attic rads with open vent system

[anthonytutton]

Hi all. First post so please be kind!

I am doing a loft conversion, and i would like to add 3 radiators in my attic. I have an open vent system. Am I right in assuming that i can add radiators at the same level as the expansion tank (as its in the attic) as the heating system is pumped?

Secondly, i have a cold water galv tank in my airing cupboard, for the hot water supply. I am adding a bathroom in my attic, and would like to get hot water up there for the shower, and sink. is there enough gravitational force, to get the hot water roughly 10 feet above the galv tank? Or am I looking at a new combi conversion to pump the water up there?

thanks in advance

 

[swidders]

Hi all. First post so please be kind!

I am doing a loft conversion, and i would like to add 3 radiators in my attic. I have an open vent system. Am I right in assuming that i can add radiators at the same level as the expansion tank (as its in the attic) as the heating system is pumped?

Nope - expansion tank should be at least 1m higher than top of highest radiator

Secondly, i have a cold water galv tank in my airing cupboard, for the hot water supply. I am adding a bathroom in my attic, and would like to get hot water up there for the shower, and sink. is there enough gravitational force, to get the hot water roughly 10 feet above the galv tank? Or am I looking at a new combi conversion to pump the water up there?

thanks in advance

On the whole, water likes to go downhill , not uphill. How can gravity force water upwards above itself? In any case, the water level of the cold water tank should be above the level of the water in the expansion tank to prevent possible contamination in the event of system failure.

On the whole I think you're looking at a combi!

 

[mogget]

is there enough gravitational force, to get the hot water roughly 10 feet above the galv tank

Gravity only works downwards, as Newton discovered - have you ever seen an apple floating upward?

I believe the feed and expansion tank has to be a minimum of one metre above the highest part of the central heating circuit.

 

[mogget]

On the whole I think you're looking at a combi!

Yup!

 

[swidders]

mogget - simultaneous again. People will start talking

 

[anthonytutton]

what i was thinking is that if my galv tank is full of water, then the weight of that water in a 2 foot x 3 foot tank should force water up, if its only a 15mm copper pipe? but thats why im asking lol. im no expert. thanks for all the quick replies

 

[seco services]

you are being serious.

if you want to use gravity how do you intend on getting the hot to feed higher than the storage tank ?

you can use a neg head pump.

 

[mogget]

I know, it's weird isn't it!

For the benefit of the OP - swidders and me often post at the same time, saying much the same thing. I think he must type a bit quicker than me though

 

[anthonytutton]

ok lol. I've been told. combi it is then?

 

[mogget]

what i was thinking is that if my galv tank is full of water, then the weight of that water in a 2 foot x 3 foot tank should force water up, if its only a 15mm copper pipe? but thats why im asking lol. im no expert. thanks for all the quick replies

Unfortunately for plumbers, water will find its own level, whether in a lake or a 15mm pipe. Otherwise we'd be able to get free fountains just by dipping a foot of pipe into a pond

 

[swidders]

Or am I looking at a new combi conversion to pump the water up there?

Er - water will be pumped through the central heating system, which will be a closed, pressurised system.

Hot water to the taps will rely on the mains water pressure supplied to the house and will not be pumped (not allowed to!!) - so you need to check that this will be adequate. In simple terms, if you stood outside, turned a hose on full and pointed it upwards, will the jet clear the top of the house? If yes, then you stand a fighting chance.

Either way, you will not have any water tanks of any description anywhere upstairs.

 

[mogget]

ok lol. I've been told. combi it is then?

I think that will be the easiest way of achieving what you require.

 

[mogget]

Or am I looking at a new combi conversion to pump the water up there?

The combi won't do any pumping itself, but will allow you to take advantage of the water company's pump

 

[anthonytutton]

so i need to ensure my incoming supply is tip top then?

 

[twgas]

I would suspect a combi may be one option, but others are possible. Do you not have a designer/architect/advisor to explain advantages and disadvantages of your various options?