DIY Laser levelling using webcam and laser level

**Kitwn** · 19-01-2020

I recon you're missing an opportunity here Dean. Get Joe in as optical consultant and then get John to pop over from Melbourne and build you an add-on Z-axis assembly that can grind kitchen bench offcuts into surface plates for cash at the weekend when nobody's looking.

Kit

PS Joe is that really a swimming pool in Pommieland?! I hope it's got solar heating. Even in Perth we only used ours for a few months around Christmas.

**devmonkey** · 19-01-2020

Originally Posted by Kitwn

PS Joe is that really a swimming pool in Pommieland?! I hope it's got solar heating. Even in Perth we only used ours for a few months around Christmas.

Yeh I was sceptical too but the kids and missus were rather insistent ! I used ICF for the walls helps a lot with heat loss, and it uses a 39KW air sourced heat pump which has a COB of about 10-15, you put in 3kw of electricity get out 30kw of heat, that together with global warming lets us keep it at 28 degrees from May-Sept, it has ice on it today though. Biggest electrical expense is the water pump, going to convert this to DC and run it directly off a couple of solar panels next season. Hardest part of making it was wiring together 3km (I kid you not) of rebar before pumping the concrete, I had bloody hands doing that for a fortnight.

Getting a bit off topic but anyone interested in getting a swimming pool, build it your self as I did. It cost less than a decent CNC router, £1k for rebar, £5k concrete, £1k ICF and then £3k for some locally licensed rip off merchant to fit the liner. Local pool company came round to have a look when it was finished and told me they would have charged me £80k for building it.

**JAZZCNC** · 19-01-2020

Originally Posted by devmonkey

Local pool company came round to have a look when it was finished and told me they would have charged me £80k for building it.

80K for a hole in the ground, they must be on drugs. To be honest, I wouldn't pay 11K either, living in Yorkshire we are surrounded by dozens of old Pit sites and brickworks which all had great big clear blue ponds(well not all clear blue.!), which as kids we lived in. most are still there and know nature reserves or fishing ponds so who needs a heated swimming pool... Lol

**devmonkey** · 19-01-2020

Originally Posted by JAZZCNC

80K for a hole in the ground, they must be on drugs. To be honest, I wouldn't pay 11K either, living in Yorkshire we are surrounded by dozens of old Pit sites and brickworks which all had great big clear blue ponds(well not all clear blue.!), which as kids we lived in. most are still there and know nature reserves or fishing ponds so who needs a heated swimming pool... Lol

Everything with swimming pool in its name has a 10x price multiplier. The guy to fitted the liner has a 'swimming pool liner vacuum pump' to suck the plastic liner onto the pool shell, this machine cost him £2k. It was a £60 machine mart dust extractor fan like we use in our workshops with a nice stainless steel pool company badge plate riveted over the 'Clarke' label, unbelievable.

**Clive S** · 19-01-2020

a 39KW air sourced heat pump which has a COB of about 10-15, you put in 3kw of electricity get out 30kw of heat

I would be interested in the make and model of the air sourced heat pump as I thought that they were only about 3-4 times the input.

**devmonkey** · 19-01-2020

Originally Posted by Clive S

I would be interested in the make and model of the air sourced heat pump as I thought that they were only about 3-4 times the input.

Here you go,
https://www.heatpumps4pools.com/prod...ol-heat-pumps/

"Excellent COPs – from 5.8 to 15.8 due to Inverter technology"

Depends how hot the air is relative to the water temp, I don't think you can expect the same when you use them to heat your house in the winter as some people are starting to do. Mine is the 27kw single phase one, not 39kw as I originally posted, brain glitch. Once up to temp it just runs at tick over for most of the summer and stops all together on hot days.

**Kitwn** · 20-01-2020

Originally Posted by devmonkey

Here you go,
https://www.heatpumps4pools.com/prod...ol-heat-pumps/

"Excellent COPs – from 5.8 to 15.8 due to Inverter technology"

Depends how hot the air is relative to the water temp, I don't think you can expect the same when you use them to heat your house in the winter as some people are starting to do. Mine is the 27kw single phase one, not 39kw as I originally posted, brain glitch. Once up to temp it just runs at tick over for most of the summer and stops all together on hot days.

Over here it's called 'reverse cycle air conditioning' you can either heat or cool your house depending on the season. Heating is no good when it's so cold the outside unit freezes up but in more temperate climates like most of Australia it works well. If you need air-con for the summer anyway it's a cost effective heating system to install and to run.
OK, back on track

**Clive S** · 20-01-2020

Originally Posted by devmonkey

Here you go,
https://www.heatpumps4pools.com/prod...ol-heat-pumps/

"Excellent COPs – from 5.8 to 15.8 due to Inverter technology"

Thanks for the feedback. But it also states this

"Bear in mind though that there is no international standard for stating COPs and therefore each manufacturer will state the maximum COP obtainable for their units under optimum temperature and humidity conditions. In reality you may not therefore always acheive the COP rating stated."

I have been involved in installing a few heat pumps air source and ground source and I believe that they were in the region of about 3-4 to 1. My next door neighbour has had his gas taken out and put in an air source pump. I am very interested to see the results over time.

**devmonkey** · 20-01-2020

Originally Posted by Clive S

Thanks for the feedback. But it also states this

"Bear in mind though that there is no international standard for stating COPs and therefore each manufacturer will state the maximum COP obtainable for their units under optimum temperature and humidity conditions. In reality you may not therefore always acheive the COP rating stated."

I have been involved in installing a few heat pumps air source and ground source and I believe that they were in the region of about 3-4 to 1. My next door neighbour has had his gas taken out and put in an air source pump. I am very interested to see the results over time.

Hi Clive,

All I can tell you is throughout a season the total kwh used by the heat pump is is about the same or less than the 1hp water pump that is switched on for exactly the same time, I have clamp on current monitors on both going to the main energy logger in the house. The heat pump pulls about 2.9kw max and will bring 60m^3 of water from 18 to 28 degrees in a couple of days. Costs about £1k in electricity to run both per season. I have no experience of them in houses although a friend who has also just rebuilt his house is now relying solely on an air sourced heat pump for house heating with hot water boosted with immersion and tells me he is saving a fortune, but he wasn't on mains gas rather oil delivered by tanker which is expensive.

What maybe of interest is I had a 10kw pump heating a much smaller 10m^3 above ground pool, this was the older generation pump without the inverter and therefore constant compressor speed / current draw. The electricity cost of running this unit was the same per season as the new pool system, therefore it must have been much less efficient.

**mekanik** · 20-01-2020

Clive
I looked into heat pumps several year ago, obviously ground source is the most efficient but due to my building plot this is not an option, max for air source is in the region of COP 5
https://www.viessmann.co.uk/products...s/vitocal-300a
Regards
Mike