Search the forum,

Discuss Advice required: Heating a large volume of water with LPG Gas boiler in the Plumbing Jobs | The Job-board area at PlumbersForums.net

Status
Not open for further replies.
D

DawnR

First time posting on here and I am after some help and advice on a project I have ongoing at home - a bit cheeky I know but as they say around here ‘Shy bairnes get nowt’!


My children (10 and 8 at the time) were lucky enough to be given an above ground 15ft round swimming pool from some retired friends of my parents when they down-sized and moved house... Oooh lovely I hear you all say, imagining relaxed BBQ’s and drinks whilst the children splash around the pool in the during the long, hot summer evenings... Unfortunately, we live in the windiest, chilliest part of rural Northumberland where the daffodils don’t even come into flower until June! After a few chilly dips and near cases of hypothermia in my little ones I decided that there must be a way to make this pool useable. I have now exhausted all other financially viable options (the sorry tale is written out below for you to read if you are in need of a little light humour!) but we have still got a cold, cold pool.


As a last ditch stand I am thinking of using a Gas boiler, converted to LPG as we don’t have piped gas, housed in a small shed on a timer, heating the water in a indirect hot water cylinder (with a coil of pipe inside) which in turn heats the surrounding water pumped in from and out to the pool. Does this sound possible lovely plumbing people? And if so have you got any suggestions as to what type of boiler or tank etc to get.


... Or if you can suggest anything else (apart from giving it all up and just sticking to my day job) I would be very grateful to hear it.


Thanks in advance folks!


The story of heating the pool so far... Grab yourself a nice cuppa and sit comfortably—you may be here for a while!

First year:

1) Wetsuits - Hmmm better, but still blue lips after less than 10 mins in the water.

2) A solar cover - These appear to work well in the sunny state of Florida... Northumberland not so well!


Second year:

3) A homemade Geodome to keep the wind-chill factor down - makes a huge difference but still freezing.

4) A home made solar panel put in-line after the pool filter to warm the water, great on the 2 days a year that we have enough sunshine - and my son got to learn how to harness solar energy and take photo’s of this to school to explain how he made it, other than this not much good for heating the water!


Now at this point the lovely idea of a pool for the children to splash about in is beginning to become more of a challenge and the first signs of my stubborn side begin to show ‘it is NOT going to beat me again next year’ I vowed!


Third year:

5) Reckless optimism rules once again! Rockwool insulation wrapped around the perimeter of the pool to minimise the heat lost once my new master plan is put into place.

6) ... The master plan! A very old and rusty wood burner with a back boiler was given to me by my parents. A submersible pump connected to the burner drew cold water out of the pool and around the back boiler. When the stove was roaring it then returned lovely warm water to the pool - simples! No, not bloody simples at all. The water from the back boiler (although lovely and warm as I had planned) was now rusty and our crystal pool turned a lovely shade of orange!

7) Research on the internet revealed instructions to make a fluff filter which consisted of a large water bottle with many holes drilled into it and stuffed with fluff from a duvet or pillow, the filter was fitted to the outlet of the burner and collected all the rust particles. This worked a treat but needed re-making every few days due to the amount of rust coming out and if the water was too hot then it melted the fluff altogether!


But yay this works a treat: Solar panel and regular pool filter, submersible pump, back boiler and fluff filter, 20 tonnes of chlorine and pH plus to stop nasties growing in the water and after a few days we have a lovely pool at 28°. Happy, happy children - and a rather smug me I have to say. Sorted!


Forth year:

8) Pool drained for winter, re-filled in daffodil flowering season :) - leak somewhere... Grrr, drained, found 6x mouse nibble holes, repaired and refilled with our arctic tap water (thank goodness we are not on a meter!). Pump submersed, fire lit and away we go! Now I really should have stopped here and been happy with my lot. But due to water and electricity safety issues the little ones could only swim in the pool when the pump is out/unplugged... and if it is not pumping cold water into the back boiler then the fire must be also be out or it will boil and pop the home-made safety valve (a cork gently pushed into one of the outlets) and a geyser of boiling water will spurt out - all very unpleasant unless you want lightly boiled bluetit with your BBQ!

