Electric Shower Cold in Morning

[Lokolo]

Hi All,

Before I get someone out I just want to ask here.

I have an electric shower which was working fine until a couple of days ago and now won't heat up in the mornings, we are talking 7am. It's a flat and water pressure around the flat is fine at that time (I can run taps and a bath easily, the combi boiler is still running).

Now I don't have a "Low Pressure" indicator on the shower.

This is the only reason I can think that would cause it not to heat (it's permeantly on "Reuce Temp" indicator) is the pressure.

Is there anything else that could cause this? It's been fine in the evenings.

 

[stem]

You don't say how severe the problem is, but it is completely normal for the performance of an instantaneous electric shower to fall as the weather gets colder, because the incoming water supply is also colder. 5 degrees makes a huge difference. Quite simply electric showers provide a fixed amount of heat via electric heating elements and when the incoming water temperature is lower, it requires more heating to get it to a comfortable temperature. The only way to do this is to reduce the flow so that the same amount of heat is applied to less water.

Having said that, some showers have two elements the smaller one is used for the 'low' setting, the larger one for 'medium' setting and both are on for the 'high' setting. If yours is like this, then it's possible that one of the elements has failed and you are only running with one. Although this doesn't sound likely if it's OK at night.

Was it OK last year when we were getting sub zero weather?

 

[Lokolo]

Hi,

Thanks for this. That does make more sense!

Unfortunately I bought it 3 months ago, this is the first problem I've had and I don't have contact information of the previous owners (not that they'd care by now I suspect!).

It is quite an old shower. Gainsborough ENERGY 2000X (assuming 2.5kW) but I was hoping to last until the summer when I plan on getting a new bathroom (and hopefullly a new hot water pipe + mixer rather than Electric Shower).

Thanks again. I'll see what it's like over the next couple of days and make sure its definately the weather thats causing it.

 

[stem]

It will be a lot more than 2.5kW. Today they are usually between 8kW and 10kW. The original models back in the 1980's were 6kw or 7kw, but because of the lack of hot water they provided, models have slowly got larger and larger. Obviously the larger showers need higher rated cables, switch gear and overload protection.

 

[Lokolo]

It will be a lot more than 2.5kW. Today they are usually between 8kW and 10kW. The original models back in the 1980's were 6kw or 7kw, but because of the lack of hot water they provided, models have slowly got larger and larger. Obviously the larger showers need higher rated cables, switch gear and overload protection.

Sorry I meant 9.5kw, I was reading the 2 in 2000 whilst typing!

 

[seco services]

If your only getting reduce temp in the morning you have a flow/pressure issue.

 

[Lokolo]

If your only getting reduce temp in the morning you have a flow/pressure issue.

Yep, but surely my combi boiler would stop as well?

 

[SaladFingers]

If your only getting reduce temp in the morning you have a flow/pressure issue.

Yep, but surely my combi boiler would stop as well?

Not necessarily, they may have different flow requirements.

 

[Lokolo]

Ah right OK thanks.

Is there anyway you can test the pressure to confirm? Obviously getting a plumber out at 7am to test it can be irritating for both them and I!

 

[SaladFingers]

Ah right OK thanks.

Is there anyway you can test the pressure to confirm? Obviously getting a plumber out at 7am to test it can be irritating for both them and I!

Flow, not pressure.

 

[Lokolo]

Flow, not pressure.

Right. Is there anyway I can test the flow? I'm assuming a bucket and a stopwatch and put the shower head over the bucket?

 

[SaladFingers]

Flow, not pressure.

Right. Is there anyway I can test the flow? I'm assuming a bucket and a stopwatch and put the shower head over the bucket?

That's a good idea. Use a measuring jug. Count to ten and multiply the amount caught by 6 and that's your flow per minute.

 

[stem]

If your only getting reduce temp in the morning you have a flow/pressure issue.

More flow = cooler temperature, so if the flow is too high in the morning reduce the flow using the regulator on the shower. The heat output from an electric shower is fixed. In this case at 9.5 kW the only way to control the temperature is by varying the flow of water through it.

 

[SaladFingers]

If your only getting reduce temp in the morning you have a flow/pressure issue.

More flow = cooler temperature, so if the flow is too high in the morning reduce the flow using the regulator on the shower. The heat output from an electric shower is fixed. In this case at 9.5 kW the only way to control the temperature is by varying the flow of water through it.

But, if the flow is too low, a flow switch will switch off the heater, leaving the water cold.

 

[bhm1712]

My 10.8kw shower does the same on Very cold mornings - bear in mind that the towns water supply is about 5 degrees at the moment as opposed to the usual 12ish.