Help and advice on replacement boiler and system.

[Mcpman]

Hi,
Any help, advice or personal experience appreciated.

We are supplied by a lead pipe but on a shared supply. I am about house 4 out of a run of 6 or 7. When tested by Affinity Water no other houses seemed to be drawing water. If you were to run a hose and another house draws water the pressure drops to almost a trickle then builds up again.

Affinity Water Test.

Pressure at Outside tap = 2bar

Flow at outside tap = 13 litres per min

Flow at kitchen tap = 11 litres per min



Current water system consists of a cold water tank in loft and copper hot water cylinder in 1st floor bathroom. Cold water tank feeds bath,toilet,sink. All cold water downstairs that’s toilet,hand basin, garden tap and kitchen sink are fed by mains water. All hot is fed from hot water cylinder.



Heating.

There are 7 radiators fed from a separate radiator cold feed tank in loft. The pump is in the airing cupboard connected to cylinder and water system using a three port motorised valve. The boiler is a 29 year old Bali Solo power flue and the overheat cuts out when it wants. It has always been temperamental like this but has got worse.There is a gate vale on some 15mm pipe work between the flow and return to provide bypass.



Bathroom.



The bath has a set of mixer taps with shower hose and head. As explained before this is fed from copper cylinder for hot and cold water tank in loft. The pressure was appalling so I fitted a Stuart hot and cold shower pump under bath and this gives a lovely shower. One you have showered it seems to take a fair while for the cold and hot cylinder to complete re filling.





We don’t mind if we replace bath for large shower cubical and have to reconfigure bathroom we just want to achieve a nice pressure that provides a reasonable shower that does not result in pressure reduction or temperature difference when other houses draw water. (Also not keen on electric power shower fed by mains as we have also experienced flow drops when other taps turned on)



I have been looking at replacing the boiler and am now confused which would be the best option.

1. Combi boiler advantage no cold, hot water or heating tanks.( possible poor pressure and believe you can’t use pump on shower.

1. Replace with similar boiler and keep existing setup however water pressure in bathroom fed by cold tank is still not the best hence the pump under bath.

During my re search I have contacted water board for new water main out of the question at £5000.

Looked at mains pressure accumulator tanks that fit in kitchen cupboard. With additional ones able to be fitted in bathroom or loft. But would this supply enough flow for shower?



Pressurised hot water tanks but looked quite large.



Can anyone suggest a solution that will guarantee consistent water pressure and offer the best boiler choice along with a reasonable shower pressure.



I do not want to be in a situation where I go for a combi boiler which provides poor water pressure performance and then be bolting in additional things to try and resolve. Would like to make the right choice from the beginning especially as most of the pipes are under the kitchen floor so means removing some of the units. This will need to be done anyway as I also believe the gas to new boilers now needs to be 22mm which stops under the kitchen floor where it T’s off to the cooker and boiler in 15mm runs.



Obviously budget is important so not interested in mega expensive shower solutions that take your skin off and don’t want to spend 1hour in shower wit hot water but one that provides a reasonable normal performance with good pressure.

Appreciate any advice and possible solutions.

Many Thanks
Les

 

[gmartine]

I only skim read your post (best to keep it short if you want folks to respond) so I may have missed something but it appears you're going around the houses while also sitting on the answer(s).

It seems you have a satisfactory system except for the boiler itself which is begining to malfunction, replacing like for like should also improve the cylinder recovery rate. Sealing the system (central heating side ) will also improve efficiency while also getting rid of the feed and expansion tank and associated pipe work. Also check with your engineer about using your existing gas supply in 15mm, it may be sufficient for a small/med heat only boiler.

 

[Ric2013]

Firstly, buy Monument Tools Mains Water Pressure Test Gauge - https://www.NoLinkingToThis/p/monument-tools-mains-water-pressure-test-gauge/82412 , fit to your outside tap and then you can check your pressure at various times. You might find it often reduces to less than 0.7 bar at certain times of day, which seems to be the limit of acceptability. If so, argue harder with your water company. There may be issues with your mains other than the fact that they are shared.

Agree that a combi boiler would be unsuitable if you have flow issues.

What is the problem with the system you have except that your boiler overheats/thinks it overheats? Is it an easy repair? It might be!

The reason your bathroom cold is run from the cistern is that mixer taps require roughly equal pressures on hot and cold to work effectively, plus, possibly, your flow issues.

