Plumbing shower booster pump without connecting to electric supply mains

Page 2 of 2  

wrote:

Oh right, I see what you mean now... Hum, I'll take your word for it ! :~)

Not quite sure what you really mean here.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Have we been taken over by uk.legal? :-)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

No, just uk.politics...! [ see the thread 'IMM fodder' ]
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 03/02/2004 Ghazali opined:-

The pressure will obviously be more with the pump running, therefore more chance of leaks. I would be inclined to fit a 13amp plug on the pump system and plug it into an extension to try it. Be very careful of the earthing arrangements and do not be tempted to do any more than test it with this arrangement.
--

Regards,
Harry (M1BYT) (Lap)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Why?
I had mine plugged into a 13A socket. The socket was RCD protected to 30mA, although obviously not itself in the bathroom, as having a bathroom socket is not allowed.
Christian.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It depends on where the pump is.
Mine is in the airing cupboard in a bedroom. I changed the immersion heater FCU to a fused one, spurred off a 13amp outlet, and connected the shower pump using a 3amp plug top for ease of connection and maintenance.
If it's in the bathroom, I would connect to an unfused, unswitched flex outlet, running off a 3amp switched FCU somewhere accessible outside the door.
If the supplying circuit is not RCD protected use an RCD FCU. See http://www.screwfix.com/app/sfd/cat/pro.jsp?id 770&ts!503
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The advice looks unanimous. Thanks guys for your help. I'll ensure I have a plug fitted to it when he does the pluming.
Incidentally what will happen to the pump if i test it without any water flowing through it (i.e. just air). I've heard this can be terminal - but is the effect immediate - or does it need to happen for a few minutes before it dies out on you ?
BTW - I won't be trying this - I was just curious.
GAZ
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Most don't switch on when energised until they sense water coursing through their veins. Pressure switches I believe - that's how they know when to switch on and off.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
<snip>

AIUI it depends on the construction of the pump, some will self destruct promto, others will be OK, so unless you know what you're dealing with.....
BTW this is pumps in general and not specific to shower pumps.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ghazali wrote:

2.25bar? You like an invigorating shower then, or is the shower upstairs from the pump?
We have an S-T 1.4bar twin impeller with about 5m of 15mm pipe between it and the shower and that is more than powerful enough but the pump and the shower are on the same floor.
One thing to be aware of is that they are quite noisy so bear that in mind when siting it. Ours is in the airing cupboard, sat on the slatted shelf, which is just studded walls and it makes a lot of noise in the adjacent bedroom. If I'd have thought about it beforehand I would have put a piece of paving slab on the shelf under the pump. Unfortunately there isn't room to lower the shelf to retro-fit one.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The shower head I purchased from www.bathstore.com specifies a min of 2 bar to work adequately.
Cheers, Rob.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It's a 2.25 bar because I picked it up second hand off Ebay. However, I wish I'd read your post earlier regarding noise. I have put the pump under the bath and on the floorboards. You can imagine the noise - it's very loud. I snapped it up because I saw that it was a Stuart Turner Monsoon, which are very highly recommended and also quite quiet. What I had failed to research was that it is only the brass bodied ones that are known to be quiet. Mine is the 'engineered plastic type'. I had never had experience of a pump before - and did not realise they can be as loud as they are. Of course, if I want to put it on a concrete slab that would mean having to get the plumber round again!
Anyway, in retrospect, having the 2.25 bar (as oppose to being lower) was a blessing because for some reason the rerouting (due to different bath position) of the 22mm cold feed from the loft storage has resulted in very poor cold pressure. (The shower mixer doesn't even go on when you press the mixer/shower button due to such bad pressure). I suspect its an airlock, but it could also be the pump. My plumber tried to suck out the airlock with some but insufficient success. He also tried to blow it out from the top (near the tank itself). Subsequent to this I have tried to cover up the mixer with my hand whilst opening up the hot to try and let the hot run up the cold pipes - even this has failed. Still, my point is, at least the pump gives me a decent flow.
If I can't solve this problem of bad cold flow (and also the noise of the pump)I am thinking of doing the following......its controversial, so please give your expert comments.
I am thinking of running both the basin mixer and bath shower/mixer cold taps off of the mains, whilst still having the hot from the hot cylinder.
My thinking is that I will turn up the thermostat on the hot cylinder so that it gives much hotter temperature, and then I will only need to use a small amount of hot flow in the mixer shower, thus utilising mainly the increased pressure/flow of the cold mains, whilst still getting a decent temperature.
Now I know it is not the done thing to do this, but before giving your comments please consider the following:
1. A kithchen sink mixer also usually runs cold off the mains and hot from the storage cylinder, yet I never hear pple complaining about 'pressure imbalance' for washing up purposes. Why is it any different for a shower.
2. I usually have an early morning shower, at a time when no-one else is using any other water supply in the house, so there is no risk of any sudden temperature/flow change from, say, another tap being used elsewhere.
3. Because of the usual daily timing of the shower, surely the mains pressure will also be similar. (I have heard it can vary depending on how many other pple are using it on the street, or at different times of the day).
4. If the water is coming through a shower mixer (i.e. pre-mixed), why would a pressure imbalance between hot and cold have any noticeable effect?
BTW: I'm not a plumber remember - so please could any comments/suggestions be of a sort that I can understand and relay to my plumber in layman's terms. Cheers
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"Ghazali" wrote | I am thinking of running both the basin mixer and bath shower/mixer | cold taps off of the mains, whilst still having the hot from the hot | cylinder. | 1. A kithchen sink mixer also usually runs cold off the mains and hot | from the storage cylinder, yet I never hear pple complaining about | 'pressure imbalance' for washing up purposes. Why is it any different | for a shower.
A kitchen mixer does not mix the H&C waters inside the tap, if you look closely at the kitchen mixer tap outlet you should see two spouts (often concentric, with the cold on the outside so the tap remains cool to touch). The "mix" happens in the air outside the shower.
A shower mixes the H&C inside the unit, and with a pressure imbalance the high pressure cold can push the low pressure hot back, so you don't get a mix.
Also, from a safety point of view, you usually only have your hands under the kitchen tap and can pull them back quickly if it's too hot. With a shower, you're confined inside the shower cubicle and your whole body is vulnerable. Most people also expect a kitchen tap to be hot-hot.
| 2. I usually have an early morning shower, at a time when no-one else | is using any other water supply in the house, so there is no risk of | any sudden temperature/flow change from, say, another tap being used | elsewhere.
That may be your current lifestyle, but what happens if you have visitors or change your routine for any reason.
| 4. If the water is coming through a shower mixer (i.e. pre-mixed), why | would a pressure imbalance between hot and cold have any noticeable | effect?
See first point.
Bear in mind too that if you have your pump sucking from the mains (which may not be allowed under water regs) and you have low mains flow/pressure, and you are running the shower, the loft tank will be emptying and its ball valve will open to refill it. However, if the pump is sucking all the mains water for the shower, no mains water will go up to refill the tank and then the HW cylinder, air will get into the pipes (because the ball valve is open) and you'll have the possibility of another airlock.
If the pump suction and the layout of the pipes is such that the hot water cylinder is sucked dry, that may do it no good (those cylinders have almost no structural strength without the weight of water inside them) and as the heat from your boiler will have nowhere to go the boiler might overheat. All of this is somewhat hypothetical and worst-case, but it's not sounding like a good idea so far.
What you really want to do is have H & C waters at similar pressure going into a *thermostatic* mixing valve. The best thing really is (although I'm not an expert) to sort out that cold feed piping.
Owain
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
---8<---

