Discussion
I have recently had a new bathroom installed and since then the hot water pressure in the bathroom is terrible. I would say it is an airlock and have read about the hose trick to sort it but i have mixer taps. Is there any other way to sort it apart from the hose on the cold connected to the hot tap?
Cheers
Cheers
http://www.the-sink-shop.com/taps_homepage.shtm
A guide to water pressure, critical when choosing your tap.
Generally speaking most properties in the UK have a cold water supply that is mains fed and usually High Pressure. The Hot Water pressure however can vary, it is dependent on the type of system used to generate and provide the Hot water to the Kitchen Tap.
The performance of any tap is determined by the type of tap, and it's compatibility with your plumbing supply. Most plumbing systems in the UK providing hot water, fall into two categories: Low/ Medium Pressure (Gravity Feed Supply), and High Pressure Systems.
The most common system in over 75% of UK homes is Gravity Feed Supply. This type of system has a high mains pressure, cold water supply connected direct to the kitchen tap, with a supply to a cold water storage/feed tank, (usually found in the loft space) the cold water is then fed by gravity from the tank to the hot water storage cylinder (usually found in an airing cupboard in the bedroom, bathroom or in a cupboard accessed from the landing) the hot water is usually generated by a boiler or in some cases a form of immersion heater. The hot water is stored in the cylinder and fed to the downstairs taps by gravity. The actual pressure of the gravity fed hot water is determined by the height of the bottom of the cold water storage/feed tank in relation to the height of the kitchen tap, the term for this is "head of water"
The higher the tank from the kitchen tap the greater the head of water, so the greater the pressure, ie. 1 metre head = .1 bar, 5 metres head = .5 bar, 10 metres head = 1 bar
The term Head of water means the vertical height from the kitchen tap to the underside of the cold water storage tank, The conversion from Bar to head is based on the assumption that the tap is situated directly in line below the storage tank. In reality this is very rarely the case and where long pipe runs occur across the property, from storage tank to the tap, the result is poor hot water performance.
To obtain sufficient pressure on a traditional gravity feed system to run an average High pressure tap with a 1 bar recommended minimum pressure you would have to have a 4/5 story building or 10 metres / (32.5 feet) head.
To run an average Medium/High pressure tap with a .5 bar recommended minimum pressure you would have to have a 3 story building or 5 metres / (16.25 feet) head. (Or a Booster Pump - see below)
A lot of new properties have High Pressure hot water systems fitted from new, mainly from combination boilers, they are also becoming more popular in the replacement market. Pressure systems provide a balanced and pressurized hot and cold water supply.
All taps will work with High Pressure hot water systems, but not necessarily with medium/low pressure Gravity feed supply, so it is important to check the specification of the tap before buying.
Please feel free to browse through the different manufacturers ranges of taps, if you’re not sure of the suitability of your preferred choice, please do not hesitate to ring us.
If you’re preferred tap has a high pressure requirement but you have a low pressure system, a booster pump can be fitted under the sink with a minimum amount of plumbing needed.
A guide to water pressure, critical when choosing your tap.
Generally speaking most properties in the UK have a cold water supply that is mains fed and usually High Pressure. The Hot Water pressure however can vary, it is dependent on the type of system used to generate and provide the Hot water to the Kitchen Tap.
The performance of any tap is determined by the type of tap, and it's compatibility with your plumbing supply. Most plumbing systems in the UK providing hot water, fall into two categories: Low/ Medium Pressure (Gravity Feed Supply), and High Pressure Systems.
The most common system in over 75% of UK homes is Gravity Feed Supply. This type of system has a high mains pressure, cold water supply connected direct to the kitchen tap, with a supply to a cold water storage/feed tank, (usually found in the loft space) the cold water is then fed by gravity from the tank to the hot water storage cylinder (usually found in an airing cupboard in the bedroom, bathroom or in a cupboard accessed from the landing) the hot water is usually generated by a boiler or in some cases a form of immersion heater. The hot water is stored in the cylinder and fed to the downstairs taps by gravity. The actual pressure of the gravity fed hot water is determined by the height of the bottom of the cold water storage/feed tank in relation to the height of the kitchen tap, the term for this is "head of water"
The higher the tank from the kitchen tap the greater the head of water, so the greater the pressure, ie. 1 metre head = .1 bar, 5 metres head = .5 bar, 10 metres head = 1 bar
The term Head of water means the vertical height from the kitchen tap to the underside of the cold water storage tank, The conversion from Bar to head is based on the assumption that the tap is situated directly in line below the storage tank. In reality this is very rarely the case and where long pipe runs occur across the property, from storage tank to the tap, the result is poor hot water performance.
