Not enough hot water to fill a bath!!

[ianhank]

Hello all, i have just had a new hot water cylinder fitted, it is a 123 litre 1130 x 400m direct heated. it is fitted with a 27" copper immersion heater element 3 kw at the top of the cylinder. i barely get a 1/4 full bath of hot water. before we had a 110 litre cylinder with an element fitted to the bottom of the tank which we could get a full bath from. the tank does state that the maximum element it can take is 900mm, what i would like to know is do i need to fit a longer element or is there something i am missing. any help would be much apreciated. Thank you

 

[Dan Robinson]

Have you checked the thermostat setting?

 

[ianhank]

its set to 65 Dan, same as the one that came out.

 

[JohnD]

So you have a 27" element. How tall is the cylinder?

You say you have set the (top-mounted) thermostat to the same temperature as the old (bottom-mounted) one used to be. You do know that hot water rises, so if the bottom of the cylinder was 60, the top will have been hotter? And if the top is now 60, the bottom will be colder?

 

[Dan Robinson]

Well, a 27" immersion is only heating the top HALF of the cylinder...

Start by fitting a longer immersion.

for a direct cylinder I wold be looking for a side entry bottom element anyway. But your are going to need 2.5 hours or so to heat the cylinder fully anyway.

 

[ianhank]

So you have a 27" element. How tall is the cylinder?

You say you have set the (top-mounted) thermostat to the same temperature as the old (bottom-mounted) one used to be. You do know that hot water rises, so if the bottom of the cylinder was 60, the top will have been hotter? And if the top is now 60, the bottom will be colder?

Its 1130 mm high
yes i do understand that heat rises and i do understand that the bottom would be cooler, i just thought that we would of got more from it. We went by recomendations of our plumber at what he thought would be best!

 

[xr4x4]

Where can u get a longer than a 27" immersion?

 

[ianhank]

Well, a 27" immersion is only heating the top HALF of the cylinder...

Start by fitting a longer immersion.

for a direct cylinder I wold be looking for a side entry bottom element anyway. But your are going to need 2.5 hours or so to heat the cylinder fully anyway.

Thanks Dan, will go for the longer immersion

 

[Dan Robinson]

Where can u get a longer than a 27" immersion?

Off the top of m head? dunno,.. don't fit many direct cylinders, and if I did , it wold have a bottom tapping for one.... top only is daft IMHO.

 

[JohnD]

very sad that you did not get a cylinder with a top and a bottom element. They are popular with people who have economy-7 type tariffs, as they let you fill up the whole cylinder at the cheap rate, and top up, if necessary, at the daytime rate.

 

[ianhank]

very sad that you did not get a cylinder with a top and a bottom element. They are popular with people who have economy-7 type tariffs, as they let you fill up the whole cylinder at the cheap rate, and top up, if necessary, at the daytime rate.

If only i had found this site first before getting a new tank !! oh well many thanks anyway. i have found a 36" immersion which is about 915 mm, the tank does state 900mm max

 

[JohnD]

see if you can get a dual-element ("sink and bath") immersion in that length, it means you can quickly heat a small amount of water with the short, folded element, if you need it (also cheaper to run when you are not planning a bath).

They are rather expensive

 

[ianhank]

see if you can get a dual-element ("sink and bath") immersion in that length, it means you can quickly heat a small amount of water with the short, folded element, if you need it (also cheaper to run when you are not planning a bath).

They are rather expensive

Thanks john, will look into it

 

[Nige F]

very sad that you did not get a cylinder with a top and a bottom element. They are popular with people who have economy-7 type tariffs, as they let you fill up the whole cylinder at the cheap rate, and top up, if necessary, at the daytime rate.

If only i had found this site first before getting a new tank !! oh well many thanks anyway. i have found a 36" immersion which is about 915 mm, the tank does state 900mm max

I would try the 915 one - 15mm is a small difference - if the immersion doesn`t touch anything you`ll be allright - that 900 measurement may be to allow for scale @ the bottom of the cylinder - and you aint got any yet

 

[cantaloup63]

I would try the 915 one - 15mm is a small difference -

15mm would make a big difference to my life