Combi Boiler with tvr's

[Keithbutler]

Hi,
Just joined the forum, I am a semi retired builder also am a time served plumber/heating engineer, I have recently moved into a property which has tvrs on all radiators, I have had a Valiant condensing combi boiler fitted, would this boiler have a built in bypass on it or should I have one of the rads without a tvr?

 

[oz-plumber]

Most boilers do have built-in bypass valves, but generally it is good to have an external bypass or a radiator without tvr's installed.
If you have a heated towel rail or a rad in bathroom remove the tvr and install manual valve or another lockshield.
We never usually install control valves on towel rails for this reason

 

[Reidy12]

You should really have two lock shield valves fitted on the rad near the room stat. Position

 

[Gas]

You should really have two lock shield valves fitted on the rad near the room stat. Position

One is quite alright, as per Approved Document L1

EDIT: Yes you are of course right, i misread and though you said on two different rads!

 

[Gas]

Most boilers do have built-in bypass valves..

I requirement since the end of 2006 i believe.

 

[Chalked]

Vaillant boilers have an internal bypass.

 

[gassafe]

Vaillant boilers have an internal bypass.

I would rather a bypass radiator with proper pipework than an internal piece of 6mm built in bypass... How much heat can that dissipate I wonder...

 

[Ermintrude]

Ideal suggest 10% of boiler ch capacity. I do it on every boiler.

 

[Centralheatking]

All the new boilers must have an built in by pass BUT the real question is
if the internal by-pass is as poor as the diverter valve would you trust it ? - CHK no way
so as above use the bathroom rad/towel rad as the bypass at least you know it will work

centralheatking

I requirement since the end of 2006 i believe.

 

[lame plumber]

£20 on an auto bypass ensures all is well and no one can fiddle with it.

 

[jase158]

new conventional boilers don't have a bypass do they? or system boilers? only combi's aint it?

 

[AWheating]

bypass on the system, be it auto (recommended) and/or radiator. When you have a new boiler you should also have a room stat so this room will not need a trv, problem solved.

 

[Ermintrude]

new conventional boilers don't have a bypass do they? or system boilers? only combi's aint it?

Heat only and system boilers require external bypass.

Gravity hw acts as bypass on partial pumped systems.

On fully pumped y plan normally a 15mm gate valve

On cascades or larger domestic normally find auto bypass set at defined pressure. (And some of the better installer s plan installs)