In message , John
Rumm writes
On 27/08/2016 09:12, Tim Lamb wrote:
Now stripping out plumbing and electrics.
Is it a hanging offence to use a 15mm compression stop end on a gas pipe?
No. Compression and capillary solder fittings are acceptable on gas.
OK.
There is no provision for locking the supply shut off valve in the
outdoor meter cabinet. The 15mm is T'd off from the boiler feed and runs
across ceiling joists which are coming out.
Also Megaflow experience.. There is ample mains pressure here 4-6 bar so
the system can run at the designed pressure. I am considering pipe
routing (to minimise hot water arrival times) and wonder if 15mm gives
adequate bath fill flow rates.
At those pressures (although note that an unvented system will normally
have a PRV bringing the operational down to around 3 bar) you should
still get fast fill times. What you may find is you get a bit more
noise, and a more notable drop off in performance when other users in
the property are drawing water.
See http://wiki.diyfaq.org.uk/index.php/Unvented_DHW
Yes. There are a few potential *gotchas* in there.
Annual maintenance. Any legal implications or professionals involved?
Careful pipe routing should minimise drawoff pressure variations ie.
separate feeds to kitchen/bathrooms/basins.
The house is chalet /bungalow so header tanks not really practical.
20l/min could be tricky but I might be able to enlarge the main supply
pipe as part of another project.
Also any thoughts about plastic piping for plumbing other than
underfloor heating? Noise, reliability for hot supply etc.
If assembled with care, then performance and reliability seems ok. For
some applications its a massive time saver on installation. Main
downsides are it looks clunky and the fittings are pricey (but offset
by lower pipe prices). Also has the advantage of being easier to
dismantle if needs be.
I am planning boxed in ducting for the main runs. To facilitate first
floor underfloor heating I am going to cross batten the joists.
Cold/drinking water runs may need ca-)
--
Tim Lamb