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Dg8

Sep 23, 2018
15
2
3
Hertfordshire
Member Type
DIY or Homeowner
Hi all,
My pressure reducing value has failed on my unvented cylinder, my plumber has already changed the potable expansion vessel and prv and cold water is still running through the tundish. I hate being the annoying Googling customer, but I've found a Honeywell pressure reducing value on Screwfix for about £40, but my plumber says you can't just use a 'generic' one and needs to be the 'correct one for my cylinder' priced at £120 +vat. Does that sound reasonable? It's just a standard cylinder that's installed in most Taylor wimpy houses. I just don't know if I should question it out not?
Thanks so much for your time
 
It has to be the correct one for the cylinder and you have to be G3 qualified. Also you need to remove your postcode from your profile.

Thanks for the profile spot. The plumber is G3. So everything seems about right?
Much better mate. On an open forum like this you need to be careful.
Thank you! So everything seems about right? My plumber is G3.
 
As long as he is G3 he will know the exact one to purchase. Let him do what he is trained to mate. Will be cheaper for you in the long run.
 
  • Agree
Reactions: chris watkins
Depends if the cylinder has a warranty and you want to keep in you have to use manufacturer spec parts

If you don't have a warranty then aslong as the valve is in spec then I would say it's fine
 
  • Agree
Reactions: Michael1960
Without wanting to
Depends if the cylinder has a warranty and you want to keep in you have to use manufacturer spec parts

If you don't have a warranty then aslong as the valve is in spec then I would say it's fine

Thanks. The cylinder is out of warranty. I was just wondering why if the cylinder requires 3 bar pressure, my mains is just over 6, it would it need a 'special' pressure reducing valve when any can be bolted into the 22mm cold feed and reduce the pressure to the recommended value. The one I was looking at was a decent make (Honeywell), is designed for unvented cylinders and has excellent reviews. It's the difference between £40 and £120+ for the part.
 
Without wanting to


Thanks. The cylinder is out of warranty. I was just wondering why if the cylinder requires 3 bar pressure, my mains is just over 6, it would it need a 'special' pressure reducing valve when any can be bolted into the 22mm cold feed and reduce the pressure to the recommended value. The one I was looking at was a decent make (Honeywell), is designed for unvented cylinders and has excellent reviews. It's the difference between £40 and £120+ for the part.
Why not, go for it stick your 6 bar one on in place & if the safety valves start discharging just cap em off.
Why do you think the Government made it a requirement under the Building Regulation Part G (3) that to work on these systems you need to have passed a competency test?
If anything went wrong you would not have a leg to stand on.
If it went to a flash steam explosion you would likely have no legs or arms or house.

Employ a pro, let them do the correct job, is it really worth £40????
 
Looks similar, but mine is not joined to the pressure release valve. I was considering
https://www.NoLinkingToThis/p/honeywell-pressure-reducing-valve-x/4671j
That is a dial up & not a fixed rated & very wrong!!!!
This is exactly my point, you don't understand what you are doing, what the requirements are & therefore the dangers.
 
That is a dial up & not a fixed rated & very wrong!!!!
This is exactly my point, you don't understand what you are doing, what the requirements are & therefore the dangers.
T
. I have no intention
That is a dial up & not a fixed rated & very wrong!!!!
This is exactly my point, you don't understand what you are doing, what the requirements are & therefore the dangers.
I have no intention of attempting any work myself. The dial-up Honeywell valve is approved for use on unvented cylinders. I may not have a G3 certificate, but I'm also not an idiot and do understand how system works
 
& with all due respect by your last statement you do not fully understand.

This is where I think your interest in what your Plumber is going to install goes beyond just that (interest).

I teach the Part G course so I think I know what I am talking about technically.
 
It should not be used as a replacement for a fixed & Maybe you should listen to those who do hold the G3 & not just read sale books.

Now if you want to fit the Honeywell go head & stop wasting our time, just bare two things in mind.
1. you will be breaking the Law
2. if things go wrong your house hold insurance will not payout.
 
  • Informative
Reactions: Scott_D
It should not be used as a replacement for a fixed & Maybe you should listen to those who do hold the G3 & not just read sale books.

Now if you want to fit the Honeywell go head & stop wasting our time, just bare two things in mind.
1. you will be breaking the Law
2. if things go wrong your house hold insurance will not payout.
Tell us what you really think mate.😀😀
 
  • Like
Reactions: chris watkins

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