Not happy with with new unvented system, although it works fine. Shower pressure issue

[EvilDrPorkChop]

Just for your info an unvented needs a min of 3.5 bar and 20 lpm

Whilst yes that's true for it's optimum operating performance an Unvented cylinder at lower pressures and lower flow rates than this will still deliver decent performance, much better than a combi boiler.

For instance our Static Pressure is 2.5bar, i've never actually got round to measure the dynamic. But at this we get 18lpm at the large showerheads, and can run two rain head showers at once without much decrease in performance - more than what we would out of a combi.

So yeah it'd be ideal to have 3.5bar and 20lpm, however I don't think it's always essential. Many places round us can't even top their boilers up to 1.5bar the pressure is that poor! - and yes I agree in that situation a Unvented is pointless.

 

[Scott_D]

Is the shower new or the same as before the work?

 

[Gasmk1]

Is the shower new or the same as before the work?

judging by write up same as before a rain shower head which to me as the name suggest should not be thundering out but like being under a rain shower i suspect with the pump it made it too powerful now
it probably showers as it was designed to

 

[Scott_D]

Could have filters that need cleaning

 

[kash]

Yes you are right. An accumulator does not increase dynamic pressure, it just maximizes it, sorry I should have worded it better. Yes they are installed on the cold mains, hot water will be drawn from the cylinder, which in turn fills and supplies from the cold main accumulator. They can be installed virtually anywhere within the property but must be sized correctly as I said. If its boosting all outlets, hot and cold then this will be a large accumulator. What did you say your incoming pressure and flow rates is to the property? As mentioned above size of pipework, both into and around the property has a big part in what you'll achieve at outlets.

I'd only use it on the shower outets, the others are fine. If I used an accumulator, would I still use my shower pump too?

judging by write up same as before a rain shower head which to me as the name suggest should not be thundering out but like being under a rain shower i suspect with the pump it made it too powerful now
it probably showers as it was designed to

It never thundered out as such, but it was good hard pressure. Now its just like a nomal tap and mediocure flow.

 

[SJB060685]

Now that you're on mains pressure hot water I thought you wouldn't use a shower pump?

 

[kash]

Now that you're on mains pressure hot water I thought you wouldn't use a shower pump?

as I mentioned at , pressure is fine on all taps and outlets, it's just slightly dissapointing on the shower. I meant its still decent but its not as forceful as it used to be with the previous pump, which is why i'm trying to find out how I can restore this level of pressure from the shower, as a pump cant be installed onto the incoming mains.

Ideally, all i want is my hot and cold on the shower only pumped/high pressure - everything else is perfect. looking for the most cost effective solution as I dont want to spend an arm and leg as the new setup has already cost a fair bit.

 

[SJB060685]

Yes sorry I misread your comment, I read it as you wanted to use a shower pump again. As you said above this is a no. Pumps can be put on incoming mains but must be done properly with a breaker tank. This is used when your incoming mains is below 1.5 bar or so. You need to remember your old shower pump probably generated more pressure than what your incoming mains is, which will obviously reduce the performance of the shower.

 

[kash]

Yes sorry I misread your comment, I read it as you wanted to use a shower pump again. As you said above this is a no. Pumps can be put on incoming mains but must be done properly with a breaker tank. This is used when your incoming mains is below 1.5 bar or so. You need to remember your old shower pump probably generated more pressure than what your incoming mains is, which will obviously reduce the performance of the shower.

Well I do want to use my pump again, if it can be permitted to do so, but I understands it will need its own tank to do so. watch this space.

 

[EvilDrPorkChop]

Well I do want to use my pump again, if it can be permitted to do so, but I understands it will need its own tank to do so. watch this space.

To do that you'll need basically your old set up refitting just for that shower, then a way of heating a cylinder. If you're using a 4 bar pump, you'll be needing a decent size cylinder to supply this also....you're already in to a decent amount of cost to do that.

Seems madness to me. Are you not just being unrealistic about the performance of the shower? Surely if the cylinder has been fitted correctly and everything else is correct - Pipe sizing, filters clean, pressure, then you'll be getting more than a decent shower out of an Unvented HW system.