HEP2O Piping Again

[Frankieboy]

Can someone just confirm before I buy all relevant bits, would a standard 22mm main pipe, with 15mm take-offs to taps etc be the way to go.

Would rather do it right first time than have to sort it out later.

Cheers

 

Also, what is the difference between "wavin" pipe inserts and normal ones and which should I use?

[Ark Right]

Hi Frank,

Think you are getting your systems confused.

Hot and cold domestic pipework, i.e. from the pump to and from calorifier , to shower, bathroom taps, galley taps etc need only be 15mm.

Its the heating systems i.e from stoves or boilers that need the bigger feed pipe and the smaller branches off, hope this helps

Cheers A

 

Sorry don't know about "wavin" inserts, just go for the Hep 20 ones

Edited May 22, 2011 by Ark Right

[Nickhlx]

Hi Frank,

Think you are getting your systems confused.

Hot and cold domestic pipework, i.e. from the pump to and from calorifier , to shower, bathroom taps, galley taps etc need only be 15mm.

Its the heating systems i.e from stoves or boilers that need the bigger feed pipe and the smaller branches off, hope this helps

Cheers A

 

Sorry don't know about "wavin" inserts, just go for the Hep 20 ones

 

 

I would echo that - the 22mm pipes for DHW are un-necessary as it will take longer to get the hot water from the tank and the odds are there will never be more than one tap on at once, so flow is not going to be an issue

 

Nick

[sharpness]

Also, what is the difference between "wavin" pipe inserts and normal ones and which should I use?

Wavin is a manufacturer. I cant remember if they are the parent company for OSMA or Hepworth, maybe even both.

 

Steve

[the grinch]

Hep2o has changed from the crappy grey rubbish that falls apart to a new white pipe and fittings the "wavin" inserts i'm not sure on but hep has a ridged insert that is designed to ensure you have pushed it home correctly.

buy a proper cutter as well as it will make life simple

avoid plastic within 1.5 metres of boiler and 2metres of a solid fuel stove as it cannot take that sort of heat abuse

[Ark Right]

Hep2o has changed from the crappy grey rubbish that falls apart to a new white pipe and fittings the "wavin" inserts i'm not sure on but hep has a ridged insert that is designed to ensure you have pushed it home correctly.

 

 

please tell me more

[the grinch]

please tell me more

 

what do you need to know?

 

the old grey fittings had a green grip ring that failed with some spectacular results

the new white fittings are more robust and the inserts are ridged as is the inside of the fittings when pushed together and twisted you can feel the ridges rumble.

[canaldrifter]

 

Its the heating systems i.e from stoves or boilers that need the bigger feed pipe and the smaller branches off, hope this helps

 

 

Usually, rule of thumb stated that 15mm pipework would supply three radiators adequately, any more would require 22mm pipework, up to the point where three rads were left on the circuit.

 

I can't think of any situation in a narrowboat where 22mm pipework would be necessary, unless it would be for gravity circulation from a solid fuel backboiler.

 

Tone

[Frankieboy]

Right, 15mm all round it is then.

[David Schweizer]

I find it difficuly to comprehend some of the negative comments about Hep20 plumbing. There are at least five incarnations of the fittings starting with the original brown "Acorn" fittings through the, otherwise identical, grey fittings and the restyled later grey fittings all of which used the metal grip rings and were interchangeable. About ten years ago it was re designed to use first the white plastic grip rings, and later the green grip rings which were also interchangeable. I am not familiar with the latest "wavin" inserts so cannot comment on them.

 

We have all five types of Hep20 on our boat and despite some of it being there for nearly thirty years, I have never had a joint fail, In fact I find it difficult to see how they can fail except if the pipes get frozen solid, but then conventional copper plumbing is not too happy about freezing either. I can only assume that people who have had problems, have have failed to install it correctly.

Edited May 23, 2011 by David Schweizer

[canaldrifter]

I find it difficuly to comprehend some of the negative comments about Hep20 plumbing. There are at least five incarnations of the fittings starting with the original brown "Acorn" fittings through the, otherwise identical, grey fittings and the restyled later grey fittings all of which used the metal grip rings and were interchangeable. About ten years ago it was re designed to use first the white plastic grip rings, and later the green grip rings which were also interchangeable. I am not familiar with the latest "wavin" inserts so cannot comment on them.

 

We have all five types of Hep20 on our boat and despite some of it being there for nearly thirty years, I have never had a joint fail, In fact I find it difficult to see how they can fail except if the pipes get frozen solid, but then conventional copper plumbing is not too happy about freezing either. I can only assume that people who have had problems, have have failed to install it correctly.

 

I attended a seminar at Hepworths when Hep2O was still fairly new. The instructor was horrified when one plumber declared that he never used the inserts, and the system still worked fine without leaks!

 

If the system is used correctly, in whatever form, then I agree it should not give problems. The only time I had a burst on the boat was indeed due to a pipe freezing, and the resultant joint replacement was a lot easier and quicker than replacing burst copper pipework. Usually the flexibility of Hep2O will cope with freezing conditions.

 

Can't say the same for it's cheaper rivals though.

 

Tone

[Ryeland]

Usually, rule of thumb stated that 15mm pipework would supply three radiators adequately, any more would require 22mm pipework, up to the point where three rads were left on the circuit.

 

I can't think of any situation in a narrowboat where 22mm pipework would be necessary, unless it would be for gravity circulation from a solid fuel backboiler.

 

Tone

The circulating pump in Alde or Webasto type systems is very small, and needs minimum resistance to flow in the pipework to work properly. The advice I have read is to use 22mm until only 1 rad remains to be fed, then drop to 15mm. This works fine with my Webasto.

[David Schweizer]

The circulating pump in Alde or Webasto type systems is very small, and needs minimum resistance to flow in the pipework to work properly. The advice I have read is to use 22mm until only 1 rad remains to be fed, then drop to 15mm. This works fine with my Webasto.

For those of us with "old" boats utilising the Ellis Heatmaster, the instalation insrtuction specify 28mm pipework.

[canaldrifter]

The circulating pump in Alde or Webasto type systems is very small, and needs minimum resistance to flow in the pipework to work properly. The advice I have read is to use 22mm until only 1 rad remains to be fed, then drop to 15mm. This works fine with my Webasto.

 

15mm pipework in my Alde CH system works fine driving three rads on a flow and return system. I have seen many single pipe systems installed in boats. Obviously these will be less efficient and present more resistance to flow.

 

Tone

[sharpness]

Usually, rule of thumb stated that 15mm pipework would supply three radiators adequately, any more would require 22mm pipework, up to the point where three rads were left on the circuit.

 

I can't think of any situation in a narrowboat where 22mm pipework would be necessary, unless it would be for gravity circulation from a solid fuel backboiler.

 

Tone

Mikuni installation instructions specify 22mm flow & return with 15mm to rads (or did when I put mine in 6 years ago!!)

 

Steve

[steelaway]

Just for simplicity I basicaly ran 4 x 22mm coils down the length of the boat

 

2 for CH and two for hot & cold water and into the calorifier - teeing of them to 15mm where needed - Simples

 

Alex

[Nickhlx]

Just for simplicity I basicaly ran 4 x 22mm coils down the length of the boat

 

2 for CH and two for hot & cold water and into the calorifier - teeing of them to 15mm where needed - Simples

 

Alex

 

 

Trouble with 22mm pipe is you have to run around double the water volume through to get the hot from the tank - flow rate for one basic or sink tap on a 3 bar system is more than adequate with 15mm pipe, so using 22mm instead of 15 for the hot pipe run is a waste of water, heat (in summer) and time waiting for it to arrive.

 

Nick

[Justme]

As boats have a limited supply of water I would feed the hot taps via a 10mm pipe. Less water lost due to running till hot & less standing losses as the volume is lower. You would get higher flowing heat losses as the pipe has more surface area to its volume than bigger pipes. But I still think its worth while.

[RLWP]

I find it difficuly to comprehend some of the negative comments about Hep20 plumbing.

 

<snip>

 

Our neighbours got a mutual friend (an ex-plumber) to do some pipe work in their house and had nothing but trouble and leaks. I never did find out how a plumber could make a complete mess of such a simple system, although I believe it was to do with dismantling the fittings first

 

Someday I may take a picture of the nest of Hep2o lianas that run up beside our boiler that I put in twelve years ago. Can't do that with copper

 

Richard

[canaldrifter]

Trouble with 22mm pipe is you have to run around double the water volume through to get the hot from the tank - flow rate for one basic or sink tap on a 3 bar system is more than adequate with 15mm pipe, so using 22mm instead of 15 for the hot pipe run is a waste of water, heat (in summer) and time waiting for it to arrive.

 

Nick

 

It's also more costly, less flexible, and more difficult to box in, as well as unnecessary on narrowboats.

 

Tone

[Nickhlx]

It's also more costly, less flexible, and more difficult to box in, as well as unnecessary on narrowboats.

 

Tone

 

 

Agree - In my house was initially 22mm coming down from the hot tank and it took an age for the hot to come through, so I replaced with 15mm - cheaper obviously, easier as you can push the plastic pipe through and bend it around obstacles, less joints if you use the coiled pipe so much quicker to install, especially compared to copper, if using either compression or solder connectors, and overall cheaper, so to me I will only use copper now if near a heat source or for aesthetics...

 

Nick

[canaldrifter]

Agree - In my house was initially 22mm coming down from the hot tank and it took an age for the hot to come through, so I replaced with 15mm - cheaper obviously, easier as you can push the plastic pipe through and bend it around obstacles, less joints if you use the coiled pipe so much quicker to install, especially compared to copper, if using either compression or solder connectors, and overall cheaper, so to me I will only use copper now if near a heat source or for aesthetics...

 

Nick

 

H'mm.... but we're talking about boat installations, not house installations. Boat's water systems are pumped. House hot water supplies are usually gravity unless from a combi.

 

22mm hot water feeds from cylinders are the norm in domestic situations, because it gives more volume of water. In fact 1 inch pipework used to be fairly common. It will take a lot longer to fill a bath through 15mm pipework than through 22mm by gravity.

 

Similarly, in the old days of solid fuel back boilers, gravity CH systems were often fed by large bore pipework throughout. Nowadays with pumped systems, 22mm is only needed as far as where the circuit supplies three or less rads.

 

Micro systems are a whole different ball-game, but I don't see why they couldn't be used for CH on boats, though they require each separate radiator to have its own flow and return back to a central manifold.

 

Tone

[Bobbybass]

My Jabsco Sensor-Max VSD ( 31755-series 4.5 GPM) SPECIFIES 3/4 inch (22mm) hose in and out with the 15mm only being acceptable on the lesser 3.7 GPM model.

 

Bob

[canaldrifter]

My Jabsco Sensor-Max VSD ( 31755-series 4.5 GPM) SPECIFIES 3/4 inch (22mm) hose in and out with the 15mm only being acceptable on the lesser 3.7 GPM model.

 

Bob

 

If you need such a powerful pump, and that much flow, then that would be correct.

 

Tone

[Bobbybass]

If you need such a powerful pump, and that much flow, then that would be correct.

 

Tone

That's what I have on my boat.

 

With that...and my home made solar water heating...I'm just...cleaner...than everyone else....

 

Bob