New CWST/Pump//Mixer shower install advice

19 Jan 2005
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United Kingdom
Hi guys, I'm planning to install a new mixer shower at home sometime in the next couple of weeks. And would really appreciate a bit of advice.

I have a gravity fed vented cylinder with a 40 year old zinc galv CWST in the airing cupboard. Wanting to put in a good mixer shower, I find I dont have enough head. 20mm on existing electric shower output, you can imagine the dribble I get from that.

After considering a pumped setup I realise I still need 100mm head for the pump to activate, so I have decided to upgrade the old CWST tank to a larger one, which I will place in the attic above the existing tank. This will give me the required head and satisfy the total water demand for the pump, shower and HWC.
Always remember mother telling me not to drink cold water from the bathroom taps, I realise why now, after looking inside the old galv tank. The crap that's lining the tank walls after 40 years, well... you've likely seen it all before.

I'm confident about doing the installation, just have a few questions.

I will be fitting a york flange, as I have a male connection to top of HWC, am I write in thinking about twenty wraps with ptfe on the union?

I will also be fitting a new 22mm cold feed to HWC. Currently it has,from galv tank 28mm copper gate-valved then reduced to 22mm and union to bottom of tank. This 22mm tank union, will it be metric or imperial threading. The tank has been in a long time. Will it be fibre wrapped threads?

I'm figuring I will need to get all this in, in a day. To minimize inconvenience. Does that sound about right, or from your experience is that a lot of work for 1 day?

If you need any info or pictures I can post them, If I can find out how to upload them.

Many thanks for your help/advice


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This is the state of my existing CWST:

Dont like to think I'm getting showered out of this!: [/img]

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