Best way to heat house and supply showers

[bluebaron]

I currently have an older house with a large new extension. In the old part I have two power showers, 15 rads (with Honeywell evohome valves) these are fed from two large cold water tanks and a hot water tank. In the new part I have a separate hot water tank supplying a power shower, and kitchen and Rads supplied from the existing C/H.

It all works fine but I want to try and simplify the system by doing away with the tanks (hot and cold) and I also need to Plumb a new en-suite with an extra power shower.

The last time a heating engineer was over he said I should rip it all out and fit a pressurised hot water system and do away with the power shower pumps.

does this sound like a sensible idea?

 

[Mottie]

Before you do that, you need to be sure you have the flow and pressure to run it.

 

[bluebaron]

I upgraded the main last year with a new 32mm Mdpe so all good there.

 

[oldbutnotdead]

It's not the best plan in the world. At the moment (if system has been plumbed correctly) your 2 power showers will be able to run at the same time with no noticeable pressure/flow variations. If you plumb your 3rd power shower to the tank that only has 1 shower on at the mo you'll maintain that level of performance and independence- the only real limit is how big the cylinders are (so how long til the showers exhaust the hot water).
You could go pressurised dhw either one monster cylinder (500l or so) or (probably better for your larger house) 2 x 250 or 300litre (reduce wasted water on running hot). If you still want to be able to run 4 showers at the same time without noticeable pressure/flow drops you'll end up limiting each shower.
You're also at the mercy of your local water transporter. They only have to supply 12l/min at 1 bar or so, your supply may be excellent now but if it did drop to statutory minimum there'd be little you could do.
If your current setup works and runs quietly and economically (all the lagging in the world on the cylinders and primary and dhw pipes) I'd leave it be.

 

[oldbuffer]

Upgrading the main won't do anything for the pressure, although it will improve the flow rate.