So how about a sealed system? Hot water pumped, from the back boiler of the fire by an external pump, around radiators which have been submersed in the pool and which will heat up, just as in the house and conduct their heat into the pool water - no need for filters because the rusty water is not going directly into the pool. No! No, No, No I hear all you experienced plumbers cry - what do you expect to happen to the old steel radiators when you put them into water? Well I thought (!) the paint on the radiators would be sufficient to protect them from rusting - ha, no chance!


9) Special mounts were made to ensure the radiators were raised up to allow water flow over the fins and to protect the pool liner from getting any more holes in it. Pipes and connectors were bought and fitted, the radiators were filled and bled. The system was topped up to full, a small header tank was made and fitted to allow for any expansion as the water heated up. And the grand switch on happened.


10) The force of the second hand central heating pump being so close to the rusty old back boiler was enough to cause it to leak and put out the fire. At this point it is becoming less of a personal challenge and more of a nemesis... My eyes are now turning red, steam begins to pour out of my ears and the children have taken cover under the dining table!


11) Deep breath, this will NOT be my downfall - After yet more internet research I found and bought some high heat, flameproof putty to fix the leaky spot. Leak fitted and away we go again! Slowly, slowly the icebergs floating in the pool melted and the pool temperature began to rise - happy, smug me again! However, as you clever plumber people predicted over 250 words ago, this was a short lasting smugness as before my eyes the water turned a rusty yellow yet again! Pool drained, radiators out.


Fifth (!!!!) year and the family stubbornness gene is well and truly showing now... I am a professional, have a high pressure job, have peoples lives in my hands, am educated and also practical, I have the World Wide Web and all that information at my disposal, I have shown cunning, patience and adaptability so why oh why is heating up a volume of water proving to be so difficult? It is now no longer ‘for the children’ but is a matter of not being beaten, a matter of not giving in, a matter of ‘I wish I had just bought a bloody pool heater five years ago’!!! A cold hard look at the lessons learnt revealed that the fire heating the water worked well, the central heating pump was safer but still needed to be turned off when children were swimming, the radiators were a ridiculous idea and the back boiler (the one thing that did work) is now more like a sieve!


12) So copper piping was bought and connected to make a home made back-boiler which was simply a huge snake of copper pipe which also went up and down the chimney twice, in the woodburning stove. It was suspended well above the flames so as not to melt the pipes and cold water would have to flow through continuously when the fire was on. The heat of the fire proved too high for the solder and leaking water in the fire was again the problem.


Sixth year - my energy is now at an all time low: the Geodome needs some plastic panels repairing/replacing, the 20cm of water inside looks like it should feature in the movie ‘The swamp thing’, the bank is no fuller of £££’s so a pool heater remains out of the question and the children still have not had a good few days swimming after of all my efforts... Final (and I do mean final) year at this now. I am thinking of a Gas boiler, converted to LPG as we don’t have piped gas, housed in a small shed on a timer, heating water in a indirect hot water cylinder (with a coil of pipe inside) which in turn heats the water in the tank which is pumped from and back to the pool.


11665501_10155685202995697_7498086382860005561_n.jpg
14237726_10210212997866427_3222837831367648347_n.jpg
 
Well, it's looks like I'm the only one left to assist a 'damsel in distress'.

Can you work out the volume of water in your pool.

Equasion: Pool radius ( 1/2 diameter ) squared x 3,142 x depth.

eg: 4m diameter.

2 x 2 x 3.142 x 0.8m depth = 10.05 m3 of water
= 10,050 litres of water.

Decide on the heat up time of the pool - generally 12 or 24 hours - and the desired temperature of the pool ( 28 C )
The pool doesn't look that big - 6 hour heat up time may be in the equasions.

Get a boiler company or pool company to size a heat exchanger to suit your requirements and run the pool heating off that.

Or reply to the volume of the pool and heat up time and I could get something calculated for you.

You could buy the cheapest of boilers to supply the heating to the heat exchanger and have a pump installed from the pool to the heat exchanger.

The pool doesn't look that big, so you may be surprised how small the heat exchanger will be.

Happy kids - happy mum.
 
  • Winner
Reactions: Dan
Status
Not open for further replies.

Reply to Advice required: Heating a large volume of water with LPG Gas boiler in the Plumbing Jobs | The Job-board area at PlumbersForums.net

Creating content since 2001. Untold Media.

OFFICIAL SPONSORS

OFFICIAL SPONSORS

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock