Hello all.
This is my first time posting - I am not versed in plumbing or heating so please forgive any ignorance. In short, I am looking to move from a system boiler (with cold water tank in loft) to a combi boiler system. However I have poor pressure and flow rate, and would welcome suggestions. I have provided more detail on my circumstances below...
DETAIL:
I have a mid terraced property in West London (ground, first and loft). It has a system boiler located in a bed room cupboard, with a cold water tank in the loft. The property currently has 1 bathroom but are about to install an en-suite (shower only) in the loft. There are 9 radiators.
The street has poor pressure (Thames Water claim that they are supplying 2 bar). The property itself also has poor pressure, which Thames Water measured at 1.8 bar, which based on the discussions on this forum seems to me to be static pressure. The static flow rate is approximately 15 litres per minute, measured from the cold water tap in the garden (which connects direct to the mains). There is certainly a drop in the flow rate when I open the cold water tap in the kitchen sink. Note, this is all after having replaced old lead piping for a new MDPE 25mm pipe.
The heating (gas) bills are horrendous and I would ideally like to eliminate the cold water tank from the loft (also to make more room in the loft). This is bearing in mind that I would like the possibility to run two showers at the same time.
I was looking to move to a "high performance" combi boiler such as the Vaillant 837 (937 is too big) or a WB 37CDI. I had two local plumbers come visit the property, take readings and provide quotes. To my surprise, neither of these plumbers once mentioned the pressure or flow rates until I questioned them. One said that the Vaillant and WB "should" be ok (not "would" be ok); this does not provide much of a guarantee. The other suggested an unvented cylinder; this confused me as I had understood from reading topics on this forum that even an unvented cylinder needed a certain minimum amount of pressure to provide performance.
Although I want to free up space in the loft by removing the cold water tank, I thought that an accumulator with the combi may be a possible solution but again I understand that the accumulator does not create pressure so am not sure if this would work!?
I am therefore confused by the advice I have received (and from what I have read) and would welcome suggestions from this forum.
Many thanks in advance!
JT
This is my first time posting - I am not versed in plumbing or heating so please forgive any ignorance. In short, I am looking to move from a system boiler (with cold water tank in loft) to a combi boiler system. However I have poor pressure and flow rate, and would welcome suggestions. I have provided more detail on my circumstances below...
DETAIL:
I have a mid terraced property in West London (ground, first and loft). It has a system boiler located in a bed room cupboard, with a cold water tank in the loft. The property currently has 1 bathroom but are about to install an en-suite (shower only) in the loft. There are 9 radiators.
The street has poor pressure (Thames Water claim that they are supplying 2 bar). The property itself also has poor pressure, which Thames Water measured at 1.8 bar, which based on the discussions on this forum seems to me to be static pressure. The static flow rate is approximately 15 litres per minute, measured from the cold water tap in the garden (which connects direct to the mains). There is certainly a drop in the flow rate when I open the cold water tap in the kitchen sink. Note, this is all after having replaced old lead piping for a new MDPE 25mm pipe.
The heating (gas) bills are horrendous and I would ideally like to eliminate the cold water tank from the loft (also to make more room in the loft). This is bearing in mind that I would like the possibility to run two showers at the same time.
I was looking to move to a "high performance" combi boiler such as the Vaillant 837 (937 is too big) or a WB 37CDI. I had two local plumbers come visit the property, take readings and provide quotes. To my surprise, neither of these plumbers once mentioned the pressure or flow rates until I questioned them. One said that the Vaillant and WB "should" be ok (not "would" be ok); this does not provide much of a guarantee. The other suggested an unvented cylinder; this confused me as I had understood from reading topics on this forum that even an unvented cylinder needed a certain minimum amount of pressure to provide performance.
Although I want to free up space in the loft by removing the cold water tank, I thought that an accumulator with the combi may be a possible solution but again I understand that the accumulator does not create pressure so am not sure if this would work!?
I am therefore confused by the advice I have received (and from what I have read) and would welcome suggestions from this forum.
Many thanks in advance!
JT
