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  1. N

    Different flow rates on ground floor

    Hi, I've bought a four bed house, it's about 20 years old and has an adjacent garage. It has a downstairs toilet, utility room and kitchen and upstairs there's a main bathroom and an ensuite shower room. It has a vented system with boiler in garage heating cylinder on landing and a 40 gallon...
  2. A


    Hi all I have a 3 bed semi work in progress at the moment. It's fed off of a 15mm incoming copper water mains pipe which then branches off in 15mm pipe to feed the bathrooms, boiler, kitchen etc. It already has a Worcester Greenstar 28i Junior in good nick on the 1st floor landing cupboard, a...
  3. T

    flow and return for radiator

    Hello, I have a Worcester Greenslave 12/18, and I am about to change a radiator. At the moment the rad is fed by the same pipe, the feed I think, but as the return pipe runs right next to it, can I plumb the rad into the flow and return without causing problems for myself? Will this work, or...
  4. S

    Low profile shower trays and flow rates

    I’m considering the JT40 shower tray, along with the matching JT90 trap. Their blurb states it can shift 48 litres / min. Looking at the flow rate for a Grohe bar shower, for example, it’s quoted at 26 litres / min at 3-bar and this is approximate to what my pressure is and my flow rate is...
  5. O

    Loading unit flow rate Vs simultaneous use flow rate

    Do any one know why flow rate given by loading units calculation doesn't match for simultaneous use?
  6. P

    Leaking flow pipe on Baxi 105e

    Hi, I've got a leaking flow pipe coming from the main heat exchanger. There is slow drip where it connects onto the main heat exchanger. Before I take it all apart could someone tell me if it's better to replace the whole flow pipe or can I just change the seal on it?. Kind regards, Joshua...
  7. scott_d

    Isolation valve flow limits?

    I know it depends on pressure but is there a rule of thumb limit to the litres per minute that can pass through a cheap 15mm isolation valve?
  8. S

    Joining flow and return as temporary measure

    Forgive my ignorance, but i have (Speedfit) 22mm flow and return pipes that feed three rads (10mm) and the connectors are currently situated in just about the worst places imaginable! I am looking to move the pipework, as well as tidy it all up, but may not complete this PITA task before having...
  9. Milan5baros

    HELP - Back to back WC's issue with cross flow

    Morning all, Struggling to resolve a problem. Back to back WC's in a fourth floor flat and the waste from toilet A(main bathroom) transfers into toilet B (ensuite) we have installed the McAlpine ARB 1 anti-cross flow valve on each side but it has only stopped solids and there is still some...
  10. G

    Warm flow combi boiler /No hot water

    Need help please... My Warmflow oil fired combi boiler will not supply hot water to my domestic taps but the central heating works fine. This is a dual pump system. I have linked out the connections on the boiler stat which causes the hot water pump and system to work and able to get very hot...
  11. C

    Shower valve model identification

    We had this shower installed in 2001 and yesterday the flow valve started to go on the blink. The knob has become harder to turn both on and off and the water shuts off. I can access the unit and I know how to isolate it and I am a pretty dab hand at 'stuff' Can anyone identify the model . I...
  12. L

    Will lowering water tanks by 15cm have any noticeable effect on gravity flow system?

    Hello, I live in a building that is a conversion of two terrace houses into several flats. We have 7 levels (basement, ground, 1st, 2nd, 3rd, 4rth, and 5th), and each level has two flats, except for the 5th floor, which is the attic and on one side there is a small studio and on the other side...
  13. G

    Vaillant ecoTEC Plus 938 - Low Flow Rate

    Hi guys. Hope you are able to help me, and thank you in advance for anyone who can contribute. I've got a Vaillant 938 and notice that the hot water output isn't near the claimed flow. I've tested the pressure at the stop cock and it's around 3 bar. I've tested the cold flow rate from the...
  14. C

    Low water flow to whole house

    I have a pressure reading of 75 psi to my house but the flow is very poor. We do not have a water softener or pressure regulator. The flow is about even on hot and cold taps. We ran a 5gal bucket test and after over 1min we were not even at half. This started about 1 year ago and has gradually...
  15. J

    Dropping flow rates over time.

    Hi folks. I'm looking for advise for troubleshooting dropping flow rate that I could look into myself until we are up and running and I can get a professional in. Over the last 6-8 weeks I've noticed that our water supply is dropping in flow rate and today I measured a tap running at 3.5...
  16. 2

    Recessed Shower Valve No Flow

    I've just fitted the recessed dual shower valve photographed. Flow was fine until I went to calibrate the temperature this morning, so twisted the bottom cartridge and adjusted the flow on the isolator valves. now there is no flow out of the head at all (isolation valves fully open) having put...
  17. S

    Low pressure/low flow

    Hi All, I live in a 400 yr old house although the pipework is only 3yrs old from the internal stopcock. I have a low water pressure / low flow problem that I wish to sort out. It's a 25mm incoming pipe stepped down to 22mm internally which then reduces to 15mm into the various taps. I have a...
  18. R

    Does air lock affect flow rate in UFH

    Hi all, having issues with my underfloor heating . Flow doesn’t stay hot as return just stays cold even though boiler is operating as it should . My question is does an airlock reduce the flow rates ? I can get good flow 4+ ltr / min through the loops but still the return and hence flow stays...
  19. U

    underfloor heating. one section not heating.

