Hello. I need some urgent advice re water pressure in an unvented system.
A few months back, I had my gravity fed system + boiler changed to an unvented cylinder + system boiler. The water pressure following the swap was incredible. We were originally talking about putting in a mains booster pump but seeing how good the pressure was without it, the plumber suggested we skip that step. He changed the incoming mains pipe within the property to 22mm and we left it at that. No digging, no moles, no blue pipe replacement or mains booster pumps.
Fast forward a few months. I’ve just had a loft conversion and water pressure in the loft bathroom is nowhere near what I have downstairs. The fitter has told me he used 22mm pipes up to a point but then changed to 15mm as that’s what’s needed to attach to showers and such. The fitter is saying the poor pressure is a result of not changing to blue pipes when we installed the unvented system and that a mains booster is pointless in this scenario. The original plumber says a mains booster might do the trick but a pump being a mechanical thing is more prone to faults so changing to blue pipes would be better long term but also much more intrusive and expensive.
I’m totally confused as to what to do and I have a few questions -
1. Is it normal for water pressure to drop in the loft despite having a new unvented system? The house has gone from having 1 bathroom to 2, pressure in the kitchen is still incredible.
2. Is there something my fitter’s overlooked that might be causing the problem with the pressure loss, such as pipe sizes or valves or some other technical aspect for example?
3. What is the best solution here? I’m tempted by the mains booster solution as it sounds like an easy, quick fix with no disruption to my drive but is it false economy?
Any help and advice would be much much appreciated! Thank you.
A few months back, I had my gravity fed system + boiler changed to an unvented cylinder + system boiler. The water pressure following the swap was incredible. We were originally talking about putting in a mains booster pump but seeing how good the pressure was without it, the plumber suggested we skip that step. He changed the incoming mains pipe within the property to 22mm and we left it at that. No digging, no moles, no blue pipe replacement or mains booster pumps.
Fast forward a few months. I’ve just had a loft conversion and water pressure in the loft bathroom is nowhere near what I have downstairs. The fitter has told me he used 22mm pipes up to a point but then changed to 15mm as that’s what’s needed to attach to showers and such. The fitter is saying the poor pressure is a result of not changing to blue pipes when we installed the unvented system and that a mains booster is pointless in this scenario. The original plumber says a mains booster might do the trick but a pump being a mechanical thing is more prone to faults so changing to blue pipes would be better long term but also much more intrusive and expensive.
I’m totally confused as to what to do and I have a few questions -
1. Is it normal for water pressure to drop in the loft despite having a new unvented system? The house has gone from having 1 bathroom to 2, pressure in the kitchen is still incredible.
2. Is there something my fitter’s overlooked that might be causing the problem with the pressure loss, such as pipe sizes or valves or some other technical aspect for example?
3. What is the best solution here? I’m tempted by the mains booster solution as it sounds like an easy, quick fix with no disruption to my drive but is it false economy?
Any help and advice would be much much appreciated! Thank you.
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