Jump to content
The mkiv Supra Owners Club

Domestic plumbing question


stevie_b

Recommended Posts

I'm thinking of getting a new high-water-pressure shower fitted. The plumbing in my house is low pressure, gravity fed, and the bathroom where the shower will be fitted is upstairs. The wall where the shower will be fitted is beside the airing cupboard where the pipes come down from the loft storage tank, and it's where the hot water cylinder is. Hence, both hot and cold pipes will feasibly reach the shower first before the WC, basin etc.

 

My questions are:

1) I've read on the web that some shower pumps (e.g. this one) require a Surrey Flange to be fitted to the hot water cylinder. Is this necessary even when the water supplies reach the shower unit first? The flange also purges air from the system, so maybe that in itself is a reason to fit one.

 

2) If I understand correctly, the Surrey Flange gives the shower pump it's own dedicated hot water supply from the cylinder. Should I also run a dedicated supply from the cold water tank in the loft, or would it be sufficient to tap into the existing cold water supply that runs down from the tank? Logically, I can't see any difference between running a new pipe from the tank, and T'-ing off from the existing pipe in the airing cupboard.

 

Any thoughts/comments welcome, especially from any plumbers on here. I'm no expert on domestic plumbing but I know a bit about it.

 

EDIT: looks like I'll need the flange, and a dedicated cold supply direct from the loft tank: http://www.diynot.com/forums/viewtopic.php?t=169355

 

Anyone else done this/got any thoughts?

Link to comment
Share on other sites

This is true Stevie. Your cylinder may only be rated to 0.8 bar and could (although unlikely) implode if you don't fit some kind of anti vacuum device on there. I boost water systems for a living and this seems to be your only possibility giving the layout that you have.

 

H.

Link to comment
Share on other sites

The main reason for the surrey / warix / essex flanges is to provide an air free hot water supply. Air in the water will cause the shower pump to 'hunt'

 

You shoud run a seperate cold water supply from the loft tank.

 

What size loft tank do you have? Ideally, you want a large one (a coffin type plastic tank is ideal) as it will use alot more water than before.

 

BTW, i'd ignore that forum as even on that one thread, I can see some utter cr@p being spouted.

 

Any idea on what shower you want yet? For simplicity, the Aqualisa quartz/axis ranges are excellent, and provide decent performance.

 

A brilliant setup would be an Aqualisa Aquavalve shower valve, with a 3 bar Stuart turner or Salamannder shower pump (along with big storage tanks) and Aqualisas Turbostream shower kit.

Link to comment
Share on other sites

Also Stevie, after re-reading your initial post. I would defo run a separate supply from the header tank if you can. The shower pump will draw the water when running and it's better not to interrupt the existing supply. You would then have dedicated supplies for both hot and cold to the shower.

 

H.

Link to comment
Share on other sites

That's great advice, many thanks H and j_jza80!

 

What size loft tank do you have? Ideally, you want a large one (a coffin type plastic tank is ideal) as it will use alot more water than before.

 

Any idea on what shower you want yet? For simplicity, the Aqualisa quartz/axis ranges are excellent, and provide decent performance.

I've actually bought a thermostatic mixer shower from Homebase with 2 heads (one fixed, one flexible): I can't remember the make (it's not Mira or Triton, could be Bristan) and I was going to pump it using the 1.5 bar pump I linked to in my first post. It'll only have light occasional use. Some of the systems with valves mounted flush into the wall look incredibly smart, but as always price is a factor and the mixer showers with built-in valves seem to offer good value for money. Please do say if you don't think this'll work.

 

The cold water tank is "fairly big" cylindrical plastic one. I'd struggle to fit a bigger one due to the dimensions/trusses in the loft. Is there a minimum size you'd recommend for a 2 bed house?

 

I've heard the Essex flange is far easier to acquire than the Surrey flange, often for little more than the price of a kebab.

Fnaar!

Link to comment
Share on other sites

That's great advice, many thanks H and j_jza80!

 

 

I've actually bought a thermostatic mixer shower from Homebase with 2 heads (one fixed, one flexible): I can't remember the make (it's not Mira or Triton, could be Bristan) and I was going to pump it using the 1.5 bar pump I linked to in my first post. It'll only have light occasional use. Some of the systems with valves mounted flush into the wall look incredibly smart, but as always price is a factor and the mixer showers with built-in valves seem to offer good value for money. Please do say if you don't think this'll work.

 

The cold water tank is "fairly big" cylindrical plastic one. I'd struggle to fit a bigger one due to the dimensions/trusses in the loft. Is there a minimum size you'd recommend for a 2 bed house?

 

 

Fnaar!

 

I'd say minimum you'd want a 25 gal tank for a 2 bed. Depends on usage though. Your shower may flow as much as 20 litres per minute! (although it's probably more like 15, but remember this is hot and cold mixed)

 

Bristan showers are prefectly good, if you're on a budget then they're a very good compromise. A 1.5 bar pump will give you a good shower, and should be well suited to the shower you've chosen. They usually need a minimum of 1 bar.

Link to comment
Share on other sites

Stevie, what are the dimensions of the tank you currently have? A 25 gallon is just over 110 litres (nominal) after fitting ball valves and overflows I would imagine you would have about 80 litres of water to play with. Plus you will also be topping up the cold as you use the shower. I imagine you also have about 80 - 100 litres in the hot water cylinder so you should have plenty to serve one shower occasionally.

 

Give me the dimensions of the existing and I'll tell you what you have got to play with.

