Damage new boiler by slightly increasing mains water pressure?

SubaruSeb

neilmcl said:

SubaruSeb said:

Thanks for your help so far.

The old boiler was a Saunier Duval, also a Combi like our new WB, and I believe it was considered overkill for the size of the (standard semi detached) house by everyone who saw it, so was that why we used to get a strong force from the shower even if someone flushed the toilet, which didn't render it a dribble?

If moving to a less powerful but therefore more suitable, efficient and cheaper to run WB means we'll never get as strong a gush from the shower head, we'll just accept that if you're all saying adjusting the street tap won't make any difference. Cheers.

What model of WB boiler do you have exactly?

Pretty sure it's a Worcester Bosch Greenstar 8000 Life Combi 30kW. Will check in a bit. Yes, it is. The old Saunier Duval Thermaclassic boiler was either 29.6kW or approx 25kW but no more.

GDB2222

If flushing the toilet is reducing the shower, it's nothing to do with the boiler. It's because you haven't got the stop tap in the pavement opened enough.  Go and open it, then the problem will go away.

The boiler installers needed to turn the water off to install the new boiler, and maybe they didn't open it fully afterwards?

Bendy_House

SubaruSeb said:

neilmcl said:

SubaruSeb said:

Thanks for your help so far.

The old boiler was a Saunier Duval, also a Combi like our new WB, and I believe it was considered overkill for the size of the (standard semi detached) house by everyone who saw it, so was that why we used to get a strong force from the shower even if someone flushed the toilet, which didn't render it a dribble?

If moving to a less powerful but therefore more suitable, efficient and cheaper to run WB means we'll never get as strong a gush from the shower head, we'll just accept that if you're all saying adjusting the street tap won't make any difference. Cheers.

What model of WB boiler do you have exactly?

Pretty sure it's a Worcester Bosch Greenstar 8000 Life Combi 30kW. Will check in a bit. Yes, it is. The old Saunier Duval Thermaclassic boiler was either 29.6kW or approx 25kW but no more.

Your new boiler is not the issue; that WB will be just as good, and quite likely better, than the ol' SD.

No, opening that street tap won't damage your boiler. Boilers, rads and pipework are designed to safely cope with 10bar, and in reality will handle more than this. Your incoming mains will be nowhere near that. Pressures over 4 bar (quite rare) are considered 'high' and should be tempered using a Pressure Reducing Valve.

So, by all means open the street S/C as that must certainly be affecting your flow, so it'll be no great surprise that an additional tap or loo being flushed is having a dramatic effect.

Bear in mind, tho', that opening another tap will have some effect, and almost certainly also did so with your old boiler?

If you have reason to suspect that your mains pressure and flow - with the street S/C fully open - is 'excessive', then have it checked (easy) and if necessary have a PRV installed in your house, just after the internal S/C - which, of course, you will replace at the same time :-)

SubaruSeb

GDB2222 said:

If flushing the toilet is reducing the shower, it's nothing to do with the boiler. It's because you haven't got the stop tap in the pavement opened enough.  Go and open it, then the problem will go away.

The boiler installers needed to turn the water off to install the new boiler, and maybe they didn't open it fully afterwards?

Brilliant - thank you for clarifying. This is our main issue, so I will adjust the stop tap in the pavement this afternoon and see if it improves things so loo flushes, the washing machine or other taps being on don't reduce the shower to a dribble - fingers crossed!

SubaruSeb

Bendy_House said:

SubaruSeb said:

neilmcl said:

SubaruSeb said:

Thanks for your help so far.

The old boiler was a Saunier Duval, also a Combi like our new WB, and I believe it was considered overkill for the size of the (standard semi detached) house by everyone who saw it, so was that why we used to get a strong force from the shower even if someone flushed the toilet, which didn't render it a dribble?

If moving to a less powerful but therefore more suitable, efficient and cheaper to run WB means we'll never get as strong a gush from the shower head, we'll just accept that if you're all saying adjusting the street tap won't make any difference. Cheers.

What model of WB boiler do you have exactly?

Pretty sure it's a Worcester Bosch Greenstar 8000 Life Combi 30kW. Will check in a bit. Yes, it is. The old Saunier Duval Thermaclassic boiler was either 29.6kW or approx 25kW but no more.

Your new boiler is not the issue; that WB will be just as good, and quite likely better, than the ol' SD.

No, opening that street tap won't damage your boiler. Boilers, rads and pipework are designed to safely cope with 10bar, and in reality will handle more than this. Your incoming mains will be nowhere near that. Pressures over 4 bar (quite rare) are considered 'high' and should be tempered using a Pressure Reducing Valve.

So, by all means open the street S/C as that must certainly be affecting your flow, so it'll be no great surprise that an additional tap or loo being flushed is having a dramatic effect.

Bear in mind, tho', that opening another tap will have some effect, and almost certainly also did so with your old boiler?

If you have reason to suspect that your mains pressure and flow - with the street S/C fully open - is 'excessive', then have it checked (easy) and if necessary have a PRV installed in your house, just after the internal S/C - which, of course, you will replace at the same time :-)

Excellent stuff - thank you! It's reassuring to know our new WB should be a good choice and that opening the street tap won't damage anything. You're right, even the old SD probably did suffer the odd moment where opening another tap or flushing the toilet reduced the shower flow a bit, but we definitely didn't notice it as much. We did, though, notice the boiler conking out twice a year, leaving us with cold showers, so good riddance to it!

plumb1_2

Might also be worth checking the filters in the shower as debris could have entered when the boiler swop happen 

SubaruSeb

plumb1_2 said:

Might also be worth checking the filters in the shower as debris could have entered when the boiler swop happen 

Thanks - good suggestion. It's just a basic bath mixer tap with shower hose attached, so I take it the filters are accessed by removing the hose?

NSG666

SubaruSeb said:

plumb1_2 said:

Might also be worth checking the filters in the shower as debris could have entered when the boiler swop happen 

Thanks - good suggestion. It's just a basic bath mixer tap with shower hose attached, so I take it the filters are accessed by removing the hose?

Open the stop tap fully and see what happens first as that might cure the problem. 30kw model should give a good hot water flow rate.

Another_Level

SubaruSeb said:

plumb1_2 said:

Might also be worth checking the filters in the shower as debris could have entered when the boiler swop happen 

Thanks - good suggestion. It's just a basic bath mixer tap with shower hose attached, so I take it the filters are accessed by removing the hose?

Oh heck, maybe its not a proper stand under unassisted solo use shower item ( advertising material is just that) .

I was thinking it was an existing shower mixer valve attached to the wall and the water flow has suddenly slowed after the new boiler install. 

Before installing the new gas boiler the installer should or maybe could have checked the hot & cold flow rates and  temperatures throughout the property   (not including any assisted shower attachments)

The installer would have flushed out any debris in the cold and hot water system, tick box done.

The new boiler may have a hot water a restrictor/limiter   fitted, its something to do with conservation and what others will add.

blah X 3

hope you get it sorted 

GDB2222

NSG666 said:

SubaruSeb said:

plumb1_2 said:

Might also be worth checking the filters in the shower as debris could have entered when the boiler swop happen 

Thanks - good suggestion. It's just a basic bath mixer tap with shower hose attached, so I take it the filters are accessed by removing the hose?

Open the stop tap fully and see what happens first as that might cure the problem. 30kw model should give a good hot water flow rate.

Personally, I would open the stop tap fully, then turn it back a quarter turn. It’s likely to be easier to turn off. Much easier.