Andy Kaye wrote:

I read that it is not a good idea to have too many thermostatically
controlled radiator valve as it cuts down the efficiency but we only
have them in bedrooms.

Not really a problem with a modulating boiler since it simply reduces
its power output to mathc the reducing load, hence it maintains
operation in an efficent temperature range.

As for the original balanced flue it exits the house at chest level.
With a wall hung condensing boiler the exit for the flue will be at
about 7 ft. I didn't know if there were any building regs for the
condensing boiler flue like with conventional flues. I seem to
remember my father having to build an insulated stack up to the roof
in the past.

Therea are rules for how close the flue can be to windows etc, but these
are not that onerrous in most cases. 7" is good since it will be over
(most) peoples heads. It also does not want to be directed at a
neighbouring property if it is too close.

Culled from an Ideal install guide:

Terminal Position Minimum Spacing
1. Directly below or alongside an
opening window, air brick or other
ventilation opening 300 mm (12")
2. Below guttering, drain pipes or soil
pipes 25 mm ( 1")
3. Below eaves 25 mm ( 1")
4. Below balconies or a car port roof 25 mm ( 1")
5. From vertical drain pipes or soil pipes 25 mm ( 1")
6. From an internal or external corner or
to a boundary along side the terminal. 25 mm ( 1")
7. Above adjacent ground, roof or
balcony level 300 mm (12")
8. From a surface or a boundary
facing the terminal 600 mm (24")
9. From a terminal facing a terminal 1200 mm (48")
10. From an opening in a car port
(e.g. door or window) into dwelling 1200 mm (48")
11. Vertically from a terminal on the
same wall 1500 mm (60")
12. Horizontally from a terminal on the wall 300 mm (12")



--
Cheers,

John.

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