    Problem with activator in just one area of the UFH system. I don't know how to take off the activator to check the pin. No problem with water flow. Not sure how to handle the flex coming out of the activator. I know the pins aren't working as the water gauges are not responding (that's what...
  20. R

    Underfloor heating flow won’t get up to temp

    Hi all. As above having issues with my UFH. Boiler fires up and works as normal . Issue is the return stays cold and as such when the boiler switches off when it reaches temp the flow stays about 35 degrees and the cycle continues . Have had it running with just one short loop open , pump on 3 ...
  21. Z

    Idea for those who have cash flow problem

    I had a terrible time finding a plumber and I am trying to think of a way to help him as I have one whom I trust implicitly thought that I could put a Medium sum of money in his account specifically to cover labour on future jobs As it’s only labour that is covered then there is no risk to...
  22. D

    Concern over flow of electric shower

    Hi, I have water immersion heater on a timer. Problem:I need more instant hot water - 5 people in house having daily showers. Currently we have 2 bathrooms which are fine for showers and pressure is decent enough (until hot water runs out!) There IS a pump to increase the pressure which works...
  23. Minidriver

    Boiler dhw flow adjustment

    Hi guys. New here. Basically I bought this house 2 yrs ago. Back when I bought it I took over an existing plan with British gas for my boiler servicing. Upon first service, I asked about hot water as if you turned the bath tap on more than 1/4 turn it ran like warm at best. He said he...
  24. W

    Why does oil not flow from elevated tank

    I have a Rayburn 308K oil burning stove (uses concentric wicks) It is fed from a tank which is around 3m (10ft) above the inlet of the stove. I have it around 20 years. Ever since I got it, if I run out of oil, the stove will not light after the tank is refilled. The only way I can get the oil...
  25. T

    List of DUAL FLOW taps

    Does anyone have a list of dual flow kitchen taps both mono and deck mixer types for mixed pressure supplies - Mains CW, Gravity hot. Trying to find one is a bloody nightmare. Thanks in advance.
  26. milleniumaire

    Does a waste flange affect flow rates?

    As part of a bathroom refurbishment I'm installing a new low profile shower tray and a 90mm waste. I'm looking to use a McAlpine 1.5" hi flow shower trap, which gives 42 l/m flow. There are various flanges available, but the one that would appear to give the best flow is the ST90CB10-HP2...
  27. M

    Thermal store combi boiler, hot water flow rate.

    Can anyone tell me the hot water flow rate on a thermal store combi boiler? As opposed. To a 40kw combi that will deliver nearly 16litres per minute. And any recommendations for a good thermal store boiler thanks.
  28. T

    HIU Flow Rate Dropping

    Hi All I live in a new build block of flats. We all have HIUs. This model. Type 2 HIU Connection for Primary & Secondary Heating Circuits - Switch2 - https://www.switch2.co.uk/product/type-2 The entity that owns the system didnt maintain it very well so they just had to flush the whole...
  29. Plumbase Spares

    Fluidmaster: Airgap Launch & the Issue of Blue Water Back Flow

    Fluidmaster recently released their new range of flush valves – the Airgap 6000 series. Designed and manufactured in the UK Fluidmaster’s new range is an essential for plumbers who install, repair, or conduct maintenance on toilets and is the only adjustable flush valve on the market today that...
  30. V

    New circulating pump. Low flow

    Hi guys. I live in a bungalow with 14 radiators. Closed loop heating system The heating is zoned so that individual areas or hot water can be independently heated. All radiators and heating cylinder are at ground level. My boiler is 7 meters away from the house in the garden. 11 meters...
  31. R

    Will low water flow affect the function of an electric tankless water heater?

    I have a cabin about 300' from my well and about 30' elevated from the well. The water heater doesn't work properly. The flow is low through the tankless electric water heater. Is it necessary to increase the flow? If so, how am I able to do that?
  32. siricosm

    Is a flow switch really necessary?

    I am contemplating installing a heat bank type thermal store, with an external plate exchanger for DHW. The pump on the primary (tank) side of the plate exchanger is usually controlled by a flow switch on the DHW side. I am thinking to use a modulating pump (Grunfos apha2) and a thermal...
  33. M

    Radiator water flow noise - Can anyone help, please?!

    Hi, Since having some house renovations 2 years ago, which included adding two extra rads, replacing others and re-plumbing the boiler , I have suffered from quite loud, (but variable) 'water flowing' hissing noise, which is especially noticable from the first two rads on the system (which...
  34. B

    Secondary Return Pump Noise / Air ?

