I am planning to re-plumb my house going back to the traditional tank in the loft system. The bathroom pipe work will be mostly 22mm Polybutylene. I am considering whether I should use a larger diameter pipe from the cold tank in the loft as far as the upstairs bathroom. The hot tank will be directly below the bathroom so this pipe will be refilling the hot tank as well as supplying the cold water to the shower. What do you think; should I go up a size?
Pipe size from a cold tank
- Thread starter CliffordBrown
- Start date
personally I'd use 1 pipe solely for the H.W Tank depending on the useage (if a large house then 28mm) if a normal 3 - 4 bedroom hose then 22mm should be fine, & a seperate feed to the shower, make sure that bot are fitted with "full Bore" isolators as if you fit normal valves you'll restrict the flow..hope this helps? & why go BACK????, fit an unvented cylinder...a lot less aggro
It is usual to run a seperate cold feed to the hot cylinder, fitted slightly higher in the cold storage tank than the outlet supplying the cold taps. This means that if the cold mains feed should fail for any reason, the hot supply should fail first, reducing the risk of scalding.
Having as few restrictions as possible in the cold feed to the cylinder will help minimise any pressure or flow changes at a shower if another tap is used whilst the shower is running. I would consider increasing the cylinder cold feed size if practicable, particularly if you are going to pump any of the hot outlets.
djsarge1973 - There's little point in proposing an unvented cylinder until you know the mains pressure and flow rate are suitable. Okay, you could fit a break tank and pump the cold feed, but you can do that, more or less, with a gravity system without the additional maintenance requirements of an unvented cylinder anyway.
Having as few restrictions as possible in the cold feed to the cylinder will help minimise any pressure or flow changes at a shower if another tap is used whilst the shower is running. I would consider increasing the cylinder cold feed size if practicable, particularly if you are going to pump any of the hot outlets.
djsarge1973 - There's little point in proposing an unvented cylinder until you know the mains pressure and flow rate are suitable. Okay, you could fit a break tank and pump the cold feed, but you can do that, more or less, with a gravity system without the additional maintenance requirements of an unvented cylinder anyway.
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