HELP! Wasting Hot Water With Long Pipe Runs

TreborJ

Hi All,

I'm trying to help out my folks, they built a dormer about seven years ago but with the way it was designed the main bathroom & hot water cylinder is one side of the house and kitchen on the opposite side of the house. Its not a large home but the way the pipes are routed this nearly doubles the pipe run meaning the it takes a very long time to produce hot water at the kitchen sink.

Now I have been looking at a couple of solutions but need some advice or other suggestions would be greatly appreciated.

My first thought was to add in a domestic hot water circuit adding a pump up at the cylinder and adding an additional pipe from the cylinder to as close the to hot water pipe in the kitchen as possible. I can add the pipe without any issue but the cylinder doesn't have a secondary return, but I was told I could add it to the tanks cold feed.

Another solution is very similar to the above but you connect a special valve between the cold and hot tap of the furthers away sink and add a pump to the hot feed, but I have only seen the solution in the U.S., can't find anything similar in Europe, and maybe thats for a good reason? here's an example.
http://www.watts.com/pages/whatsnew/IHWRS.asp

My last option is simply use an under the sink electric heater with a small hot water store but this is my least favourite solution as it will only work for the sink where its connected, I'd prefer a solution that would work not only in the kitchen also the downstairs bathroom.

Forgot the mention that the heating system is oil fire central heating.

Any suggestions on pumps or hardware I should use, or on any other solution would help greatly.

T....

sullzz

You can connect the secondary return to the cold feed , once the non return valve is fitted in the correct position , what i have done before was drill the side of the cylinder and fit a 3:50 into it . Make sure the pump you get is a brass pump and fit a timer to it , or you can get a secondary return pump with an integrated timer , i wouldn't fit an undersink water heater in a domestic situation unless i had no other choice

TreborJ

Thanks for the advice sullzz,

that would be my preferred option anyway.

Regards, T

freddyuk

If you install a hot circuit with a return into the cold feed you must surely be cooling down the hot water in the cylinder and the stratification will be destroyed? The circuit needs to be running all the time to have hot water on tap?
If all you need is a sink of hot water at anyone time it may be worth considering the cost of alternatives. If you have 1/2 inch supply pipe you could install a 3/4 or 1 inch pipe with a timered cable heating which is well insulated like a mini cylinder in the pipe run. Quite a lot of water in a 1 inch pipe. The heat cable can be on timer and thermostat so there is always enough in the line for a sink full. It will of course heat the cold leg as well.
If the 1/2 inch pipe run is long enough just add cable along the length and then you are just heating what you need.

TreborJ

Maybe I'm way off the mark on this question, but the central heating pipes come from an outside shed and pass through the utility room next to the kitchen, Is there any type of heat exchanger that could be connected in-line with the CH hot flow to heat the hot water feed from the tank, or a small buffer tank that would be simular? Or am I talking nonsense??

PeteHeat

How about fitting a small insulated cylinder (30 gallon) in the utility with a themostat and two port valve so it doesn't use heat when not required and plumb that into the kitchen and downstairs bathroom.

Probably easier, cheaper and shouldn't interfere with the rest of the house.

.

TreborJ

PeteHeat wrote: »

How about fitting a small insulated cylinder (30 gallon) in the utility with a themostat and two port valve so it doesn't use heat when not required and plumb that into the kitchen and downstairs bathroom.

Probably easier, cheaper and shouldn't interfere with the rest of the house.

.

Cheers PeteHeat, this could be a good option maybe.
Just seen a 75 litre cylinder supplied by Gledhill. Do you know if I would need to take any safety precautions as like adding a pressure release valve?

roy rodgers

I find this is a common problem with bigger houses and there is no quick way to fix it now.
What I have done for a few people with the same problem was to put a small under sink water heater (10 liter) near as possible to the sink and it has worked a treat for them, they are all very pleased with the results and now the hot and cold water are at the same pressure.
I dont like using secondary returns in houses where hot water demand is only for a hour or two a day as the heat loss is to much and it ends up costing more in the long run.

Just a quick question, How much hot water is needed for the downstairs bathroom?? Is it just for a basin or is there a shower /bath in the room??

TreborJ

roy rodgers wrote: »

I find this is a common problem with bigger houses and there is no quick way to fix it now.
What I have done for a few people with the same problem was to put a small under sink water heater (10 liter) near as possible to the sink and it has worked a treat for them, they are all very pleased with the results and now the hot and cold water are at the same pressure.
I dont like using secondary returns in houses where hot water demand is only for a hour or two a day as the heat loss is to much and it ends up costing more in the long run.

Just a quick question, How much hot water is needed for the downstairs bathroom?? Is it just for a basin or is there a shower /bath in the room??

Thanks roy, but my issue with the under the sink solutions is that there is 3 sinks downstairs, kitchen , utility, and main bedroom on-suite. Upstairs there is only one bathroom and to be honest thats only used when family visit, or maybe over the weekend. the sinks downstairs are used much more often. My father was toying with the idea of changing to LPG gas and using a combi boiler, but there's nothing wrong with the oil fired system besides this issue so it seems excessive to change to whole heating system for this issue.

roy rodgers

Ya could put in a instantaneous water heater in run off a bottle of gas but you will need about a bar of pressure running through it.
But I think peteheat option would be better and probably the cheaper option then.

TreborJ

Thanks Roy, All these suggestions will help me to the solution we need.

paddy147

There was a company at the Ideal Home Show (RDS last weekend) selling these "instant" hot water taps.

A fair few people were buying them.

The sales chap was good at his job too with his sales pitch to all the oaps.

TreborJ

paddy147 wrote: »

There was a company at the Ideal Home Show (RDS last weekend) selling these "instant" hot water taps.

A fair few people were buying them.

The sales chap was good at his job too with his sales pitch to all the oaps.

They may work for a kitchen, but any bathroom or on-suite room will mean adding additional wiring. There's never an easy solution.......

PeteHeat

TreborJ wrote: »

Cheers PeteHeat, this could be a good option maybe.
Just seen a 75 litre cylinder supplied by Gledhill. Do you know if I would need to take any safety precautions as like adding a pressure release valve?

Hi,

The safest way is an open expansion up over the storage tanks in the attic, shouldn't be much of a problem as you will most likely have to run the cold supply down anyway.

If you are looking at a pressurised system my advice is call an experienced plumber because fitted wrong you can have a potential bomb waiting to explode.

.

deandean

Suggest you just insulate the HW pipe with thick lagging (20mm?) and put up with it.

And install an instant hot water source at the sink: either the plumbed-in & obscenely expensive unit or the plug-in €39 Lidlaldi unit with a 1.8L resevoir.

TreborJ

deandean wrote: »

Suggest you just insulate the HW pipe with thick lagging (20mm?) and put up with it.

And install an instant hot water source at the sink: either the plumbed-in & obscenely expensive unit or the plug-in €39 Lidlaldi unit with a 1.8L resevoir.

I think your right, I'm over thinking the problem so I reckon ill just install the under the sink water heater and be done with it.

Cheers all for the suggestions.

T.....