Hot water recirculation pump good idea? Grundfos?

Page 29.....

https://www.johnguest.com/speedfit/...Plg-Product-Guide-UNPRICED-Z2105-394-0414.pdf

A continuously operated re-circulating system is a water-replenished circulating system which is maintained at a constant high temperature to provide a constant source of hot water. Continuously operated recirculating systems are used to distribute constant hot water to draw off points that may be distant from the source or hot water storage vessel. Continuously operated re-circulating systems are very different from conventional hot water supply and central heating systems found in domestic properties, for which our products have been tested to, under either BS7291:2010 Class S or WRAS approval standards, and for this reason Speedfit products must not be used on any continuously operated re-circulating systems as they are not approved under the current version of these standards
Interesting. So basically what John Guest is saying they haven’t tested their products on recirculating hotwater systems so don’t use it and moan at us if anything goes wrong
 
Sponsored Links
I guess fresh aerated hot water can take it’s tole on any form of pipework. Especially ones with rubber seals.
 
Sponsored Links
Well thanks boys! That's about as comprehensive as it gets. Copper it is then. (More bloody money lol)

I've had a good read over the grundfos comfort pumps. I can't quite decide if the self learning ones are worth all the extra money.
Also as a side note, there are essentially 4 pumps.
2 have a one port to port size, 2 have a bigger port to port size. (80mm and 110mm)
What exactly does that mean to me? I doesn't suggest there Is a difference in flow rate from their specs, so is it just a mounting size for already installed systems? If that's the case, being as I will be installing all of this new is there a preferred size I should choose? The 80mm is considerably cheaper.

Alex
 
I can't quite decide if the self learning ones are worth all the extra money.

Does it "learn" on a daily basis ( all days are the same ) or a 7 day week basis ( Weekends different to weekdays ).

Personally I would opt for the temperature control option.
 
We use the Auto Adapt Grunny Comforts more or less exclusively unless direct replacement on existing systems:

20171024_153825.jpg

20171024_153758.jpg


They work better than traditional time and temperature setups as they're basing the future on and off times based on previous draw off and measuring the water passing from the cylinder back to the pump. Note the little red temp probe under the pump in the second picture - that gets strapped to the hot draw off about a metre from the cylinder.

Decent secondary pump + Decent timer + pipe stat + installation time + installation materials will work out roughly cost neutral to a Grundfos smart pump and a 3 pin plug.


Beware advise from those that do not do this for a living

Buteline which is a crimping system are happy for their product to be used in condition that the Pump is only in use for active periods.

i'd be surprised if Buteline are happy for their crap to carry water full stop, let alone put their fittings through the stress of secondary returns.
 
as they're basing the future on and off times based on previous draw off and measuring the water passing from the cylinder back to the pump.
Does it memorise the draw off pattern over a week thus allowing for Saturday and Sunday to be different from weekdays ?
Can it do that accurately from just a single temperature sensor that is not positioned at the point of delivery ?
 
Does it memorise the draw off pattern over a week thus allowing for Saturday and Sunday to be different from weekdays ?
Can it do that accurately from just a single temperature sensor that is not positioned at the point of delivery ?

Couldn't be sure of the exact number of days. And it is not just a single sensor at the point of delivery. It is a sensor at the point of draw off and one in the pump. So it know when the system is both up to temperature and when it is being used using ΔT/time.
 
Does it memorise the draw off pattern over a week thus allowing for Saturday and Sunday to be different from weekdays ?
Can it do that accurately from just a single temperature sensor that is not positioned at the point of delivery ?

Yes Bernard and it will also have a cup of tea and jam on toast ready for you at 7:30 on a Saturday morning, shortly before you use the washbasin!
 
from just a single temperature sensor that is not positioned at the point of delivery
And it is not just a single sensor at the point of delivery.

The system that worked for a B&B with 4 en-suite rooms was a thermostat on the point furthest from the cylinder. When that went cool the pump ran long enough to bring hot water to that point. Simple and it worked for years.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top