Using a pump with a Combination/Fortic cylinder

[Northernsky]

Hi all,
Long time lurker (and learner!) but could really use some advice.

I have a small flat that has a direct combination cylinder (110l hot, 40l cold) and I would like to install a pump to improve hot water pressure to the kitchen and bathroom taps and possibly bath. The cold taps are fed from the mains with good pressure and unfortunately I have an electric shower.

I know that using a pump for a shower would quickly empty the 40l cold tank but in your opinions would it be alright for kitchen/bathroom sinks? I only plan to install a small 1.5bar pump with a flow rate of 10l/m and obviously these taps would not be on for more than 4 minutes so the risk of sucking down air and damaging the pump seems low. Using it for the bath seems more risky due to the need for more water so I would welcome any opinions.

Many thanks,

 

[Breesey]

Don't do it.

 

[Northernsky]

Can you explain why?

 

[Breesey]

You've already done that yourself.

 

[Northernsky]

If you're referring to using it for a bath then point taken but I still don't see my kitchen/bathroom sinks using more than 40l of hot water at once and being in danger of running the cold tank dry. Do you disagree with this also? There is a place in the pipework where I could fit the pump to only function when water is drawn at these points.

Appreciate the advice.

 

[Breesey]

Apart from anything else a pump has to be fitted in a certain way - not just 'in' the existing pipe work.

You will not gain by fitting one and your existing system is not suitable for a pump.

Don't do it!

 

[Agile]

Get a proper sized feed tank and a conventional cylinder or an unvented cylinder.

Tony

 

[Breesey]

I get the impression that funds are not available for that!!

 

[Breesey]

deleted

 

[Northernsky]

Funds are available for an unvented tank and I have looked into it but I will be selling the property in a few months and don't think the benefit will be worth the cost. I also think there will be other issues with fitting one due to the layout of the building as pointed out by a plumber recently.

I was just looking for a cost effective solution to a minor problem - if it won't work then I will leave it as is.

In case it helps anyone who finds this thread later, someone at Salamander told me categorically that Fortic tanks can't be pumped whilst someone at Stuart Turner told me that it would be fine as long as I was mindful of the small cold water storage. Not sure why their opinions differ on this but personally I would trust the people who turned my money away.

Thanks all for your advice.

 

[Breesey]

"In case someone finds this thread later on"!! A quick look at the installation requirements of either of those pumps will tell you that your combi cylinder is not suitable for pumping.

 

[Northernsky]

Breesey, a quick search will show you that there are plenty of people who have asked about pumping fortic cylinders with some reporting success. There will be more people who have the same question in the future and unlike all the threads/pages I read before making this topic I am not looking to run a shower, just two taps, which is why I asked for opinions here and why it may help people in a similar situation. You have given your advice using as few words as possible so thank you but the question is now answered so there's no need for any other comments.

 

[Breesey]

There may well have been other people asking the question but if you look at your own "evidence" you will see that it is generally not advised.

What you decide to do is up to you but my advice, and that of others, as you have conveniently pointed out, is: don't do it.

So to other potential askers of the same question the advise would be the same: don't do it.

 

[algas]

I did this for a friend 1st change the ball valve for a 3/4" one for more cold water flow into the tank, I used a "whale" pump think it was 12v like they use on boats it was just for the kitchen as someone had fitted a monoblock tap only suitable for high pressure & did not work with the fortic in the flat.

Alan

 

[picasso]

Cant see a problem with fitting one of these on a fortic.

http://www.google.co.uk/url?sa=t&rc...yamqgFZBC5alb-Qs0954sNA&bvm=bv.43148975,d.d2k