Hot water cylinder, bungalow loft??

[JohnJeff]

Hi

I have just purchased a bungalow in an area with no gas, it has electric storage heaters. I would like to put a hot water cylinder in the loft (currently in the hall) with header tank above but am being given conflicting advice. The hot water will serve bathroom with mixer shower and bath, kitchen. The ceiling height is 2.9m and the highest I can get the bottom of the cold water tank is 0.9m above the ceiling.
Can anyone advise on feasibility, pipe sizes etc.
Any advice much appreciated.

 

[stevetheplumber]

providing you can get the tank above the cylinder its ok remember to make the frame strong enough to support the tanks weight and spread the load onto at least one wall if not two

 

[SimonG]

If you have the mains cold water pressure and flow, how about a direct unvented cylinder?

 

[JohnJeff]

Thanks for advice, unfortunately the cold water pressure is not so good.
So as long as the bottom of the cold tank is just above the top of the hot water cylinder, things should work?

 

[fuzzy]

sounds like your struggling to get any head of pressure, maybe a small unvented would be best

 

[fuzzy]

or a combi boiler

 

[dontknowitall]

I'd much rather the cold storage in the loft with the hot water cylinder on the same level as the bathroom. Seems to work fine in other bungalows and also houses with bathrooms upstairs.

Alternatively (but not my choice), a combination boiler would suffice.

 

[JohnJeff]

The pressure at the hot taps is currently v low, i'm assuming the pipe sizes/design is wrong. There is no gas in the village and i'm not sure how oil prices are going to go so will leave the warm air heating system in for the time being.

 

[JohnJeff]

The new layout of the bungalow means it would be better to have the cylinder in the loft but this is where opinion seems to be divided. I assume that the pressure would be the same where ever the cylinder goes as its the cold tank which dictates this. But I have been told otherwise.

 

[SimonG]

Electric combi? Did one earlier this year, but again is dependant on mains flow and pressure.

 

[dontknowitall]

Oil, gas and electricity prices all rise over time - as we all know, especially over the last 3-4 years!!

I can't remember the exact figures but in roundish numbers, electricity uses one unit to heat one unit of water. Gas uses one unit to heat 2 units of water and oil can heat 4 units. Electricity has always been the most expensive way to heat (and probably the least environmently friendly), gas cheapest and oil lower than the middle of the two.

Cost of installation: Gas from around £2k and oil from around £3k.

If you're spending around £1,700 with electricity for heating I'd estimate it would be around £1,000 for gas and £1,200 for oil - but we don't know the size of the property so I'm guessing 3 bedroom. Obviously this does depend on the temperature the bungalow is kept at but if you're going to wander around in a t-shirt in winter then the cost will be much more!!

Over 10 years or so you'd definitely be better off installing gas or oil, imho.

 

[dontknowitall]

The new layout of the bungalow means it would be better to have the cylinder in the loft but this is where opinion seems to be divided. I assume that the pressure would be the same where ever the cylinder goes as its the cold tank which dictates this. But I have been told otherwise.

Much better pressure and flow with cold water storage on floor above hot water cylinder. The pressure of the cold pushes the hot water out of the top much more effectively when "head" is at least 2m as opposed to a few inches (if both tanks are on the same level). This is why most houses and bungalows are laid out in this fashion.

 

[Deleted member 25704]

Buy a stainless unvented, and put it in a cupboard, be safe. If you put your current arrangement in the loft, then who is sleeping underneath? Water at 60-80degrees centigrade or more above your head, while you sleep does not bode well for insomniacs.

 

[fuzzy]

The new layout of the bungalow means it would be better to have the cylinder in the loft but this is where opinion seems to be divided. I assume that the pressure would be the same where ever the cylinder goes as its the cold tank which dictates this. But I have been told otherwise.

the presure is determined by the height of the cold water cistern

 

[JohnJeff]

Thanks all, but the contrasting opinions I have been getting from plumbers is also being duplicated here. On the one hand I am told the pressure at the taps is relative to just the height of the cold tank but others say having the cylinder up in the loft will reduce the flow out of the hot tap? Has any one got a definitive answer?

 

[dontknowitall]

I've been trying to say (and others here have said as much) that having the cold cistern in the loft with hot cylinder on the floor below is the way to go - or install a combination boiler!!

 

[fuzzy]

dont think anyone has made the point of hwc in loft for pressure, more to do with space

dkia has the answer above

 

[Blackcatgas]

Yes it will "work" but you might be very disapointed with the flow from the shower, add a pump to the shower and Robert Mugabe is your uncle.

 

[JohnJeff]

Fuzzy, perhaps im thick, but dkia says it will work better if the cylinder is on the floor below and black cat gas says it will work? It sounds as if in the real world, the hwc needs to be a fair bit lower than the cold water tank, but I have just been reading a reply on another thread where it is suggested that the pressure will be increased by putting the cylinder in the loft.
I'm none the wiser.

 

[Blackcatgas]

Ive done a few like this, like I said, it will work. If your cylinder is on the floor from exp I would say that it would work better, the laws of pysics would sugest that it would be the same but it just works better like this.(Perhaps this is just anecdotal exp)
Your main concern will be the flow rate from your shower head which will be rubbish wether the cylinder is on the floor or in the roof.

 

[fuzzy]

Fuzzy, perhaps im thick, but dkia says it will work better if the cylinder is on the floor below and black cat gas says it will work? It sounds as if in the real world, the hwc needs to be a fair bit lower than the cold water tank, but I have just been reading a reply on another thread where it is suggested that the pressure will be increased by putting the cylinder in the loft.
I'm none the wiser.

the cyclinder could be on the moon or down in the deepest valley, the measurement is from CWSC (tank) to the outlet (tap)

if its 10 metres its 1 bar, if its 1 m its 0.1bar. you know what the measurement is, so you can work out the pressure, i suspect from what you say you will get about 2 metres max?

 

[Hardy1]

could get a LPG boiler, or electric, ask a local engineer or better ask the next door neighbour what they have lol.

 

[Megaflo-Experts]

the cyclinder could be on the moon or down in the deepest valley, the measurement is from CWSC (tank) to the outlet (tap)

Not strictly true!
The hot water cylinder cannot be above the cold water cistern. Remember the outlet is at the top of the cylinder, so water needs to flow into the cylinder before water can come out. If the cold water cistern (water level) and the hot water cylinder outlet pipe are at the same level, then no water will flow. Regardless of how many floors up it is, you won't get any water down below. It follows that if the cylinder is lowered slightly, then there will be water flow.
So, as dkia says, you're probably better off having the cylinder on the floor below.

 

[fuzzy]

Not strictly true!
The hot water cylinder cannot be above the cold water cistern. Remember the outlet is at the top of the cylinder, so water needs to flow into the cylinder before water can come out. If the cold water cistern (water level) and the hot water cylinder outlet pipe are at the same level, then no water will flow. Regardless of how many floors up it is, you won't get any water down below. It follows that if the cylinder is lowered slightly, then there will be water flow.
So, as dkia says, you're probably better off having the cylinder on the floor below.

Yes the cylinder cannot be above sorry, just trying to make the point that the distance between the top of the water level in the cistern and the outlet is key, if the cylinder was 1m below and the outlet 5 meters below the pressure would be 05.bar and if the cylinder was 4 meters below and the outlet 5 meters below it would still be 0.5 bar

 

[fuzzy]

having said that, if the cylinder wasnt vented above once filled even if above wouldnt the water stay in under atmospheric pressure? not that it would work as it needs to be vented but once filled im sure it would work

i know this is becoming science now!