Lessons from leaks
A few days ago the joint above this pump on our heating system started to leak. I was alerted to it by the RCD tripping in the fusebox due to the water ingress into the pump's electrical supply. A plumber (turned out to be the same guy who had replaced a faulty main PCB on our Grant heat pump 2 years ago) soon fixed the leak by replacing a seal inside the joint.
It was then that he said this is the auxiliary pump which just speeds up delivery of hot water. It's optional, you don't have to have one. You can turn it off and save electricity if you don't mind waiting longer for the taps or shower to deliver.
If he's right then I think it was installed incorrectly. It is wired into the Honeywell timer which is set to switch space heating off when the water is being heated and vice-versa. The pump can only come on when the timer is set for the heat pump to heat the water. When space heating is on (ie most of the time) then the pump is off. So, it can't be speeding up the supply of hot water when a tap is turned on.
It appears to me me that, as wired, this pump (a £200 componenet) serves no useful purpose. Could I be right?
Mike
Grant Aerona HPID10 10kWh ASHP
I'm guessing the pump is there to boost the flow of the water, in a low pressure DHW system? Try turning it off somehow, or turning it down, see if you can tell the difference!
Alternatively, in larger houses and hotels, it's common to have a hot water return line, so the hot water is circulated back to a tank either on demand (eg when the bathroom light is turned on) or constantly. This means that when you turn on a hot tap, it's much quicker to give hot water. They obviously waste a lot of elec and heat. A better solution in a home is likely to use smaller bore pipes direct to the tap - the flow speed will be a lot higher, so there will be less wasted water before it gets hot, and less wasted heat afterwards.
- 22 Forums
- 2,096 Topics
- 46.1 K Posts
- 72 Online
- 3,383 Members
Join Us!
Trusted Installers
Struggling to find a reliable heat pump installer? A poor installation can lead to inefficiencies and high running costs. We now connect homeowners with top-rated installers who deliver quality work and excellent service.
Verified, trusted & experienced installers
Nationwide coverage expanding
Special offers available
Latest Posts
-
RE: Mitsubishi cycling while on chilled water output
I think that explains it. Unless you can somehow incre...
By JamesPa , 13 hours ago
-
RE: Adding battery storage to SolarEdge PV system
@chandykris No need to apologise at all! I forgot to ad...
By Toodles , 16 hours ago
-
RE: Say hello and introduce yourself
Yes please do Suggesting a loss in the region...
By JamesPa , 17 hours ago
-
RE: Surface mount or bury primaries for heat pump installation?
Can we have some links to those you're considering plea...
By Transparent , 17 hours ago
-
RE: Weather compensated secondary circuits with Biomass
If anyone’s going to know the answer to this it’s @sune...
By Mars , 1 day ago
-
RE: Commencing on an ASHP Installation Process
That outside pipework would concern me. Surely rigid se...
By benson , 2 days ago
-
As I have reported elsewhere we turned on the cooling o...
By downfield , 2 days ago
-
-
@el3b Hi, sorry to hear that, it is advisable to instal...
By ASHP-BOBBA , 3 days ago
-
RE: Difficult positioning of air source heat pump
@rikiarn Out of intrigue, the thread reads as though Ai...
By Sheriff Fatman , 3 days ago
-
RE: Mitsubishi Ecodan Fails to Heat Water despite temperature drop
@m1kegibson If you are able to access the service me...
By HarriUp , 3 days ago
-
RE: When will heat pumps and install prices come down?
... which of course is impossible because the world mov...
By JamesPa , 3 days ago
-
My advice is reject unless they will delete the buffer ...
By JamesPa , 4 days ago
-
RE: Battery storage to run Heat Pump.
I would be surprised if the battery chemistry is going ...
By Transparent , 4 days ago