Bath mixer tap with shower attachment

[york310]

I have replaced my old bath taps for one with a mixer with a shower attachment. I know the temperature won't mix great due to low pressure hot water from the tank and the cold water from the mains. However, the water comes through the tap with good pressure but when I switch it to the shower head the hot water doesn't come through well at all even with the cold tap off. It just dribbles. The cold water comes through reasonably well as expected.

Any ideas?

[regulo]

The hot water pressure relies on the water pressure from the cold water tank in your loft, whereas the cold water is (usually) from the mains. To see if this is your problem, set your mixer to full hot, then raise and lower your shower head. If the flow reduces as you raise the head, then you have an insufficient head of water above your shower head. If that's the case, your only answer is to raise your loft tank. Or spend loads of dosh on a power shower pump.

[york310]

Thanks for the reply.

Would this pressure problem mean that it is ok and quite fast when running through the tap but just drips out of shower. This is just with the got water on full by itself.
You can feel and hear the flow at the tap but nothing at the shower head.

[regulo]

Almost certainly. Only other explanation is if you have a dodgy mixer tap (if the flow is fine with the shower head held at the same level as the tap itself, it is sure to be lack of "head" from your cold water tank). Sorry to be the bearer of bad news.

[johnk]

Is your cold water tank in the loft? Sometimes they are just a small tank on top of the hot water cylinder on the 1st floor so there would be hardly any head of water above the shower head.

[york310]

Flow is almost nothing but dripping even at bath height. It's not fitted to use as a shower really just sitting round the taps at the moment. The cold water tank is in the loft of a 3 storey house. The bathroom is on the 3rd floor as is the got water cylinder.

Thanks again for your help.

[regulo]

If that's the case, and flow is ok from the tap outlet, I would suggest there's a problem in the mixer tap diverter valve. Sounds like a return to the retailer jobbie.

[AlBags]

It's not correct practice nowadays to plumb up cold bath taps to rising mains. This does not help with bath mixers.

You should also check the shower hose for a collapsed/kinked lining. Better ones are bigger bore (like a Mira one) Cheap ones are half the size and restict flow considerably.

[alavahalf]

Dont forget that the Mira shower attachment has a different size collar, and is'nt compatible with the universal fittings found on most shower clamps/riser rails.

[AlBags]

Yep .. you could be correct, although Mira hoses fit quite a few others like Triton.
Check the thread then, if you want to change the hose.

[alavahalf]

No.. the thread is the same size ... its just the tapered collar at the end of the Mira hose that does'nt fit the universal fittings.

I know because I've been caught out once before (only once)...giving me a 20 mile drive back to the store :)

[mjwman]

Modern taps use a small bore flexihose to connect to the pipes. Your old taps were probably 22mm- these gave plenty of flow with tank pressure.
You will need to fit a power pump.
It is very easy to do and should cost about £100 from Screwfix or similar.

[AlBags]

Oh yes .. so where exactly in the shower fitting and hose does this power pump fit, then?

[KARL]

From your description I would say there is something odd about this - the hot water on its own runs fine into the bath but on its own through the shower hose held at tap level it merely drips. My immediate reaction is to thing there is something obstructing the water from getting from the tap to the shower rose. I suggest you remove the hose from the tap (assuming this can be done) and see if you get hot flow on its own. If not, knowing the bath-filler spout is at more or less the same level as the fitting (on top ?) for the hose, then the switch from bath-fill to shower is not working correctly. If you get similar flow (hot only) through bath-fill and hose fitting, then your problem is either in the hose and rose part, or else at the joining onto the fitting (washer scrunched up ?). The way to test the hose and rose is to run water through it by offering it to the bath fill (letting it lie on the bath bottom) and simply filling it and watching what comes out at the other end.

[KARL]

...ooops, think, not thing. Sorry

[york310]

I've been unwell so unable to return anything to the retailer yet.

I disconnected the hose from the tap to see if there was good pressure with the valve open and with the got water turned on by itself. It soaked my ceiling. It was quite powerful.

It must be the hose or shower head?

[regulo]

I would think so, if there's that much pressure available!!

[Justsurfing]

Take the flow restrictors out of the shower hose, most quality shower taps come with built in flow restrictors in the shower hose, take them out then all will be fine. sounds like an 6 to 8 litre per min flow restrictor.

http://www.youtube.com/watch?v=dKz2ZLhynm0

[Justsurfing]

Your problem is a simple fix:
Remove the flow restrictors from the shower hose.

http://www.youtube.com/watch?v=dKz2ZLhynm0