Help required on Essex Flange Vs Surrey Flange

Discussion in 'Plumbers' Talk' started by John 3G Engineer, Sep 4, 2005.

  1. John 3G Engineer

    John 3G Engineer New Member


    I moved into a new house and noticed that my power shower was very weak. Under advice i installed a Surrey flange but i have since read that a surrey flange should be used with a pump above the tank because it restricts the flow.

    I have read that an Essex flange would be far better and increase the pressure of my shower.

    Does anyone know the answer to my problem? would an essex flange be worth installing?

    Also, i have heard that my pump should be a maximum of 4 metres away from the hot water tank. Mine has about 9 metres of pipe between the pump and the tank. Should i move it to improve things ?

    Any help is much appreciated as no one has been able to answer this problem so far.

    Kind regards


    If you need any help on 3G telecommunications then i am your man. Its the only thing i am good at.
  2. britishblue

    britishblue New Member

    Hi John

    Most pump manufacturers recommend that the pump is as near to the hot water cylinder as possible and preferably level with the base of the cylinder. I think that above the cylinder is one of the least preferred positions because of the possibility of trapping air in the pump. Your Surrey flange should do the job, although the flow through an Essex flange is greater because it is not sharing its space with your normal hot water outlet.

    Is your pipework up to the punp 22mm or 15mm? The size after the pump is not so critical, but you will get better performance if the supply to the pump is 22mm. Also as few bends as possible in the pipework, and drawn bends rather than elbows will help the flow.

  3. John 3G Engineer

    John 3G Engineer New Member


    Thank you for your prompt reply.

    Out of interest i may plumb in an Essex flange and see if there is a difference. I also may try to reduce the distance between the pump and the tank to around 2 metres.

    I have 22mm as close to the pump as possible then 15mm for the last 10 inches. Is that good enough?


  4. mj

    mj Guest

    Booster pumps push water out, they rely on gravity to supply them. That's why they work much better when sited near to the supply tanks. Moving the pump close to the tanks will only increase the flow rate, not the pressure.
    It could be that the pump is faulty or just not powerful enough for your requirements
  5. John 3G Engineer

    John 3G Engineer New Member


    Thank you for that information.
    With this in mind i will now move my pump as close as i can get it to the tank which will be from 9m down to 2m. I will also change from a surrey flange to an essex flange.

    If that does not work then maybe i do need a new pump.


  6. chris clifton

    chris clifton New Member

    mj wrote

    Booster pumps push water out, they rely on gravity to
    supply them.

    Not true. The supply to the pump will be "sucked" into the pump, or rather pushed by atmospheric pressure acting on the water in the feed tank. Gravity will only apply in as far as the shower outlet is below water level in feed tank. Height of pump in relation to feed tank is immaterial. Best to keep all supply and delivery pumps as short as is practical, and of large bore, to minimise pressure losses due to resistance of pipework.
  7. rocketron

    rocketron New Member

    I took an essex flange off line, as being fitted on the side of the hot water cylinder you run out of hot water quicker than if you came out of the top.
  8. Scousemouse

    Scousemouse New Member

    ChrisClifton - yours are not the accepted views of those who make the pumps , or have tried it! Suggest you look at the ST installation bumph?

    You risk cavitation in the pump if you have insufficient head, and entrainment of air.

    It's usually expressed that pumps pump better than they suck, which will do.

    There's a trap to fall into if using a Surrey (or Warix) flange. If the hole in the top of the cylinder is small (eg 3/4"), perhaps because it has been bushed down (eg from 1 1/4"), then the waterways are quite restricted.

    Essex flanges are easy to fit if you have exactly the right size holesaw - 1 5/16" for 15mm or 1 1/2" for 22mm.

    Always get the "non stop-end" variety of Essex, so you can shove the pipe into the tank and avoid picking up bubbles which rise up just inside the sides. To get max volume out of your tank, you can simply bend the pipe upwards inside the cylinder! The amount of water you get with the different flanges depends on the height of the end of the intake pipe. Remember Surrey/Warix flanges have dip tubes.

    If you sucked really hard from any flange you increase the risk of bringing the level of water in the vent pipe down into the cylinder, and your pump. This is much more likely if you have a small (ie 22mm) or resistive feed pipe from the cistern above. Also, if you do bend the pipe on an Essex upwards, you have less margin of safety. One danger, which Mira make a fuss about, is that an electric immersion heater could become dry, so it would "blow".

    You CAN avoid using a flange at all. Stuart Turner and Mira recommend taking the HW out of the cylinder up at 45ยบ, and taking the shower feed off the bottom of the pipe. (Except for 4 bar pumps). I don't fancy the idea - too much plumbing to do and you would get convection currents up the pipe, cooling the cylinder.

    Oh, when putting in an Essex, do up the compression connection on the pipe before you fit it. Much easier to hold the flange, and once the flange is in there's nothing to hold, to do the comp nut up.
  9. Agile

    Agile Member

    If you can manage the 3G RF and particularly the software and the printed antennas then I would not have thought a simple bit of plumbing would present any difficulty.

    I found the TACs system hard enough so switched to boilers!

  10. John 3G Engineer

    John 3G Engineer New Member


    Sounds like you know a bit about 3G, are you in the game?

    RF, Optimisation, RNC's, WBTS and troubleshooting i find interesting and easy. Plumbing is ok but when you start messing around with pumps, flanges, 22mm, 15mm, distance from tank, gravity, air locks etc etc i find it can get confusing and need the advice from experts like yourself.

    I have re-plumped my power shower twice now under bad advice which is why i came here to ask your adivce. I am very happy with all the advice i have received and although my shower is fairly ok now i will re-plumb it the way it should be. It makes a nice change from messing around with RF frequencies.


  11. Jonny5stars

    Jonny5stars New Member

    The New Team shower pumps website has useful info about installation. Following their advice I didn't use a flange but put a Tee into the vertical vent pipe (22mm) to supply the pump and this works fine. My pump in sited underneath the hot water tank with about 3m 15mm pipe to the mixer valve.
    Another thing to consider is whether flow restrictors are fitted to your mixer valve. Some mixer valves recommend fitting flow restrictors (plastic washers with varying sized holes) to improve water conservation. I didn't fit them in mine as I suspected would probable impair pump function. Just a thought.
  12. Scousemouse

    Scousemouse New Member

    the pump

    I only ever did this twice - the second time it didn't work so haven't done it since! (sucked air)

    What flow rate do you have at the shower, Jonny?
  13. Jonny5stars

    Jonny5stars New Member

    Haven't measures flow as such but can only describe as powerful, certainly enough that you're always standing in water as the plug hole can't drain it away fast enough.
    Haven't had any problems with sucking in air either.
    Was put off doing an Essex flange - liable to knacker my water tank. Tank is not new and worried about taking seized on nut of top of tank to put on Surrey flange.
  14. rocketron

    rocketron New Member

    The new team shower pump co, refused to renew a shower pump of their make that leaked at the main joint that would open up to the impeller. The hot water to the pump was teed off from above the tee to the exspansion tank, this is bad practice. The cold water to the pump was taken from the cold feed to the bathroom, even though it was 28mm pipe. Cold feed must be fed direct from the cold storage tank.

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