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No. You can either pressurise the hot coil or you can use a power shower, either way tank not pressured, look at the diagram I put up.
Cabling for motorised valves
- Thread starter SJRSJR
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It’s too late to get power showers but please could you point me in the direction of pressurising the hot coil please? Everything I’ve read about vented cylinders says the tank has to be above all hot water outlets.Thanks
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Neither of those things happen.
If you really want it to be inspected annually, then it's done when the boiler is serviced for no or a tiny extra cost. Most people don't bother.
There is no boiling water, and it certainly doesn't 'fly about'. Stories you may have read about unvented cylinders exploding and so on are just that - stories made up by people with agendas, mainly those that want to sell you some pointless, expensive and complex alternative. Probably by the name of Gledhill or something similar.
The only example of an unvented cylinder exploding is a Mythbusters episode where they obtained one, deliberately removed all of the safety devices, welded all of the pipes and other outlets permanently closed and left it heating continuously via an electric element with no thermostat for hours. There are no circumstances where that could happen in any real installation.
Don't go there.
The viable options are
unvented cylinder if the mains water supply is suitable or can be upgraded so that it is
or a vented cylinder and a pump if it isn't and can't be.
Unvented cylinders are not new or fangled, they have been used all over the world for decades. Standard equipment in most countries.
Unfortunately in Britain, ye old vented piece with a disgusting open cistern in the loft still persists, and plenty of people are convinced that some instant water heater combination boiler effort is the only alternative. It isn't.
I don't know who mentioned explosions. But you can't just leave unvented cylinders unmaintained for years, else they will fail early and have to be replaced at cost ££££
Good news is that is easy to do yourself. Once a year you just move 3 valves/taps for ~10 mins, draining off the expansion, and job done for another year. I just put a reminder in my phone in June. (before peak summer heat) or 1 year after installation.
Instructions are on the side of the tank.
Good news is that is easy to do yourself. Once a year you just move 3 valves/taps for ~10 mins, draining off the expansion, and job done for another year. I just put a reminder in my phone in June. (before peak summer heat) or 1 year after installation.
Instructions are on the side of the tank.
Unvented cylinders do not need to be at the top of a house, as they run off mains pressure, with a small reduction.
Basically you have the mains water come into the "airing cupboard". Then you have a pressure reducing value with 3 outputs.
1. Water out supply to water cylinder
2. Water out to most of your cold taps in house (in reality this only needs to be showers with mixing values and mixer taps). This is nice to have as it ensures the cold and hot are at the same pressure for mixer taps.
My outside tap, cloakroom and kitchen mixer are direct off the mains, and I can't really tell the difference. But if you are in a high mains pressure area you might.
3. Pressure relief out "overflow"
To heat the coil in the cylinder, you need a supply and return from the boiler in 22mm.
3 way valves aren't really fitted these days with unvented.
Just have S plan. One 2 port valve for HW coil.
Although I was told my boiler had a bypass built in (on here), I seamed to need a bypass to return the water to the boiler when motor valves are all closed. Plumber will fit one. Not a big deal.
Basically you want your CH motorised cables to emerge at the same point as your CH stat wireless receivers
Basically you have the mains water come into the "airing cupboard". Then you have a pressure reducing value with 3 outputs.
1. Water out supply to water cylinder
2. Water out to most of your cold taps in house (in reality this only needs to be showers with mixing values and mixer taps). This is nice to have as it ensures the cold and hot are at the same pressure for mixer taps.
My outside tap, cloakroom and kitchen mixer are direct off the mains, and I can't really tell the difference. But if you are in a high mains pressure area you might.
3. Pressure relief out "overflow"
To heat the coil in the cylinder, you need a supply and return from the boiler in 22mm.
3 way valves aren't really fitted these days with unvented.
Just have S plan. One 2 port valve for HW coil.
Although I was told my boiler had a bypass built in (on here), I seamed to need a bypass to return the water to the boiler when motor valves are all closed. Plumber will fit one. Not a big deal.
Basically you want your CH motorised cables to emerge at the same point as your CH stat wireless receivers
Damm. This one runs of immersions. So Doesn't show boiler pipes.
But you get some idea
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Might prove unnecessary, but large metal object, can screen the signal from getting through.
As long as the metal isn’t in a line of sight between stat and receiver.
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