Big house with 2 boilers

[CAESAR32]

Hey I have a job to do soon on a big house that has 2 boilers in at the moment one is a combination boiler which is unvented. The other is an vented boiler. Is it possible these 2 boilers work together or would you of thought the house has two seperate heating systems?

 

[Biggles..]

2 seperate heating circuits.

 

[CAESAR32]

ok any reason why it may be done like this?

 

[sambotc]

If you link the 2 together then either you will be filling the system with the filling loop until you realise water is ****ing out the overflow from the F&E tank, or the combi will be running at a low pressure determined by the static head supplied by the F&E tank. It could work but depends on what the min pressure required to run the combi is. (remove filling loop too )

HTH Sam

 

[CAESAR32]

ok thanks I need to have the system drained for a few days. Is it ok just to tiy the ball cock off the header tank up. Or would it be better to turn the mains off for 10mintues and cut a service valve in and turn this off?

 

[sambotc]

Depends what system your working on. I always cap cold main to F&E if it's an overnight thing, don't fancy the ballvalve letting go at silly O clock and me tucked up in bed