Hot water pump on a immersion heater.

[Macca2009]

Hi there just wondering if anyone can help me here. I have been asked by a customer to move a hot water immersion heater and tank into the loft, due to poor pressure in the bathroom. The immersion is currently situated upstairs in a cupboard next to the bathroom. I have found a position to site the cylinder and tank. The problem I need help with is that I wondering whether to fit a circulating pump on the hot flow from the cylinder. What sort of pump can I use and where would I fit it? Would it improve the flow rate and pressure of the hot water?

Thanks

Macca2009

 

[dontknowitall]

I'm going to have a stab at this, but not sure if I'm correct - hopefully on the right lines though.

Most houses with cold water storage have the cistern in the loft/attic with the hot water cylinder in the airing cupboard and this seems a tried and trusted system.

The cold water has a better pressure as it's high up in the house. If the cold water tank is on the first floor, moving the cold water storage cistern higher up to the roof space will create a much better pressure.

With the cold water tank in the loft (and hot water cylinder on the first floor) the hot water pressure will be approximately the same as the cold water since, as water is emptied from the hot water cylinder it is fed from the cold water storage under pressure (the drop from the loft to the first floor.)

Where you need a circulating pump for the hot water is if there is very long run of pipe from the hot water cylinder (more than say a couple of rooms). This run of pipe is called a dead leg as water cools in it. A ring of pipe from and to the hot water cylinder with a circulating pump will keep this water hot as the hot water will circulate constantly (more running costs). You tee off this pipe shortly before the bathroom.

All this should work well for a bath, standard mixer and electric showers. If you want a power shower (or car wash affair) you will probably require a shower pump to boost the system. Bare in mind though that with power showers your water and heating usage will rise dramatically and they are less economical than a large bath.

To save confusion, the immersion heater is in the hot water cylinder and is the part that heats the hot water via electricity (similar to a kettle.)

I hope a) I've got this right and b) it's helpful and c) I've not been patronising!

 

[migoplumber]

a, b +c okay by me !!

 

[plumbnuts]

Good answer.

Macca
Raise the cold water storage tank as stated and if not practicle, consider installing a whole house pump.
Steve

 

[Macca2009]

Cheers for that advice there, that does answer my question well. I think my customer has a standard mixer shower, so moving the tank will be sufficient. At least this will save the customer money, less work involved (I would have to add a pump and return leg otherwise) The only other quick question to confirm what work I will do is. The new position of the cold feed tank will be about 4/5 metres away from the cylinder in the loft (highest position) will this be ok for the presure still. The hot water presure is practically none existant in the shower, due to the shower head been about hight as cold tank in airing cupboard above cylinder

 

[dontknowitall]

Should be fine Macca. It's the height that's important. Check the water regs on installing a cold water storage cistern, as there are many rules on things like the lid, insulation, where the pipes exit, the floor support and so on. Not difficult but some is quite time consuming.

Good luck with it.

Migoplumber and Plumbnuts - thank you!! A relief I've got something right at long last!! I wasn't 100% sure but thought if I scribbled down my understanding then if I was wrong someone would hopefully correct me. Thank you again.

 

[Macca2009]

cheers much appreciated. I will consult the customer. I could move the lot into loft if they wanted, but it would a lot of work and big cost to them. might price myself out of work. Unlike some trades men out there, I actually want to help the customer and not just rob them.


cheers

 

[bobpape]

Lets hope your customer feels the same. (not just rob you)
Try and locate the cold supply tank over an internal wall and dont forget to put some
wood under it,

 

[migoplumber]

Lets hope your customer feels the same. (not just rob you)
Try and locate the cold supply tank over an internal wall and dont forget to put some
wood under it,

put some wood under it ??

a water storage cistern in any situation, requires adequate support, 1 litre of water weighs 1kg. if you have have 300 litres, then thats 300kg, it would require a well made reinforced platform.

if you want to give your customer maximum pressure, then your going to put that tank in the loft on 2 metre stilts. it requires a well built, strong, supporting framework.

dont forget plenty of insulation.

shaun

 

[bobpape]

Put some wood under it ???????

In fact I considered those words carefully,

Perhaps you did not recognise in my words the focus on weight, would not the young
or inexperianced plumber ask himself why place the tank over a party wall, would he
not extrapolate the issue and perhaps start to figure it out, would that little exercise
not help him to gain confidence,

Your more comprehensive instructions could be construed as misleading in the sense that they suggest to the inexperienced reader that there is nothing else to worry about when installing a tank in a loft where apparently no tank had ever been fitted,

Which leads one to think that perhaps the ceiling joists are not strong enough to support a tank, or perhaps you did and just cast the thought aside as being too much trouble to explain,

On the other hand you could have told him to stick it on top of a party wall taking comfort in the knowledge that he would have probably asked why.

 

[flat pack]

You need some idea of working with wood, distributions of loads ,
the high of expansion over tank, acess to ball valve.
you best as a local plumber/ mate for drawing of your big highchair base

 

[migoplumber]

sorry bob, didnt mean to sound patronizing,
i thought your answer was too short
now rereading my answer i see your point of view.

shaun