How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Rick Ridley Your Own Question
Rick Ridley
Rick Ridley, UK Heating Engineer
Category: UK Plumbing
Satisfied Customers: 2708
Experience:  30 Years on the tools, now retired, Ex CORGI
Type Your UK Plumbing Question Here...
Rick Ridley is online now
A new question is answered every 9 seconds

how do i increase pressure in my boiler. System leak repaired

This answer was rated:

how do i increase pressure in my boiler. System leak repaired but can't get pressure back, so no hot water, Boiler checked and is fine.
Radiators won't fill either. I have opened all valves.
Hi I am Rick, UK Plumber, and I specialize on Boiler problems, you will have a filling loop usually near the boiler, this consists of a braided flexi hose with a tap at one or both ends, connect this hose and turn on both taps to fill the system, it may not be near the boiler, but it will be in a place that heating a mains pipes are together, depending on your boiler you could have a model that has a built in filling system, you may have a "key" to operate it or just a pair of taps under the boiler, but for more detailed info on this I would need the make and model of the boiler, regards Rick
Customer: replied 6 years ago.


There's a key. It's a worcester Greenstar 37cdi combi. I've opened that tap, water goes through but pressure guage doesn't move. Boiler has been checked and it's fine. Engineer said there was leak in system and it's been found and repaired.

OK are you sure that the key is fully home before you turn it, you are turning the valve to the left of the key? you should hear the water flow, if the pressure is increasing then water should come out of the radiator bleed points indicating this pressure, if that is the case then it is probable that the boiler pressure gauge/sensor is clogged up/faulty, Rick

Edited by Rick Ridley on 8/29/2010 at 8:47 AM EST
Customer: replied 6 years ago.
yes, i can hear the water running into the boiler. The engineer checked the pressure guage and said that it was fine. If I open the radiator blled point, nothing happens.
I added to my last post but maybe you did not see it, you are opening the valve to the left of the key, Rick
Customer: replied 6 years ago.

sorry, didn't see it!

yes i am.

If you are not able to bleed the rads it would suggest that nothing is going into the system or that the system is empty and needs more water that you have so far put in, was the system drained to cure the leak? Rick
Customer: replied 6 years ago.

yes, the system was drained. How long would it take roughly to fill the system? Also, should I open all the radiator valves at once? There are 3 floors. Does it fill from the bottom up?


many thanks

All the radiator valves should be open, continue filling until you get a reading a reading of around 2 bar on the gauge, then bleed the rads keeping an eye on the pressure, and topping up as required, although it sounds like a lot of water is flowing it is not that fast, and can take a while to fill, Rick
Customer: replied 6 years ago.

Thanks. I'm going to do that. I did try yesterday but I had the bleed valve open also.

Maybe i didn't try for long enough.

Can I just see how this goes or should I 'accept answer' and come back if nothing happens?

See how it goes, I will be about most of the day, off and on, wait to hear, Rick
Customer: replied 6 years ago.

sorry I'm not sure if I sent this so apologies if it's the second time.

I spent the day with the tap open and apart from the sound of water going into the upstairs radiator, nothing has happened. Pressure hasn't come back up and radiators haven't refilled. It can't take this long can it?

No, are you sure you have not got a leak some where, water is clearly going into the system, have you checked the pressure relief valve discharge point out side the house, Rick
Customer: replied 6 years ago.

nothing coming out of the overflow. No signs of water in the house so I think that only leave under the ground floor. I can't hear anything but it must be there.This much water would have shown up elsewhere.

It might be easier to ask a plumber to just put new pipe under the floor rather than lift the floor up.

If it has been running all day you will need your wellies for under the floor, hope you get it sorted soon, I know it is the obvious but is there a drain point under the floor that has not been done up, it would not be the first time a plumber has forgotten that, Rick
Rick Ridley and other UK Plumbing Specialists are ready to help you
Customer: replied 6 years ago.

I don't think so as it's been fine for a couple of years and would have shown up before. I hope the whole floor doesn't need to come up.

Many thanks for all your time today. I'll send this then hit the'accept' button.

Thanks again

Glad to have been of service, Rick

Related UK Plumbing Questions