    Hi, Recently I noticed that we were running out of HW more than expected, perhaps it’s people are taking more baths but I wanted to check out if the pair of Vaillant uniSTOR’s were both heating, thinking that maybe I had a problem with one of the Zone Valves were not heating one of the tanks...
  35. H

    Mixer tap weaker flow when tap turned to maximum

    I have a kitchen mixer tap with one simple lever controlling temperature and flow. The street water was cut off for a few hours. After that, the hot water flow worked as before, but the cold water flow was very weak. With the tap set to cold, if I open the tap about half way, the flow is the...
  36. A

    Any advice on Wickes shower flow diverters?

    We had our bathroom redesigned in 2015. The builder is no longer reachable and never supplied paperwork for the equipment installed. However a wee bit of homework and I have established that the shower (with overhead rainshower and handheld attachments) came from Wickes, their own brand in fact...
  37. M

    Water does not flow trough the pipes

    Hi , i have this situation that once every few months the water stops from flowing from the tank to the house. So i go and disconnect the pipe from the 2nd filter and wait for half minute and water start flowing again. I made a drawing here on the picture to show how is set up. I was wondering...
  38. P

    Best high flow water softener?

    Hi All, posting for the first time so hope this question is in the right place. Which water softener would you recommend for use with a megaflow system where you want to maintain high flow rates in all areas including the ensuite bathroom in the loft?
  39. B

    Mixer shower flow cartridge

    Evening all, hope this is in the right forum. I’ve got a triton bar mixer shower which is about 4 years old. Recently it has started to drip when turned off. I noticed yesterday if I push in on the end of the flow cartridge, the dripping stops completely. However it starts again once I let...
  40. L

    low flow rate, undecided on options.

    Hi I have an old property with a Low flow rate coming in from Mains. Old black imperial pipe from a long run. This is not a simple job to replace so looking for other options. It currently has 5 bar on standing but drops off as soon as one tap or shower is used. <1 bar. The property is being...
  41. K

    what shower head is fast flow

    so long story short... old shower going hot and cold new shower installed new shower going and cold heat exchanger plate replaced shower still hot and cold kitchen hot tap (not a mixer staying hot) just removed the shower head on the new shower to test the water coming directly through...
  42. R

    gravity flow

    Can gravity flow work in a circular motion ? e.g. 28mm flow rising from stove accross ceiling down through cyl coil and return to stove under floor I know that this system has to be vented properly. I could fully pump as an alternative as the cylinder is about 5 m from boiler. I have plumbed...
  43. J

    Higher Flow rate required

    Hi there, I'm away to first fix 3 x 1 bedroom flats. There is is One Cold supply in basement below flats, the pressure/flow rate isn't great. Without getting council to Install a bigger service is it possible to install a pump or Cold main booster to give adequate flow rate to these...
  44. K

    HELP - Identify Flow Cartridge ?

    Hi PF - Can anyone help identify Manufacturer of this Flow Cartridge - spindle is 71mm long, taken out using 23mm box spanner ... didn't get rest of the dims from my plumber before they put faulty part back into the wall ... have tried all usual suspects ... shower doctor, national shower spares...
  45. A

    Advice on flow to radiators after new boiler

    Hi All, I am looking for a bit of advice. I am not a plumber, just a DIYer who has been doing his own plumbing for more than 40 years. I understand how central heating works with flow and return but have a bit of a potential issue which I want to discuss. Bit of background first. I had a...
  46. J

    Flow gauges for central heating pipe work

    Whilst installing a new heat only boiler today I thought why don't we have flow gauges, in litres per min, on the flow immediately after the pump and then on the return near the boiler? This would allow us to see in real time the performance of the pump and the loss of flow around the system...
  47. R

    Trevi boost shower mixer, hot water flow only.

    Hi, Our shower only gives out hot water. The volume control works fine but the temp control turns fully both ways without any cooling effect. A plumber has tested and said that cold water is reaching the mixer ok,( the separate bath mixer tap below works fine with hot and cold ). The plumber...
  48. J

    Will a new Combi boiler improve shower flow??

    As the title says. I have been going round in circles deciding what to buy or get fitted (with a raft of various advice).....the short story (so far). I have an old Combi boiler needs replacing and, I am having a new bathroom installed in October but, I want to improve the all round shower...
  49. A

    Version boiler flow rate.

    I have decided to go for the Version boiler when I get my system upgraded but I currently have a Glow Worm 35 store which gives lashings off hot water which ilike, so I'm looking at the 111-w as its the same performance as the glow worm, I did initially go for the 100w button I was a bit...
  50. townfanjon

    Gas flow rate table. .

    Guys , do any of you fine chaps have the figures for 35 mm copper tube flow rates ( 3 , 6 , 9 meters etc etc ) only one I have goes up to 28 mm . Cheers in advance