Shower running out of hot water quicker than normal

jon1981

Hi,

We have a mixer shower fed from a pump which pulls hot water from the hot water tank (essex flange) and cold water from the cold water tank.

We use to get easily 20 mins of hot water and now we are getting 5 mins max. The rest of the hot water taps in the house are still piping hot but the shower is running cold. We have not changed our heating schedule either.

Ive checked the hot water pipe feeding into the pump and it seems to go cool after about 5 mins so I'm ruling out the mixer taps and pump as the source and leaning towards some problem with how the water is being heated in that tank.

Any ideas of what i could check next?

Other possible causes, heated water from boiler not hot enough? Cold water filling the tank up too quickly? Hot water coil inside tank?

Thanks
J

Sleeper12

It could be the cartridge in the shower itself but more likely the pump needs repairing /replacing.

What's the make of the pump?

How old is the pump?

listermint

Is there still hot water in the tank ?

Common cause of this could be the element has scale build up and is actually not heating enough water anymore. It usually the simplest explanations that are the fault.

jon1981

Sleeper12 wrote: »

It could be the cartridge in the shower itself but more likely the pump needs repairing /replacing.

What's the make of the pump?

How old is the pump?

I don't think its the shower cartridge or pump as the hot water feed into the pump is running cold after 5 mins so not making it that far.

Pump is stuart turner eco, 1.5bar

jon1981

listermint wrote: »

Is there still hot water in the tank ?

Common cause of this could be the element has scale build up and is actually not heating enough water anymore. It usually the simplest explanations that are the fault.

Yeah there is as the sink and bath taps still get really hot water when the shower is running cold.

Wearb

With an essex flange its possible to have cold water at that level in the cylinder and still some hot left further up. But I suppose you understand that.

I assume your hot taps is supplied from the same cylinder and not a combi boiler.

jon1981

Wearb wrote: »

With an essex flange its possible to have cold water at that level in the cylinder and still some hot left further up. But I suppose you understand that.

I assume your hot taps is supplied from the same cylinder and not a combi boiler.

Thanks, yeah I know enough to be dangerous The taps are supplied from the same cylinder alright. The puzzling piece is that the water from shower worked fine up until this week.

Actually I told a porky, I had the system heating only water up until now, this week I switched over to heating both water and central heating. Could there be something in this?

Wearb

Do you have a pump overrun that might be cooling the cylinder? Do you have a boiler stove?

Puzzling thing is that the taps are hot (therefore top of cylinder) and water from Essex is cold. I can’t get my head around that, unless as I suggested in my first post.

jon1981

Wearb wrote: »

Do you have a pump overrun that might be cooling the cylinder? Do you have a boiler stove?

Puzzling thing is that the taps are hot (therefore top of cylinder) and water from Essex is cold. I can’t get my head around that, unless as I suggested in my first post.

Pump overrun doesnt ring any bells. Don't think so. We don't have a boiler stove. Yeah, a fecking mystery!

jon1981

Actually, I did remove the pump and mixer tap as the problem. But is it possible that a faulty tap mixer or pump could use up the hot water faster than normal?

benjovenjo

Did you ever get this sorted? Just wondering as have similar issue and can't make head nor tail of it. The shower runs out of hot water after about a minute but there is still plenty of hot water in the tank as evidenced by the hot water coming out of the taps.

K.Flyer

benjovenjo wrote: »

Did you ever get this sorted? Just wondering as have similar issue and can't make head nor tail of it. The shower runs out of hot water after about a minute but there is still plenty of hot water in the tank as evidenced by the hot water coming out of the taps.

If it something that has just recently started to happen then it is one of two problems.
Either the thermostatic cartridge on the shower valve needs replacing.
Or, the hot water is excessively hot and the thermostatic cartridge is functioning correctly to prevent scalding.