What Extras Do I Need To Fit To New Vented System Cylinders?

[Norcon]

Read this post CCC....
http://www.screwfix.com/community/message/253836#253836

This was before sf lost its credibility and had reasonable posters.
Pay attention to Doitalls information and also Moss.

 

[Boilerman2]

Why do people think Vented systems are History??? the number of Installs I have been to with either a Combi or a Unvented Cylinder connected to an incomming supply at less than 1 bar, and a flow rate of 8L/min!!! with a householder who want to do unimagineable things to the installer who has (suprise-suprise) gone AWOL

Vented systems do still have a place in the modern world and a one size fits all menatallity is often foolhardy!

THe customers for whom I have refitted Roof tanks and vented systems (above) pay testoment to this!

 

[Norcon]

Bangasman has a hang up about them. Thinks bacteria will poison him.

 

[Boilerman2]

Just as likely to find Legionella in a sealed system!!

 

[CareerChangeChancer]

Read this post CCC....
http://www.screwfix.com/community/message/253836#253836

This was before sf lost its credibility and had reasonable posters.
Pay attention to Doitalls information and also Moss.

Thanks Norcon. Very useful. Not sure that I understood all of Moss's post though! Seems like valve on cyl. return not needed.

 

[ironman1]

I will ignore the others with the holier-than-thou rantings.
.

When you're as qualified as the 'holier than thou guys ' you may have some clout , until then............................

 

[ironman1]

Seems like valve on cyl. return not needed.

Unbelievable ...................why i bother with the cost of lockshield valve along with time to install is beyond me , you have a good day & refer to this post when you have a bit more experience. ................if you can give me a reason why not to install one then i'm all ears............

 

[Norcon]

if you can give me a reason why not to install one then i'm all ears............

To allow the quickest possible heat up time for the cylinder and to give the cylinder flow priority.

As Doitall states....

Valves are only used or needed for circuit balancing and isolation.

Restricting the return will reduce the flow in the primary circuit, allowing more flow for the heating circuit or the by-pass

 

[ironman1]

if you can give me a reason why not to install one then i'm all ears............

To allow the quickest possible heat up time for the cylinder and to give the cylinder flow priority.

As Doitall states....

Valves are only used or needed for circuit balancing and isolation.

]

Most systems are piped in 22mm , without a restriction to primary return central heating circuit will suffer 'short circuiting' when both heating & hot water are calling , most systems are fitted with 5 metre head pumps which just adds to the problem...............when installing two seperate boilers for hot water/heating then lockshield valve is not required , same deal when installing two seperate pumps for heating/hot water....................lockshield valve will help isolate part of system when 'snatching' system for pump/motorised replacement , DON'T TRY THIS AT HOME!! , also applies to the guys less experianced , seems to be quite a few keyboard jockeys on here that get their info from books & internet.

 

[Agile]

Another reason for the lockshield on the cylinder is to restrict the flow to give a suitable differential for a condensing boiler.

I wonder how many know what Fog Factor is?

Tony

 

[Norcon]

Most systems are piped in 22mm , without a restriction to primary return central heating circuit will suffer 'short circuiting' when both heating & hot water are calling ,

Thats part of the reason for not installing one.
Hot water priority!

Also with the ch and hw balanced against each other with a valve, on hw only you will now have impaired the flowrate through the coil slowing down recovery.
Restricting the flow to acheive a temp drop is basically as Moss states a "snapshot" in time and only works for a very short period for the benefit of cendensing.

 

[ironman1]

Most systems are piped in 22mm , without a restriction to primary return central heating circuit will suffer 'short circuiting' when both heating & hot water are calling ,

Thats part of the reason for not installing one.
Hot water priority!

Also with the ch and hw balanced against each other with a valve, on hw only you will now have impaired the flowrate through the coil slowing down recovery.
Restricting the flow to acheive a temp drop is basically as Moss states a "snapshot" in time and only works for a very short period for the benefit of cendensing.

, It's REAL world out there , i can GUARANTEE you will not balance a system that is fitted with a 5 metre head pump when hot water/heating is calling WITHOUT a lockshield fitted to primary return , most of these hot water cylinders required 12,000 btus for a recovery time of 20 minutes , useing the lockshield to restrict return water will not impair recovery time ..............now if you're fitting a 300 litre megaflow that requires a recovery time of 20 minutes that's around 40,000 btus plus , in this instance you would use TWO circulating pumps , one for hot water circuit & one for heating.

Feed me all the jargon you wish , it don't cut it for real world experiance.

 

[Norcon]

It's REAL world out there , i can GUARANTEE you will not balance a system that is fitted with a 5 metre head pump when hot water/heating is calling WITHOUT a lockshield fitted to primary return

That right its not balanced without the lockshield because its not necessary to have ch/hw balanced against each other and will only slow down recovery on hw only.
And two circulators are not necessary either on 300l megaflows.

Feed me all the jargon you wish

Trolls need feeding I know.

 

[ironman1]

It's REAL world out there , i can GUARANTEE you will not balance a system that is fitted with a 5 metre head pump when hot water/heating is calling WITHOUT a lockshield fitted to primary return

That right its not balanced without the lockshield because its not necessary to have ch/hw balanced between each other and will only slow down recovery on hw only.
And two circulators are not necessary either on 300l megaflows.

May not be necessary but a good installer would fit two circulators , that's the difference here. ...........i guess the eight years spent @ polytechnic taught me nothing , better throw away those advanced heating certificates.

No i'm not a troll , just saying how it is.

 

[bengasman]

I wonder how many know what Fog Factor is?
Tony

I don't, is that the official indication, or a "nickname"?