Sealed or vented?
Sealed or Vented? We want to hire a plumber to install a new heating and plumbing in our home. It seems that before we can get proper quotes or make progress, we have to make a fundamental choice between using a sealed or a vented system. It’s a large house (six bedroom), and we’re a large family of two adults and four teenage children, and our highest priority of all relates to water pressure. It’s vital that we can at least have a system which allows us to be running three or four power showers, at the same time, and not have the water temperature or pressure affected if someone then turns on a tap or the dishwasher starts up etc. Right now, this doesn’t work at all with our current system, even with one shower on, if a tap goes on too then we’re either scalded or frozen, or both alternatively.
I know little of the two system choices, other than the snippets I’ve picked up from plumbers so far. I’m told the advantage of a sealed system is no water tanks or pipework in the attic (so nothing to freeze), less risks of leaks going un-noticed and less risk of air locks (especially in an old house like hours where pipes do tend to go up and down a lot to get around the layout of the house), but with the disadvantage that cold water is based on mains pressure and the hot water only works on pressure, no pump like a vented system would have, so the more taps/showers that are on, the lower the pressure and the more likelihood of temperature changes when taps are turned etc. I’m told the advantage of a vented system is that the water supply to the showers will be from stored water (hot and cold) in the tanks, so constant pressure to all showers until the tanks run dry and much less impact of taps being turned on etc, but the disadvantages are tanks and pipes in the attic that can freeze, leaks can go un-noticed as no drop in pressure and higher risk of air locks…
How on earth am I supposed to make this decision which way to go? I only know I want us all to be able to have a shower without being scaled or froze when the dishwasher starts or one of us stops our shower (and of course I’d prefer not to have frozen pipes, leaks and airlocks). Can anybody help me shine some light on this, how to make the decision, are there other things to be considered, are there ways around the disadvantages of either solution? We really need help here…
Addition: Some replies I got asked about our current cold water pressure. I did a test, using the kitchen tap which is about as close to the mains as possible, I'm getting 10 litres per minute, though it's much slower if I go to the upstairs bathroom taps, less than half that.
Last edited by stevenmarston; 11-17-2010 at 07:22 AM.