Navien Combi Boilers
- Thread starter hard-work
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Well that remains to be seen. But, I agree that they can certainly try, and if they get the marketing right, they have a good chance.
WB and Vaillant aim direct at the end user and is why they are known to homeowners, if Navien follow suit, using the same methods to insert themselves firmly into the domestic market as a 'household brand' then installers will start to get asked about Navien, by their customers. If Navien do it right, with a 2 pronged approach to their campaign, said installers will have been wooed at the same time to explore the product.
Get the marketing right with a product that stands up and an appropriate price point and success should follow.
BUT... Installers still have a huge influence over customers and if not confident in the product will sway many away from it.
I often reason with my customers that far too much of the cost of a WB or Vaillant goes towards marketing, rather than R&D, when extolling the virtues of Intergas, because I prefer that latter over the former. They trust my experience and references are always there if required.
@hard-work, you know what many of us regulars do for a living, perhaps you could share with us what you do... as your posts infer that you are (or was) involved in the industry and it might make for a better discussion on some of these threads!
24 foot of 1/2 pipe as the claim can not supply 57KW no matter what appliance is connected at the other end
Best take that up with Navien.
The vid at 1 min 40 secs states, using the negative pressure gas valve 24 foot of 1/2" (15mm) pipe can be used supplying a 200,000 BTU (57kW) combi. Not available in the UK I believe. It may be.
The vid at 1 min 40 secs states, using the negative pressure gas valve 24 foot of 1/2" (15mm) pipe can be used supplying a 200,000 BTU (57kW) combi. Not available in the UK I believe. It may be.
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Could you provide that good reason, or is it forbidden to educate people.
I have already said why. As has another poster.
Where did you say why? A search for posts containing "negative" and posted by Dan Robinson does not find any explanation in this thread.
Bernard, I think he may mean this, BS 6891 – Specification for the installation and maintenance of low pressure gas installation pipework of up to 35mm:
https://www.installeronline.co.uk/wp-content/uploads/2013/04/Laying-down-the-rules.pdf
Which does not preclude a negative pressure gas valve as far as I can see.
https://www.installeronline.co.uk/wp-content/uploads/2013/04/Laying-down-the-rules.pdf
Which does not preclude a negative pressure gas valve as far as I can see.
It will certainly preclude sucking 57kw through a half inch pipe.
Unless it was threaded steel and equivalent length of no more than 1500mm.
Dannyboy the BS says no such thing.
Bernard, an installation with say 2m of 28mm from the meter and then 24 foot of 1/2" (15mm) pipe to the boiler's negative pressure gas valve. Negative pressure gas valves generally only open when the pressure at the outlet is lower than atmosphere (negative). A combustion fan creates the negative pressure, some get the pressure quite negative. As high pressure goes to low pressure and the greater the difference then the faster the gas moves, the gas down the 1/2" pipe will rush through the pipe faster. As the 28mm pipe is sized up for non-negative pressure, the velocity in this pipe will be as normal, not putting a negative pressure on the gas mains.
Gas moving through a small bore pipe fast can make a noise, which may not be nice in a domestic setup. Negative pressure gas valves are used in some commercial equipment. I would prefer to have a large bore pipe in a domestic setup, as there is no noise, and no negative pressure gas valve, which is another complexity which could go wrong, which few will understand, never mind know how to fix. But I can see how a negative pressure gas valve can get many out of jail.
The secret of the negative pressure gas valve is venturis. Venturis are/were used to get higher pressure in fire hoses to get pressure to the top of high ladders. Water pressure in, low, out high. Venturis are also used to lift water without using pumps. There is/was the Ideal Trevi boost venturi shower mixer valve for hot water low pressures.
Bernard, an installation with say 2m of 28mm from the meter and then 24 foot of 1/2" (15mm) pipe to the boiler's negative pressure gas valve. Negative pressure gas valves generally only open when the pressure at the outlet is lower than atmosphere (negative). A combustion fan creates the negative pressure, some get the pressure quite negative. As high pressure goes to low pressure and the greater the difference then the faster the gas moves, the gas down the 1/2" pipe will rush through the pipe faster. As the 28mm pipe is sized up for non-negative pressure, the velocity in this pipe will be as normal, not putting a negative pressure on the gas mains.
Gas moving through a small bore pipe fast can make a noise, which may not be nice in a domestic setup. Negative pressure gas valves are used in some commercial equipment. I would prefer to have a large bore pipe in a domestic setup, as there is no noise, and no negative pressure gas valve, which is another complexity which could go wrong, which few will understand, never mind know how to fix. But I can see how a negative pressure gas valve can get many out of jail.
The secret of the negative pressure gas valve is venturis. Venturis are/were used to get higher pressure in fire hoses to get pressure to the top of high ladders. Water pressure in, low, out high. Venturis are also used to lift water without using pumps. There is/was the Ideal Trevi boost venturi shower mixer valve for hot water low pressures.
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Can you provide a link to an example / explanation. ? A venturi is use to suck foam agent into the nozzle of a fire hose.
There are many types of water lifters.
http://info.cat.org.uk/questions/hydro/what-hydraulic-ram-pump/
You sort of got it. The venturi, which creates a negative pressure, instead of foam into the side, they put water, so water moved water to a greater pressure and higher.
http://info.cat.org.uk/questions/hydro/what-hydraulic-ram-pump/
You sort of got it. The venturi, which creates a negative pressure, instead of foam into the side, they put water, so water moved water to a greater pressure and higher.
D
Deleted member 221031
Never said Baxi made the block. I just said it’s the same. It is the same. End of
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