Hire a tradesperson!

Post your job for free and without obligation
More than 207832 connected tradespeople
Over 2335756 verified reviews

Ask a tradesperson

Question category:

Plumbing

Boiler Preasure

Anonymous user 19 March 2015 - 12.24 PM

Hi I have an vaillant eco tech plus 831 bolier about 4 years old. on the front digitial desplay, it displays 1.5 bar. We have had our water company come out today to test what is coming into the house. they tested from the outside tap and the result was over 20 leters per min (As it was flowing our of his cup) and for preasure it was 3 bar. So with this in mind, why is the combi showing 1.5 bar and not 3? Also, does that mean that when we are having a shower that the boiler is only giving 1.5 bar or do we get the full 3 bar preasure? any help would be great Michael

3 answers from MyBuilder tradespeople

Lewis Mason
Best answer
Lewis Mason
Rating: 5 out of 55592 reviews
Birmingham

The 1.5 bar reading displaying on your boiler shows the pressure of the water in your heating system, it has nothing to do with the pressure of your hot or cold water. The pressure of the heating system can be topped up via a filling loop, but you should not increase this to 3bar!! 1.5 is the desired pressure for a heating system. If you want to check the pressure of the water to your shower you will need a weir gauge/flow cup, just like the guy from the water company would have used, unscrew the shower head and turn it on, measuring the flow rate of the water that comes out. But just to clarify the pressure displayed on your boiler is for your central heating system and not your hot or cold water. Hope this helps

Answered

19 March 2015

Like

1

Anonymous user

Hi Micheal, The reading of 1.5 Bar, is the pressure in the sealed central heating loop, side of your boiler. and that is prefect. As your boiler is a combi boiler there is another section which heats the water on demand. The way this works, is that water is allowed in at a lower pressure to allow it time to heat as it passes through the boiler. This is why you have more pressure from your cold water tap than your hot. The water is allowed in, normally at 1Bar, which increases slightly due to expansion during heating, but you will not achieve 3Bar Hot water pressure without changing boiler and installing a Mega-Flow or similar hot water vessel. Regards Simon

Answered

19 March 2015

Like

0
Heat Central
Heat Central
Rating: 5 out of 55554 reviews
Bewdley

The dial on the boiler has nothing to do with the cold water pressure, it only shows the pressure in the radiators. Completely different pressures, the dial on the boiler changes when you top up the boiler via the filling loop.

Answered

19 March 2015

Like

0