Pulsacoil taking 3 hours to fill a bath.

[Poita]

I don't turn on my boiler every day so I guess the water in it gets pretty cold.
But when I want to take a shower it I have to run it for one hour.
When I want to fill the bathtub I have to run it for a full three hours. Even if if run the boiler for 2.5 hours, the water turns cold before I can fill the tub.
Is this a normal running time for this much hot water or is there some adjustment I can make.
A friend says I can remove these two white caps (with mains power off) and turn a dial to make the water heat up quicker but I wanted to check here first.
Also, if I make some kind of adjustment to have the water heat quicker, does that make it less efficient - as in, it heats the same amount of water quicker but at a higher cost?
I have a boost button and my question about that is, does it cost the same to heat a certain amount of water only quicker or does it cost more per heated gallon etc?

 

[blup]

The lower of the two immersion heater elements has failed so only the top half of the tank is heating up ( hot water rises)

Blup

 

[Poita]

The lower of the two immersion heater elements has failed so only the top half of the tank is heating up ( hot water rises)

Blup

Is that a guess based on my description or is there something in the picture which shows it?

 

[JohnD]

I don't turn on my boiler every day so I guess the water in it gets pretty cold.
But when I want to take a shower it I have to run it for one hour.

It is a hot water thermal store not a boiler.

It is fitted with electric immersion heaters

I presume you do not have a gas boiler

A 3kW electric immersion heater raises cold water to hot at a rate of about 1 litre per minute. Due to thermal convection and stratification it will only heat the water at or above its own height.

It is normal to turn on the lower element, often with a timeswitch, to store enough heat for 100 litres or more which is sufficient for a bath. The upper element is turned on, often manually, when only small amounts of hot water are needed, or if the water heated the previous night has all been used up.

Your description suggests that the lower element is not working. This might be because it has failed, or it might be that there is a timeswitch only providing power at night and you did not switch on the element during the night. Or it might just be turned off. These are the usual reasons.

 

[JohnD]

A friend says I can remove these two white caps (with mains power off) and turn a dial to make the water heat up quicker but I wanted to check here first.

That is not true. Each immersion heater has a fixed output of 3kW. You cannot make it work faster.

You can run it until it reaches target temperature, and then it will turn off.

 

[JohnD]

I have a boost button and my question about that is, does it cost the same to heat a certain amount of water only quicker or does it cost more per heated gallon etc?

Cost per litre of hot water is the same.

There are no switches or other controls I can see in your pics. Photos would help.

Sometimes the boost button is wired to turn on the lower element, this is not usual.

 

[blup]

Is that a guess based on my description or is there something in the picture which shows it?

My tank has two immersion heaters and failed in the same way. This is a diy forum, you have to reach your own conclusions in the light of the various responses given. It's a good basis on which to call out a professional.

Blup

 

[JohnD]

BTW I don't know how big your bath is or how big your Pulsacoil is.

If an immersion heater provides enough heat for one litre of water per minute (which it does, approximately)

Then three hours would be enough for 180litres, which is more than an ordinary bath. Do you have a corner bath or something?

The insulation is very good, so there is not much to be saved by keeping your gledhill cold. You should lag those bare copper pipes, though.

 

[Poita]

BTW I don't know how big your bath is or how big your Pulsacoil is.

If an immersion heater provides enough heat for one litre of water per minute (which it does, approximately)

Then three hours would be enough for 180litres, which is more than an ordinary bath. Do you have a corner bath or something?

The insulation is very good, so there is not much to be saved by keeping your gledhill cold. You should lag those bare copper pipes, though.

Thanks, it's jus a normal sized bath.
And, I used to have it turned on and run for an hour ever morning then have enough hot water for a shower every day. But as I work from home and live alone I don't take a shower every day and with electricity prices skyrocketing I decided to turn off the three power mains switches below the timer so I only need to flip them and set the timer when I want a shower or bath. The rest of the time I was my dishes, face etc with cold water.

 

[JohnD]

Show us a pic of the switches and timer please

 

[Harry Bloomfield]

Cost per litre of hot water is the same.

Unless the OP has E7 or similar, and then E7 off -peak should be usually be set to power the lower element, to heat a full tank, at cheap rate. It seems the cheap rate system may not be working.

 

[JohnD]

If he has E7, I think he's turned it off.

 

[Poita]

Show us a pic of the switches and timer please

I don't have E7. It's the same cost day or night for my electricity.

The reason I turn the three switches off when I'm done with my shower or bath is that the timer has three timer settings. So I usually have the 2nd and 3rd one set to something like 'on at 8am and off at 8:01am'. I don't not how to just turn the 2nd and 3rd one off and I was concerned that if I set them to 'on at 8am and off at 8am' they might run for 24 hours. So I figured having them on for 1 minute won't waste power if I forget to turn off the three switches (which I do in fact forget about on in five times).

I take a shower or bath about twice a week to be honest. Just wash at the sink in cold water the rest of the time which I don't mind. So as I live alone and don't use the hot water heater every day, I figured running it for 3 hours to take a bath once a week and one hour to take a shower was ok. But I was quite surprised that it takes 3 hours to heat enough water for a bath and even then I can tell it goes cold by the time the bath is full.
I need to report to my landlord that something isn't right if you guys think that's the case.

Could you tell me what the best explanation is for him to pass it onto the heating engineer? Shall I just say that the hot water heater is taking too long so it's thought some part of it isn't functioning as it should?

Thanks for your friendly and helpful input by the way.

 

[Poita]

By the way, when the bath is full and the water from the tap has turned cold, I sometimes put the boost on and quick heat it up while I take a bath so I can shower off after my bath and it does heat the water up again.
I don't know if the boost uses the lower or upper element though so I don't know if this refutes the idea that the lower element is not working.

 

[JohnD]

The boost normally supplies the upper element.

By touching the plastic cap, you may be able to feel the extra heat of an element that is working