primatic to indirect tank,whats the difference?

[mikell]

My primatic has given up the ghost ,or more ,I have .
Been looking around and (please correct me)an indirect tank does basically the same job as a primatic, coil comes in with the central heating water passing through heats up the water ,or the element can heat it up from the tank.
If that is right ,what is the actual difference?
I have an overflow pipe coming out of the center top of my primatic ( im sure thats what it is anyway?)but dont have an extra plastic tank in the loft just the one that feeds the tank at present.
can I just change one for the other or do I need to alter anything?
tank is 900 x 400 (iv seen cutaways of indirect and it looks just like my primatic ).
Any guidance would be truly welcome gents thanks!

 

[wetshoes]

A primatic cylinder uses just the one tank in the loft.
If you change to an indirect cylinder you'll need to put an extra tank up there for feed & expansion of the central heating system.

 

[mikell]

Hi ,thanks,
Yes Iv just read up on that,had my loft converted this year so not too keen on starting up there with another tank!
I have seen a glendhill primatic for sale mine is 400mm this is 450mm do you think my pipes would couple up to this given the slight difference in size?

 

[dextrous]

I would be extremely surprised if changes to the pipework were not necessary.

 

[namsag]

So what is up with yours.

And the pipe coming out the top is the pipe to the hot taps and open vent

 

[mikell]

my emersion heater eelement has gone ( previously ages ago I had got the old element out or bits of it it had rusted off and fell to the bottom of the tank! ( I buckled the tank in the process but sealed a pinprick and replaced the element) .
Now this one had gone I cannot get it to budge and as the tank is already weak were it buckled previously , I cannot give it much force before the seam starts to go again. we use the emersion much more than the c/h boiler so this is what we need to do.
Its not viable to get a new boiler with all new rads and all new pipework when we can just hopefully sort out the cylinder.
ta again.

 

[namsag]

Why dont you use the boiler for hot water gas is cheaper than electric even on economy 7

 

[mikell]

We are doing that now ,but I think apart from habit ,it needs repairing anyway, but ( the wife deals with the bills I just work), we never used the c/h at all or the water for about a three month period last year and got a 80 pound bill which all we could put it down to was the pilot light!? we called out the gasman to check the meter and they said it was fine.
So we try to stay away from the gas.
point taken of course ,but it still needs repairing.

 

[londonboy]

Id hate to see your electric bill

 

[mikell]

its a monthly amount by d/d stays the same year round , bit like a fixed rate mortgage ,use more in the winter ,less in the summer,same amount you know where you are,....i think!

 

[Hugh Jaleak]

If there is room it may be possible, (subject to getting an overflow pipe to an external wall), to locate a F+E tank in the space above the cylinder. Only needs to be a small 10 gallon tank, with a 22mm vent from primary flow and 15mm cold feed to primary return.

This will allow you to fit an indirect cylinder rather than another primatic, unless there's any additional issues with the boiler and/or rads then you've no need to touch these. Fit a new cylinder, (I think you need to anyway!) then you can use the boiler to heat the water, it'll be far cheaper. Fit a new immersion and then keep it for emergency backup.

 

[mikell]

cheers guys
Hugh, there is deffo space above the present tank I boxed it in and can easily alter it to suit.
and this is located on an external wall .

so the only real big difference between primatic and indirct is the f+e tank ( apart from the air bubble in the primatic as opposed to the coil in the indirect?) with the f+e tank added ,thats the only thing that changes?
cheers.

 

[dextrous]

But the FE should be placed adjacent to the cold water tank and not above it.

 

[mikell]

cheers guys

Hugh, there is deffo space above the present tank I boxed it in and can easily alter it to suit.
and this is located on an external wall .

sorry should have read `deffo space above the present cylinder ,NOT tank! `
the cold water tank is up in the eves somewhere ,there is room above the cylinder ,on an external wall!
have just took measurments of my pipework in to cylinder so hopefully can find one to fit. if im lucky.

 

[Whitespirit66]

Back to your question 'primatic to indirect, what's the difference?'

A lot less aggro that's the difference. Primatics are clever but flawed. Ok so you need another tank in your loft. Small beer really.

Another thing to consider: with primatic, you are unable to use corrosion inhibitors in the system, because there is every likelihood that the rusty old water that runs through your rads can mix with the water in the immersion cylinder (if the air bubble that seperates the two systems should fail, etc). This 'orrible stuff thats in your rads can come out of your taps. Also, no corrosion inhibitor allowed means a corroding system = expensive!

Primatic - why did the inventors bother???