Advise need on unvented cylinder

[SL]

I'm thinking of getting a direct unvented cylinder, are there any makes to avoid / recommend.

There are 4 of us in the household, so I will be getting two showers fitted and a bath . What size would you suggest ? I was thinking 210 liter.

Thanks

 

[gas4you]

That size should suffice. Make sure whoever supplies and fits it is G3 certified and obviously with a direct cylinder you will need a competent and qualified sparks to connect up the two immersion heaters.

 

[Onetap]

I'm thinking of getting a direct unvented cylinder, are there any makes to avoid / recommend.

There are 4 of us in the household, so I will be getting two showers fitted and a bath . What size would you suggest ? I was thinking 210 liter.

Thanks

Look at the manufacturers' websites for Installation Manuals. Heatrae Sadia ones are good. Check the water flow rate (bucket, watch) and pressure (pressure gauge) and compare with their minimum recommended values before committing yourself. You may need a new service pipe from the mains to get adequate flow rate; you may find the pressure &/or flow rate is inadequate.

You would dispense with the cold water storage tank. This will be a disadvantage if the mains supply fails.

You need to be qualified to install them. Make sure the fitter is, check his card details with the Issuer (CITB, IoPHE, etc)

Ignore Water Systems (aka Doctor Drivel) when he posts the waterheaterblast video, he is the resident moron on this forum (and many others). I was installing unvented systems and doing research on the domestic models before they became legal in the UK in 1987. There has never been a burst of an unvented system like that in the video in the UK. Although the video is quite entertaining, it was intentionally rigged to burst.

 

[SL]

Thanks for the advise.

Pressure should be ok, as the first time someone uses the tap in the kitchen, they and the floor ends up getting wet.

The mains pipe comes up in the middle of the house, so could not be upgraded. I take it that qualified plumber (CITB, IoPHE, etc) would check the pressure and flow.

Steve

 

[Agile]

If they dont measure the flow rate dont use them!

Really the dynamic flow rate should be measured. Ideally 20 litres per minute @ 1 bar.

If there will never be more than 4 people then 210 li would be just adequate but I would suggest 310 li is better as the marginal cost is small.

Tony