Any Plumbers on the Forum?

[JtB]

We've recently had a new thermostatic shower fitted and flow of the new shower is poor compared to the old shower. I don't know if its related in any way, but the flow through all our upstairs hot taps is quite poor now. When you turn on the hot bath tap (for example), the flow is ok for about 30 seconds then it starts to falter, in fact tonight it stopped all together. Our house is about 13 years old and for the last 6 years we had a water softener on the main water supply into the house. Until recently we have always had a very strong flow through our taps and showers. We have a gravity fed system and I was wondering if air might have got into the system when the new shower was fitted. I was also wondering if one of the valves that was closed when the new shower was fitted might not have opened properly again (for whatever reason) or if there might be a blockage somewhere. I have checked the header tank in the loft to make sure the ballcock is working and that's fine.

Any suggestions or recommendations would be much appreciated.

 

[Over The Hill]

Possibly air in the system. I have this whenever the system is drained down.

How I clear it is this-

1. get your garden hose pipe from a cold tap (on mains pressure) and go into the loft with the end wear a t shirt only as you get wet arms.
2. With the bath hot tap on you can stick your hand into the header tank and feel which of the outlets (if there is more than one) is running - it will have a suck to it like a bath plug but mind as it can be strong.
3. Shove the hose pipe in the header tank and into the end of the outlet pipe. (down in the water and in where the water is running out from) It should be a 22mm pipe so will go right in. You may also need to block around the hose to stop it running back so much with a ring of blu tack.
4. Able assistant turns on the hose and bath and the additional pressure should blow through any air.
5. Leave it running for a couple of minutes and if it works the flow is restored.
6. Brownie points earned are then lost if you let the hose leak all over the carpet when you come down.

Well it works for me!

You are in a prime hard water area and my hot tank only lasted 15 years before it had about six inches of deposit in the bottom clogging it up. Does the water softener soften all the water? If so then it should not keep building up and being a problem.

 

[Kirstie]

I don't know what kind of water system you have but we have just spent six months working this out. Like you, we experienced a gradual drop in hot water pressure and eventually the shower stopped working. We have a gravity fed hot water system and a condensing boiler, and a pump-driven shower (ie not an electric one). The pump started to make alarming grinding noises which was accompanied by a drop in shower pressure and temperature.

Our plumber originally thought that the header tank was too small and the shower had been piped in the wrong diameter pipe. So he doubled the size of the header tank, raised it onto a platform to increased the drop and repiped the shower in 22mm pipe. this made some difference to the hot water pressure but none to the shower.

We then changed the pump, the mixer tap, and backflushed the entire system to get any cr*p out that may have been causing a blockage. Again, this made a difference to the hot water pressure but not to the shower.

Eventually, after changing every element of the system, short of the water tank, we decided that the only thing it could be was the flange in the top of the water tank. This device (known as an S flange or Warwick flange) is effectively a spike which goes into the hot water tank from the top and its job is to separate the hot water from the air, and feed the hot water into the shower pipe. We discovered that this is a poorly designed piece of cr*p which wasn't supplying enough hot water to the shower, as the hole in it was too small. So, we had the plumber directly pipe the shower's hot water supply into the tank, thus negating the need for a flange. This has completely solved the problem and now we have a frighteningly powerful shower and good hot water pressure. typically, the flange was the cheapest part to replace, unlike the rest of it!

Soooo, check:

1. Whether the size of your header tank is correct for your system
2. Whether the pipes are the correct diameter for your shower
3. Whether you have a flange assembly in your water tank, if so, get rid of it!
4. Whether you need to back flush the system to clear it out (that's what overthehill has just described).

That's what worked for us, but it has cost us a fortune and has been a royal pain in the ass. I hope that our experience has saved you some money.

 

[JtB]

Thanks both. I will try out the back flush and if that doesn't work then I'll ask a local plumber to look at the flange.

 

[Kirstie]

Thanks both. I will try out the back flush and if that doesn't work then I'll ask a local plumber to look at the flange.

Now that's not a sentence you hear everyday

 

[ELL]

I know this sounds silly but my Mum had the same problem at hers when she had all her heating done. turned out the plumber just hadn't turned one of the stop cocks on