To obtain sufficient pressure on a traditional gravity feed system to run an average High pressure tap with a 1 bar recommended minimum pressure you would have to have a 4/5 story building or 10 metres / (32.5 feet) head.
To run an average Medium/High pressure tap with a .5 bar recommended minimum pressure you would have to have a 3 story building or 5 metres / (16.25 feet) head. (Or a Booster Pump - see below)
A lot of new properties have High Pressure hot water systems fitted from new, mainly from combination boilers, they are also becoming more popular in the replacement market. Pressure systems provide a balanced and pressurized hot and cold water supply.
All taps will work with High Pressure hot water systems, but not necessarily with medium/low pressure Gravity feed supply, so it is important to check the specification of the tap before buying.
Please feel free to browse through the different manufacturers ranges of taps, if you’re not sure of the suitability of your preferred choice, please do not hesitate to ring us.
If you’re preferred tap has a high pressure requirement but you have a low pressure system, a booster pump can be fitted under the sink with a minimum amount of plumbing needed.
curtisl said:
I don't know actually. The toilet flush wasn't if that is anything to go by. I thought a tap was a tap. what would be the difference? The diameter of the pipe?
No the toilet ballvalve will be no indication. Taps vary tremendously and in my opinion problems with pressure requirement are really down to the 'fast-buck' bathroom suppliers. The vast majority of taps are made for continental Europe where unvented hot-water systems (and to some extent, the cheaper option, Combination boilers) are more widespread. Distributors in the UK have found it relatively easy to buy and import from any of the hundreds of tap manufacturers in the EU and beyond without really worrying about UK suitability. Taps with very small internal orifices and, worse, stupid little flexible hoses are making getting a decent taps for UK pressures and flow rates very difficult. I notice more and more taps are now being supplied with wider bore copper tails as well as the standard flexi-hoses, although I suspect that's due to the increasing number of failures and floods, to be honest!!
Thanks for your responses.
It looks like I will have to install a dual pump for the hot and cold water feeds to the bathroom but before I get the pump I want to make sure that the possible airlock is not to blame.
When I turn the tap on it splutters for a moment then resumes its piss poor pressure. Now if it is an airlock, would the pressure be down or would it just not work at all?
It looks like I will have to install a dual pump for the hot and cold water feeds to the bathroom but before I get the pump I want to make sure that the possible airlock is not to blame.
When I turn the tap on it splutters for a moment then resumes its piss poor pressure. Now if it is an airlock, would the pressure be down or would it just not work at all?
If you have a mixer tap, cover the outlet with the palm of your hand. Open first the hotwater and then the cold water. The pressure of the cold water should then flow up the hot water side (in reverse to normal flow). Do this for 30 seconds to 1 minute and this might clear the air lock.
Silver993tt said:
If you have a mixer tap, cover the outlet with the palm of your hand. Open first the hotwater and then the cold water. The pressure of the cold water should then flow up the hot water side (in reverse to normal flow). Do this for 30 seconds to 1 minute and this might clear the air lock.
Although it's actually not as simple as this......Festive Ferg said:
Silver993tt said:
If you have a mixer tap, cover the outlet with the palm of your hand. Open first the hotwater and then the cold water. The pressure of the cold water should then flow up the hot water side (in reverse to normal flow). Do this for 30 seconds to 1 minute and this might clear the air lock.
Although it's actually not as simple as this......
Duh, I thought you lived on the Moon and your air-lock was bust...
Can you find out what the pressure rating for your tap is? If you have a gravity-fed system and the tap is '1 Bar minimum' etc then change the tap (assuming everything else is OK).
Personally, I've found that a (hot) tap rated at 0.4 bar minimum is adequate downstairs in a gravity-fed two-storey house, but it wouldn't be much good upstairs or for running a bath.
Can you find out what the pressure rating for your tap is? If you have a gravity-fed system and the tap is '1 Bar minimum' etc then change the tap (assuming everything else is OK).
Personally, I've found that a (hot) tap rated at 0.4 bar minimum is adequate downstairs in a gravity-fed two-storey house, but it wouldn't be much good upstairs or for running a bath.
Edited by Simpo Two on Monday 28th December 17:36
Silver993tt said:
Festive Ferg said:
That's because your airlock was between the cylinder and tap, quite unusual, especially on an upstairs tap.
maybe so but it's a very simple no cost & quick option to try.Festive Ferg said:
Silver993tt said:
Festive Ferg said:
That's because your airlock was between the cylinder and tap, quite unusual, especially on an upstairs tap.
maybe so but it's a very simple no cost & quick option to try.Festive Ferg said:
Are other hot supplies affected?
Can you get to the pipework between the cylinder and rooftank?
Do you have a monobloc tap with removeable spout on the kitchen sink?