You mean the _pump_ doesn't turn on when you press the button on the bath/shower mixer tap ? So how do you get the pump to turn on?
I assume you have separate cold feeds from the tank, one for the hot water (going into the bottom of the HW cylinder) and another for the cold taps in the bathroom. I also assume your plumber has taken the cold feed to the pump from the cold supply to the taps.

Which it would, if they are both fed from the same tank in the roof and are therefore at the same pressure. You can use that trick on a kitchen tap to clear an airlock in the HW side because the cold is at mains pressure.

---8<---
I'd get the cold water supply sorted out. If it's an airlock you can test for and fix it by connecting mains cold water via a hose into a cold tap whilst checking at the tank in the roof to see if air is blown out of the connector at the bottom of the tank. This'll show that there was an airlock and clear it. I'd want to examine the pipework run to try and eliminate airlocking in future.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I've just fitted a 2 bar pump (the 2.25 bar one from Screwfix was DOA) and it's just right through my bathstore.com shower head. I was tempted to fit a smaller one but glad I didn't in the end.
Rob.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Where is the pump located ?
Have you placed it on top of a concrete block or not.
Is it very loud?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Right under the bath at the front in the middle. It's a bath-shower design so there's a reasonable amount of space there. It's a bit tight with all the pipes running through to the basin and bath taps (directly above).

Nope - the instructions say don't fix it down so we haven't. Sits directly on top of waterproof plywood which is in turn screwed into the floorboards (ready for tiling rest of floor). Only thing holding it in place is the pipes coming out of the top.
On this model (and the screwfix 2.25 bar one), they supplied push-fit plastic pipes coming out of the top. They also suggest using as few 90 degree bends as possible. The fact that these push-fit pipes stick up about 8" meant that we would have to have used two very tight bends to get the pipes back down - they might also have fouled against the side of the bath which leans out towards the top. Therefore, we've replace the push-fit pipes with flexible metal braid connectors. Bit pricey but makes removing the pump far easier. Might put one little screw in there.

Well this is the biggest surprise of all - it's no where near as loud as I was expecting. I've fitted the Wickes pumps in the past and they sound like a jet engine. The B&Q 2.0 bar one is very quiet - recommended.
Cheers, Rob.
PS. Don't know how loud the 2.25 bar Screwfix was as it never worked :-(
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.