reducing shower flow with combi boiler

[dragonfly101]

Since I got a combi boiler our mixer shower has been able to provide enormous hot water pressure and volume. This is too much though, and the bathroom gets really steamy and now I have mould growing on the ceiling. I've nagged my kids to have shorter and cooler showers, and also added an extractor, but still getting this problem.

I'm wondering now about getting a shower flow regulator like this one: https://www.amazon.co.uk/gp/product...84d-8286a3530ba1&pf_rd_r=T6FADGQE7DN9BMWNTDV2, but am concerned that I won't get any hot water at all. The combi boiler doesn't start heating water until a certain flow is reached, it's actually quite hard to get the shower running at the low flow it had when we had a hot water tank.

Another idea I had was getting cavity wall insulation as it's the north facing bathroom wall that is the one that's dripping after people have showers, and the mould is growing at the plasterboard that connects to it.

I could also add a flow restrictor on the hot pipe to the bath taps (where the shower comes from), but then it would take ages for the bath to fill (I still like to have baths).

Any thoughts?

 

[John D v2.0]

You can sometimes get flow restricting shower heads free from your water company. Ours sent a leaflet when we had a water meter fitted, and the one they sent us actually quite good. That would save water and gas.
Regarding your mould issue, you could alternatively get a better extractor fan, possibly insulate to remove thermal bridges, or improve the heating in the bathroom. I fitted one of those plinth heaters under the bath in ours. Final option would be a dehumidifier but that would really be a last resort.

 

[Madrab]

It's not about flow - reducing that won't really help as far as condensation is concerned, proper ventilation is needed and is really the only proper solution. The extractor size needs to be increased to get the airflow if the one you have doesn't help. Is there a window that opens?

 

[flameport]

Extractors only work if there is somewhere for air to enter the room, that hole or gap being at least the same size as the extractor outlet.

 

[dragonfly101]

thanks all, the condensation is a lot worse when my teenage sons have their 25 min.+ long showers (I wonder what they are doing when they are in the shower, ahem), than when I or my wife have our 10 min. showers. I do have a window in the bathroom, I'm not sure if it helps though because the cold draught from it chills the wall where the water condensates even more. I could experiment with the leaving the door open while showering and the window closed. It's frustrating because I only had the extractor fitted two months ago in the hope of fixing this problem.

The bathroom is definitely one of the colder rooms in the house, it only has an old heated towel rail connected to the central heating, not a proper radiator, and is north facing.

I ordered the flow restrictor on amazon, it was only £5 so will give it a go.

 

[Madrab]

You need a flow of air to draw the moist air away from the area where it condenses to outside. That would usually be a through draught, from say the door to the window or vice versa, or from the window to the extractor or door to extractor etc.