The other taps are fine, the pressure on the kitchen sink both hot and cold are good, good enough to blow the spout off the tap, saying that, the tap looks older than me.Can you get to the pipework between the cylinder and rooftank?
Do you have a monobloc tap with removeable spout on the kitchen sink?
I can get to the pipework between the the cylinder and the loft tank and just to note I am fairly unconfident when it comes to plumbing
I do have a monobloc tap in the kitchen and yes the tap does seem to semi remove, as i said, that happened all by itself soaking me and half the kitchen.
Before you start thinking I live in a poo hole or the house that Frank Spencer built, I have just moved in and undergoing some refurb works.
So are we saying that the hand on the tap is a bad idea?
Festive Ferg said:
30 seconds? No.
Unless the mixer is incorrectly plumbed.
Yes, waste time, when with the addition of a 22mm pushfit cap first you can do the job properly.
A little knowledge..........., eh?
No wonder I spend so much of my time getting people out of these sort of DIY f
k-ups.
What a load of rubbish. If I had listened to so called 'experts' in the trade, I would have forked out over £5000 to have a shower room refitted out, including all of the plumbing. I ended up doing it myself over about 4 weekends including all the recessed plumbing for the shower, sink unit, radiators, flooring ceiling (incl halogens), toilet, tiling (including mosaics, shower fitment. Not s single drop from any joint leaked out.Unless the mixer is incorrectly plumbed.
Yes, waste time, when with the addition of a 22mm pushfit cap first you can do the job properly.
A little knowledge..........., eh?
No wonder I spend so much of my time getting people out of these sort of DIY f
k-ups.Not only that, the 'experts' would have scratched/damaged the high quality shower fitments/glass that I purchased and commented on how it was 'unavoidable'.
Plumbing is very easy and it's always best to try the simple things first when you have a problem. What I suggested does take only 30 seconds, why would it take any more? I already said it worked for me on a number of occasions, so it is a method worth trying.
Also a few weeks ago replaced central heating pump, 5 radiators including all thermostatic valves. One of the easiest jobs I've done. How many £100's would that have cost getting some numb skull in only to be left with a bunch of leaks?
Got to say i agree with Silver993tt on this, i've just ripped a bathroom out and installed a wet room, done the floor (including gradient), new undeground waste, tiling (ceiling high), plumbing (about 60-70 metres from loft to rear of house), installed a shower pump.. everything works absolutely perfectly.
I had no leaks, only problem i had was me getting carried away having a shower and using all the hot water one day and consequently an air lock appeared and there was naff all pressure in the basin or shower, it was spluttering and coming out generally poo.. I removed the shower head put me finger over the end of the pipe, turned the shower on full and adjusted the temp up and down, then repeated that on the basin, turning that on full aswell, after 3 times on each one pressure was back. Just to add both the shower and basin tap are mixer types.
If I'd have got ripped off having the bathroom installed by someone in the first place how much would they have charged to fix that.. I've heard stories of people paying 10k for a loft/bathroom conversion then a month later a wet spot appears in the room below, all because some numpty didn't seal the shower tray properly (ended up costing about 2k to put right)..
I'm one for trying the simple suggestions first as there normally free. Some plumber will charge you an absolute fortune and could end up doing the finger over the end trick to fix it anyway.. Or come out with aload of bull and charge you even more..
Just remembered the finger over the end has worked twice the other time was when I had to isolate the water in the loft and empty the pipes to change the pump location. Turned the water back on and no pressure (not even enough to start the pump) bout 5 mins of changing between shower and basin all pressure was back..
I had no leaks, only problem i had was me getting carried away having a shower and using all the hot water one day and consequently an air lock appeared and there was naff all pressure in the basin or shower, it was spluttering and coming out generally poo.. I removed the shower head put me finger over the end of the pipe, turned the shower on full and adjusted the temp up and down, then repeated that on the basin, turning that on full aswell, after 3 times on each one pressure was back. Just to add both the shower and basin tap are mixer types.
If I'd have got ripped off having the bathroom installed by someone in the first place how much would they have charged to fix that.. I've heard stories of people paying 10k for a loft/bathroom conversion then a month later a wet spot appears in the room below, all because some numpty didn't seal the shower tray properly (ended up costing about 2k to put right)..
I'm one for trying the simple suggestions first as there normally free. Some plumber will charge you an absolute fortune and could end up doing the finger over the end trick to fix it anyway.. Or come out with aload of bull and charge you even more..
Just remembered the finger over the end has worked twice the other time was when I had to isolate the water in the loft and empty the pipes to change the pump location. Turned the water back on and no pressure (not even enough to start the pump) bout 5 mins of changing between shower and basin all pressure was back..
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