Low water pressure

[Inderpal]

Hello people

I need some advice had a combi boiler installed and since then the hot water pressure has reduced. The boiler is a main boiler!

Now if the kitchen hot water is on no hot water will come out of the bath or bathroom sink this wasn't the case before. The old combi boiler the hot water pressure was very powerful

Any ideas what could be causing this

 

[Harry Bloomfield]

Is you water stop tap partially closed? Might everyone in the area be on low pressure due to a fault? How is the pressure from your cold tap?

 

[Deleted member 267285]

Which model of Main, and what make/model was it’s predecessor?

 

[Inderpal]

The water stop which is under the staircase is open all the way.
The cold water has more pressure then the hot water.

The new boiler is a Main Combi Eco Elite 30kW Gas Boiler

Previous boiler was a, glow worm

 

[Deleted member 267285]

So you should be getting around 14 litres per minute on a 30 degree temperature rise. Would you say you’re not getting this? Was a pressure reducing valve fitted? Any other valves/restrictions fitted?

 

[Inderpal]

The water has decreased by a lot since the install of the new boiler. With the older boiler the pressure was soo much had go sometimes reduce it from the main stop cock

I have no idea what the engineer installed I have attached pics

 

[Deleted member 267285]

Doesn’t appear that anything is wrong in those photos. Could do with knowing the model of glow worm, if you know it to compare.

 

[Inderpal]

The previous boiler was a glow worm flexi com 24cx
I have noticed really early in the morning the water pressure is better

 

[Madrab]

Strange, your old boiler would deliver 10L/Min max @ 35deg rise but your new one should deliver 12L/Min at the same temp rise. The difference may be that your new boiler has a flow restrictor as part of the flow turbine, where your old one didn't.

Check the benchmark page in the manual, what does it say under HW delivery figures? If the mains pressure is higher in the morning then it could be a district effect, in other words, before everyone is up then the mains pressure is higher. Nothing unusual there.

To get a proper understanding though you need to confirm a few things. How hot is the water and how much in L/Min is being delivered by your new boiler at the moment. Time filling a bucket with hot water for exactly a minute. Check the temp and how much water there is.

A lot of combi boilers will struggle to supply more than one hot outlet at the same time but there is usually just a drop in flow and not a complete shut off.

 

[sbgasman]

It’s not easy to see from the photo but it looks like the cold supply is not turned fully on , it’s the second valve from the right and the black knob should point towards you

 

[Inderpal]

Do you mean this valve

 

[sbgasman]

Yes

 

[Inderpal]

It's fully open and pointing outwards

 

[sbgasman]

Sorry then you’re SOL