Same water level.... same pressure... simplz.

PS.. mine is the same type of system.
 
Joined
24 Jul 2003
Messages
24,298
Reaction score
1,416
Location
London
Country
United Kingdom
The tank you've got in the attic now IS an expansion tank.
Sure he didn't say Expansion VESSEL? That would mean he wanted to pressurise the system. That can make a small difference, but not much, it just helps get air out quicker really - so if you had a (bad) system generating a lot of air then maybe ....

First thing you should do is "balance" your system.
 
Joined
1 Jan 2013
Messages
63
Reaction score
1
Country
United Kingdom
The tank you've got in the attic now IS an expansion tank.
Sure he didn't say Expansion VESSEL? That would mean he wanted to pressurise the system. That can make a small difference, but not much, it just helps get air out quicker really - so if you had a (bad) system generating a lot of air then maybe ....

First thing you should do is "balance" your system.
Yes yes he said an expansion vessel. Sorry I actually confused the names.
The system gets a fair bit of air so I wonder if it is worthy to spend the many in the expansion vessel.

He did balance the system for me already.
 
Joined
17 May 2008
Messages
8,417
Reaction score
1,129
Country
United Kingdom
How much air?
Are you bleeding every day? Or once a year say?
 
Sponsored Links
Joined
1 Jan 2013
Messages
63
Reaction score
1
Country
United Kingdom
How much air?
Are you bleeding every day? Or once a year say?
I used to bleed daily and then turned out I had a leak in system. Plumber put some leak sealer and since then it has seemed OK. I haven't had to bleed any radiator yet.

How often would you call it "time to fit a vessel"?

I have noticed two neighbours in my street seem to have one fitted so there is a chance the cowboy builders did a quick job in these houses.
 
Joined
24 Jul 2003
Messages
24,298
Reaction score
1,416
Location
London
Country
United Kingdom
Sort out the "leak" first. Could be corroding, which causes accumulation of corrosion gases. Sludge, etc etc....
Old system, mix of a couple of "issues"...
 
Joined
1 Jan 2013
Messages
63
Reaction score
1
Country
United Kingdom
In a different note. I have zone the water from the heating. The only thing is that when heating the radiators, boiler only heats the water in the cylinder.

In my system, is there a way to heat radiators without heating the water in the cylinder?

Thanks,
David
 
Joined
19 Nov 2014
Messages
394
Reaction score
9
Location
London
Country
United Kingdom
Is it pumping over? If so then a One pipe feed and expansion tank may be the answer. A one pipe, 22mm, leaves the bottom of the tank. The boiler needs a high limit thermostat on the boiler. It is best to put an ant-circulation loop in the feed/expansion pipe. The circulation moves water oxygenated water from the tank to the main body of the system, meaning the water does not mix. This reduces the speed the water is being oxygenated, or maybe eliminate it.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Top