Return loop

[ziggy1979]

Hi everyone!

Been getting some help in the other forums and thought I'd turn my sights on plumbing next!

We are building 8 showers in changing rooms. I've been told that we should consider having a return loop with pump for almost instant hot water. But, truth be told, we aren't worried about a 20-30 second run of cold water which we've found to be normal at many sports halls and gyms.

After reading up on them, other than instant hot water, the only other benefit I found was a reduction is wasted (cold) water. However, from my understanding, the water at the property is not on a meter (old commercial premises). Also, the water saving comes at the cost of using gas to reheat the water being pumped (using electricity) back to the water heater.

Also, for a return loop we need to spend more money on pipe, pump, valves and labour.

So, from my limited understanding, I don't think we need it. That said, I'd be really grateful for your views and advice.

Thanks for all your help!

Zigs

PS - I've been looking at Lochinvar hot water heaters. They seem pretty good but pricey. Are they the best, overpriced, other brands that are better priced, etc? Thanks!

 

[Charnwood]

As there is no financial gain to be had, don't do it. It will just be extra costs - pump etc, bigger gas and electricity bills, although the bills should not be a lot bigger if used properly by fitting timers or just switching on manually when required.

I'm not sure return loops are suitable for combi/instantaneous heaters. Might be wrong.

 

[ziggy1979]

Hi Charnwood

Thanks for your reply.

Are there any potential negatives I've overlooked in not having a return loop (other than the cold water issue).

Thanks again!

Zigs

 

[slapper]

12 showers, you need to do a lot more homework on other factors before worrying about a secondary return Rodney.

 

[ziggy1979]

Hi Rodney

Thanks for your post.

We are having 8 showers but it would be helpful to know what you mean by "homework".

1. We have checked the water and gas supplies and both have been confirmed as sufficient.
2. We have calculated peak usage/demand on both 9 l/min and 6 l/min (we are looking at using shower heads with reduced flow rates).
3. We've looked at water heaters with varying storage (300-400+l) and reheat times down to 18-19 minutes.
4. We have decided to use push valves rather than taps to ensure minimal water wastage, especially showers left running after people have left them. Water will also be supplied at a fixed temperature.
5. We have considered max usage of 50 (total) showers at peak time in one hour (ie 6 showers per cubicle per hour with water running non stop for five minutes each shower).
6. Calculations for water heaters have been based using the above data.

Please let me know if there is anything else we should look at and also, anything we may have overlooked in concluding that we don't need to invest in a return loop.

Thanks again..

Zigs