Assuming your system is in general good shape, I'd consider a whole house pump on your hot pipe from water cylinder, and another on the cold from your cistern. Cisterns can be large these days - 230 litres is often stated as the minimum for a cistern supplying both the cylinder and cold taps. Leave your kitchen and outside tap on the mains. Then fit a normal mixer shower.

I wonder what I'm missing?

 

[Mcpman]

I only skim read your post (best to keep it short if you want folks to respond) so I may have missed something but it appears you're going around the houses while also sitting on the answer(s).

It seems you have a satisfactory system except for the boiler itself which is begining to malfunction, replacing like for like should also improve the cylinder recovery rate. Sealing the system (central heating side ) will also improve efficiency while also getting rid of the feed and expansion tank and associated pipe work. Also check with your engineer about using your existing gas supply in 15mm, it may be sufficient for a small/med heat only boiler.

Hi gmartine,
I have my heating engineer popping round again. He was steering me to a combi so All the tanks could be removed as he said the modern boiler has pump and everything built into it which would mean creating a bigger space Removing the airing cupboard to re configure bathroom Layout With walk in shower however because of The poor water flow and pressure at times I think I will now look to the option you suggested and see what he comes up with. I think he also suggested the combi because removing airing cupboard would allow easier figment of shower Cubical as the other end of bath has soil pipe going through wall but thinking about it a false wall there in front of soil pipe would allow space behind for hiding shower pipes And servicing etc.
Many thanks for your reply and suggestion.

 

[gmartine]

Well you mentioned it but I think you were looking for confirmation to go against your plumbers advice which in this case I would especially with such poor pressure and flow and without the expense of upgrading the mains.

If the HW cylinder is of a similar age to your boiler consider replacing and upgrading that too as when a new boiler is suddenly paired with an elderly cylinder it can fail not to long after. Difficult to say exactly why that happens but a new boiler is able generate much higher temperature flow more readily and that may be enough to provoke a material failure in the coil of an old cylinder.

 

[Mcpman]

Hi,
Well the heating engineer popped round yesterday as he is a mate. That is why I wanted some extra opinions because I wanted to make sure I made the right decision. My neighbours have combi boilers on the same water main and although they are happy I must say their showers are pretty poor compared to mine with the pump. Weighing up everything along with your advice I showed him the shower working and said I want at least the same performance or better. I have decided to go for an ATAG i15s system boiler with A new rapid recovery cylinder. He is going to remove the heating header tank same as you suggested. He is also going to remove airing cupboard Cylinder in bathroom and respite new one in the hallway downstairs. He will then build a false wall to hide pipes where old Cylinder was to house a new mixer shower along with new walk-in shower 1400x900, toilet and Washbasin. He is going to use the existing shower pump and re site it and put all of the Bathroom on it shower, sink And also the toilet which is fed from cold water tank. He will power flush system and fit the new boiler. He also said he would put another pump on mains water Supply and re tile the new wall and where the bath was. I will only have to buy the tiles. The whole project should come to no more than £5300 including tiles When completed which I think is very reasonable as it has got to be a weeks work At least.

i haven’t bothered with another quote as my friend Is still building his new business having decided to go it alone 2 years ago and I have seen how expensive it is the cost of a van alone is enough to put you off plus whenever I have called him wether for a family member or friend He has always popped round next day. In fact he popped round one winter and cleaned the pilot on my boiler as it was blocked and not igniting and he didn’t charge me.

The ATAG boiler are not the cheapest and I know a lot of engineers don’t like them and prefer Worster Bosch but they are extremely well built with 10 year guarantee and lifetime guarantee on the stainless steel heat exchanger. My friend used to work for BG before starting up on his own so is well conversed on all makes and indeed fits what ever the customer wants to accommodate their budget but having researched a few boilers and as he is an ATAG installer I was happy to go for it.

Many thanks for your advice. It was really helpful and allowed me to choose what I now believe is the best option for us.

 

[gmartine]

That seems like a very good price, that'll be a vented cylinder then and you're keepng the cold water storage tank?

I ask that because rapid recovery cylinders are usually unvented and therefore reliant on decent mains pressure

 

[Ben-gee]

If he can do all that in a week I want him to come and work for me, I’ll be able to do nothing and earn lots of money!

 

[ShaunCorbs]

what pump is he fitting on the mains?