what boiler system if low mains water pressure

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Measuring the pressure at a point furthest from the incoming supply ( which may or not be the washing machine ) will then include the pressure drop created when water is flowing along the internal pipe work.
A moot point then regarding measuring @ washing machine valve.:rolleyes:
 
A moot point then regarding measuring @ washing machine valve.:rolleyes:

To be sure the measurement should be made a the point the boiler will be connected to the water supply with the flow that the boiler will take coming out of the pipe at that point and other taps flowing.

Or more simple and more secure is to not use a combi
 
The important thing to do is to quote each flow rate and see what they add up yo.

But more relevant is to take the flow which leaves 1.0 bar on the supply pipe!

Tony
 
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Just tell Tony to get on the bus with his mole and dig two holes and give him £500 and you will be sorted
 
Reading other old posts from people who have had the same predicament wouldn't it just be easier and simpler to have a cold water coffin in the eaves and keep the current set up. I'm not fussed about having pumps on the showers. Sometimes the simple things are the best? Due to having a loft conversion I just thought the cold water vented system had to go but if I could get a water tank in the eaves then think this could be the way to go.

Only problem I can see with this is how to get hot water to the sink in the loft bathroom as the hot water cylinder will be on the first floor. The shower could be pumped but is it possible to pump a tap? Any suggestions or keeping a vented system not a good idea?
 
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So been doing a bit of googling...as the outlets will be above the water tank a negative head scenario will be created so will need a negative head pump. Are these in terms of performance pretty much the same as positive head pumps? Just thinking out loud on this. Quite liking the idea of keeping the current set up and keeping a cold water tank and vented system with my loft conversion so would like opinions if viable and able to get decent hot water flow with pumps. Thanks.
 
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Sorry for the multiple posts...this has been a massive learning curve. Every time I think of a possible solution another problem comes up. So as long as the F&E tank (just learnt what this is) is above the highest rad then all good. No issues with The cold water tank being lower in the eaves? And the taps and shower can be powered by negative head pumps. My understanding correct? Have I missed anything? Thanks for you help.
 
Reading other old posts from people who have had the same predicament wouldn't it just be easier and simpler to have a cold water coffin in the eaves and keep the current set up.

Yes much easier and less trouble in the future. Non-vented cylinders were introduced for use in flats and situations where a loft tank was not possible. Many ( including it seems most installers ) believe that non-vented cylinders being more modern are automatically better than old fashioned vented cylinders

so will need a negative head pump.

Provided the pump is below the cylinder then gravity will ensure that there will be water in the pump when it is started ( if the pump is above the cylinder then the pump may have pump air to suck water up to it before it can start pumping water.

The only addition I would make is a level sensor in the cold water loft tank to shut off the pump(s) if they are drawing water faster than the mains can refill the tank and the tank is close to being empty. A luxury would be two sensors, one to warn people in the shower that the shower is about to stop so they can rinse down before the water stops.

With the tank(s) in the eves ensure there is good access for any maintainance ( and put a lid on to keep animals out :mrgreen: )
 
Mike both Tony & Bennygreen should be ignored. I don't want to be rude to Tony, but his advice on anything other than boilers is questionable. Bennygreen is the forum troll.

An unvented cylinder will give you the best performance at EVERY outlet.
Knowing Hertfordshire, I'd stick with my original advice. Upgrade your incoming mains supply.
 
Pullergas, I understand that mains upgrade and unvented system would provide pressurised hot water throughout the whole system but if I'm not bothered about pressurised water and happy using pumps for the bathroom and loft ensuite (and possibly loft taps) what are the other benefits from unvented system? As I understand it puts more stress on the pipes and costs more in addition to the mains upgrade cost. Is trying to keep the current set up and fit around a loft conversion such a bad idea? It will be a fair bit cheaper.
 
Granted you'll have an annual service cost on your unvented cylinder.
KISS!!
Pumps & all the associated will not as reliable & you'll reduce the amount of pipe work in your home too.
 
Bennygreen is the forum troll.

I (Bernard Green) have designed and installed the heating and hot water systems in the house I ( with my wife ) self built ( total DIY ) in 1981 and in the Grade II listed cottage that I am living in now. They work and provided all that was needed and some of the "unconventional" design features have been used by qualified heating engineers in other projects.

PullerGas installs systems as a means of earning a living. He doesn;t have to live in the houses after the install is completed. He is qualified and at times uses this to "prove" his opinion is correct and that he is also Qwallified to denigrate anyone who has a different opinion to his.

Sorry to turn this into a fight of words but PullerGas was the first to be unpleasant.
 
Mike both Tony & Bennygreen should be ignored. I don't want to be rude to Tony, but his advice on anything other than boilers is questionable. Bennygreen is the forum troll.

An unvented cylinder will give you the best performance at EVERY outlet.

Pullergas seems to be confused!

In this thread I have consistently recommended an unvented cylinder and, if necessary, an upgraded water supply.

Although you have the facilities to measure the dynamic flow rate, and I have explained to you what you need to do, you have not yet done it.

This is all very simple although the concept of dynamic flow is often not understood. As evidenced by the plumber you had who only measured the static and open pipe flow rate.

Tony
 
Tony, whilst I appreciate your advice you do have a habit of coming across as a bit patronising. When searching in this forum I found that you have a bit of history of this. I fully understand the need to test dynamic pressure and flow if I want an unvented system. I've done the pressure and will do flow later.

The topic has moved on and What I am now asking is the viability of keeping the vented system with the loft conversion if I want to keep costs down and to keep things simple and easier. As mentioned I'm not too fussed of having pressurised hot water from every tap. If pumps are a viable option in the loft shower room to provide pressure to shower and taps I'm more than happy going down that route.
 

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