 

We have a Bristan at home and it has lasted a good 8 years or so without any problems.

 

H.

Link to comment
Share on other sites

My job is showers of all sorts.

You don't need any fancy valve and as j_jza80 said it's just to stop air being dragged through.

This is easily solved but fitting a T-piece facing downwards or taking off from any hot pipe going down.

I work on about 50 installations a week and in the last five years have never seen any ill effects to the cylinders.

My install is similar to yours but the hot is the first draw off before any other outlets and the cold is a dedicated feed. Fit isolation valves as this will make like simple if any repair or maintenance is needed.

The manufactures of the units should have a technical data sheet of the product on their websites

Link to comment
Share on other sites

My job is showers of all sorts.

You don't need any fancy valve and as j_jza80 said it's just to stop air being dragged through.

This is easily solved but fitting a T-piece facing downwards or taking off from any hot pipe going down.

I work on about 50 installations a week and in the last five years have never seen any ill effects to the cylinders.

My install is similar to yours but the hot is the first draw off before any other outlets and the cold is a dedicated feed. Fit isolation valves as this will make like simple if any repair or maintenance is needed.

The manufactures of the units should have a technical data sheet of the product on their websites

 

The reason to fit a flange is not to protect the cylinder, it's to protect the shower pump from hunting, which can potentially damage the pump (not only that, it's very annoying having the pump going on and off on a regular basis). Any shower pump should be supplied by dedicated pipework.

Link to comment
Share on other sites

I've finally pulled my finger out and looked up in the loft: my cold water header tank is 50 gallons, so that should be plenty hopefully. I imagine the hot water cylinder's capacity could be a limiting factor unless I like cold showers: it looks a decent size but I imagine it gets used up quickly.

Link to comment
Share on other sites

Guest hamiltonsupra

my tuppence worth.............

 

double check the shower you have bought is suitable for higher pressures firstly

 

Also by imagining your domestic set up i would try fitting the shower direcly to the pipework there minus the pump (ie teed off from hot supply from cylinder and cold feed from tank) in your tank cupboard

 

You may find when the shower is up and running you are well satisfied with the performance (and have saved a shed load of money)- if not it is easy enough to then cut the pump in at a later date to the connections you have prev made (though a seperate cold tank is advisable if using pump)

 

If your existing shower is electric or very old TMV type you will notice a fair pressure / flow difference without need of pump and associated plumbing and electics

 

Hope this doesnt add confusion but may save you money and install hassle

Link to comment
Share on other sites

my tuppence worth.............

 

double check the shower you have bought is suitable for higher pressures firstly

 

Also by imagining your domestic set up i would try fitting the shower direcly to the pipework there minus the pump (ie teed off from hot supply from cylinder and cold feed from tank) in your tank cupboard

 

You may find when the shower is up and running you are well satisfied with the performance (and have saved a shed load of money)- if not it is easy enough to then cut the pump in at a later date to the connections you have prev made (though a seperate cold tank is advisable if using pump)

 

If your existing shower is electric or very old TMV type you will notice a fair pressure / flow difference without need of pump and associated plumbing and electics

 

Hope this doesnt add confusion but may save you money and install hassle

 

I very much doubt that will work. He's bought a shower with both a fixed and flexible head. These almost always require at least 1 bar, if not 1.5 bar of pressure to work. He's not going to get that from a gravity system (unless the bottom of the tanks happen to be 10-15 meters above the shower head, which I very much doubt)

Link to comment
Share on other sites

Guest hamiltonsupra

fair comment if two heads can be used at same time........hard to say for sure when exact model is unclear - my point is sometimes these domestic installs can be over engineered and sometimes simpler is better - also flow rate on a shower can be as good or better overall than pressure (again circumstance dependant)

Link to comment
Share on other sites

fair comment if two heads can be used at same time........hard to say for sure when exact model is unclear - my point is sometimes these domestic installs can be over engineered and sometimes simpler is better - also flow rate on a shower can be as good or better overall than pressure (again circumstance dependant)

 

Depends how you likes your showers :D but if flow rates and/or pressure don't meet the minimum requirements, the showers usually lousy.

Link to comment
Share on other sites

The reason to fit a flange is not to protect the cylinder, it's to protect the shower pump from hunting, which can potentially damage the pump (not only that, it's very annoying having the pump going on and off on a regular basis). Any shower pump should be supplied by dedicated pipework.

 

As i said in my post - to stop air being dragged through.

Link to comment
Share on other sites

Christ, at last.

I was wondering whether j_jza80's reply was being doubly subtle.

 

Your comment did kinda whoosh over his head, but he was being sincere, at least.

 

A very amusing one liner it was too. :)

 

Sorry, it was supposed to be a double edged sword of knowledge/humour, but it was a little bit too subtle :D

 

I'll try and make up for it, with a bit more plumbing humour:

 

 

A Sam fox:

image

 

A John Holmes:

image

 

An emtee cock:

image

 

a Bleed nipple:

image

 

:D

Link to comment
Share on other sites

Is it easy to boost pressure? I moved from an old terrace where the water from the shower could strip the skin from your back (lovely) to a newish house where one shower is hardly useable and the other (power shower) is better but not good enough. It drives me and the wife mad. How much was something Like that cost?

Link to comment
Share on other sites

Is it easy to boost pressure? I moved from an old terrace where the water from the shower could strip the skin from your back (lovely) to a newish house where one shower is hardly useable and the other (power shower) is better but not good enough. It drives me and the wife mad. How much was something Like that cost?

 

Can you give me a quick run down on the current system in the house?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.