New Lay-Z-Spa running tips please :)

BPL85

Hi (and yes I know terrible timing to get one haha!).

We have budgeted just to use as a treat at the weekends. It's the Madrid which is a 2-4 seater I believe and we have the app and can set a schedule.

If we are planning to use Friday evening-Sunday evening what schedule is best to use? During the week while not using I'm guessing to run at a lower degree (say 25??) and then get it cranked up Friday morning so ready for the evening? I think it's about 1.5C/hour to heat up based on yesterday.

Also which buttons should be left on constantly? Such as pump and temp one? Do I need to select the schedule button aswell on the terminal to overide other settings?

Thanks so much
Ben

Aylesbury_Duck

Ouch.  Once the new electricity prices come in in April, I suspect you're looking at several hundred pounds of electricity costs every year just to keep the thing ticking over, before the added cost of cranking it up for actual use each weekend.  Heating a large volume of water to 25C and maintaining that temperature all week, every week is going to cost a fortune.

As with home heating, kettles, etc. the most energy efficient method is to turn the power off completely until you need to use it, then work out how early you need to turn the power on to get from whatever the ambient temperature is up to the desired temperature (c. 40C I guess?).  However, I expect there are things you have to do to maintain water cleanliness, maintain the warranty, etc which may mean you have to have it powered at all times?

Just looking at the typical running costs of these, if I had one it would double my household's current annual electricity consumption.  Eek.

BPL85

Yeah we have budgeted around £1,000 a year as it's like a little escape each weekend rather than going away. We will also be emptying it a couple of times a year and keeping off for a little while.

I'm not sure completely off would be best as takes so long to heat up if using every weekend. And like you say upkeep of chemicals etc wouldn't be so good.

If it's coming out much more than £1k we will just run for a year and see it as a holiday experience and sell for peanuts along with everyone else haha, it's lovely though

Aylesbury_Duck

What are the warranty conditions and do they specify minimum temperatures, frequency of pump running, etc?  They're your first port of call so you don't invalidate it.  As you say, some of the chemicals might not be effective below certain temperatures.

Don't fall into the trap of thinking it's energy efficient to keep something warm permanently in readiness for use.  It's an old central heating myth but the principle applies.  If it takes 48 hours to get it from ambient to useable temperature, it's still cheaper to do that than to run it warm all week and then for 12 hours intensely to get it up to temperature.  You don't keep your kettle ticking over at 60C all day in readiness for a cup of tea at 100C two or three times a day.

matelodave

You can do a few sums based on it's capacity, the rating of the heater and pump and it's heat loss to try and work it out but as said above heating a lot of water and trying to maintain the temperature isn't going to be cheap, especially during the colder months.

You need to keep the cover on to retain heat and keep it clean when its not in use - especially when it's heating. It may be a faff to keep taking it on and off abut the more heat it retains the less it's costs to maintain it's temperature or reheat it. It would be cheaper to let it get cold during the week and then just reheat when you are going to be using it.

Cooler water loses less heat to the surrounding air than hot water so maintaining 25 degrees all week when its not in use will cost a lot more than just heating it when you want to use it, especially when the novelty wears off and you probably wont use it every weekend.

BPL85

Thanks both, that's what I'm wondering. Maybe let it just run cold then - Sunday 11pm-Thursday evening so off for over half the week. If it goes down to 10/15C it would take the best part of a day to warm up so ready for Friday evening. I presume still need to keep on though for filter etc...hopefully someone with a tub can help I don't think it will wear off but I appreciate does for some!

BPL85

Not sure on warranty but will definitely have T&C's about regular upkeep I'm sure haha!

pochase

We were running our hot tub 24 hours until a few months ago at 35 to 38 degree depending on outside temperature/time of the year. During summer the energy use was 7KWh per days, in winter more like double this.
We were using the hot tub almost daily so we found that for us switching it off and reheat it did not make sense.

This "low" consumption was possible due to a hard top thermal cover plus a thermal blanket. Cost of this was around the the 1000£ per year you are prepared to pay, but at a reasonable rate of 14p per KWh. 

I can confirm the 1.5 degree per hour heating up the hot tub. So if you heat it up from 25 degree you are looking at 8 hours use of a 2KW heater. Keeping the 25 degree going in winter will require additional heating, no idea how much that will be.

Also the pump itself still needs be running a minimum of 8 hours a day, even if the heater is not used, to keep the water quality. Keep in mind that if there are minus temperatures the water in the pump might freeze and damage the pump if it is not running.

Get yourself an energy monitor and measure the use over a few weeks to make sure what your worst case scenario in winter will be.

BPL85

Thanks pochase! So tricky to decide what's best. Would you guess maybe best to set at say a safe 10C - wouldn't normally get that low unless VERY cold anyway. Then say 12-18 hours prep heat on Thursday/Friday?

QrizB

pochase said:

This "low" consumption was possible due to a hard top thermal cover plus a thermal blanket. Cost of this was around the the 1000£ per year you are prepared to pay, but at a reasonable rate of 14p per KWh.

That's still around 7000kWh/yr even with thermal covers etc. which will be costing £2000/yr from April!

pochase

QrizB said:

pochase said:

This "low" consumption was possible due to a hard top thermal cover plus a thermal blanket. Cost of this was around the the 1000£ per year you are prepared to pay, but at a reasonable rate of 14p per KWh.

That's still around 7000kWh/yr even with thermal covers etc. which will be costing £2000/yr from April!

This is why we have switched it off for now and will only use it during summer when it is really hot in future, even so it was more like 3500KWh than 7000KWh.