Blended hot outside tap from gravity

[fowlerboi]

Customer wants an outside tap for dog washing so needs to be blended. The hot water is gravity and its a bungalow so little head at the point of installation. I can't get a cold from the storage cistern to the utility so it has to be mains cold.

Can pressure reducing valves be taken down to 0.3bar and still function correctly or are the flow rates going to be pathetic?

Would Gravity hot water into a blending valve meeting a cold main reducded to 0.3 bar work well enough to wash dogs?

 

[Timmy D]

Usually they go down to about 0.5 bar.

 

[ShaunCorbs]

I wouldn’t you could pee faster

Think your not going to win

 

[fowlerboi]

Right so what about a 30L water heater? At 60c in the heater blended down to 30 (keeping it low to make the most of the hot water) you would get a 50/50 blend? Meaning 60L of hot water at something like 10lpm if I restricted it which would be easily enough to wash a dog you would get 6 minutes of dog washing. The customer has 5 dogs so that would allow for just over a minute per dog.

I'm no dog owner but would that be sufficient?

Looking for solutions before I tell her it can't be done

 

[ShaunCorbs]

Yep that’s the way I would go or and instant one but you will need a 40-50 amp electric for that

 

[Deleted member 120897]

What about a single impeller pump for dhw?

 

[MikeJhn]

In line shower booster pump, designed for the purpose of increasing hot water flow with indirect systems: Shower Booster Pump - https://plumbhq.uk/products/shower-booster-pump?

 

[fowlerboi]

Looking at something like this?

I've very little experience with booster pumps but the last one I did was recommended stuart turner and avoid salamander. Any other recommendations?

A water heater would be my prefered choice but I am a little worried about running out of hot water

 

[ShaunCorbs]

Pump would have to be at the cylinder via an s or e flange

 

[MikeJhn]

In line shower booster pump, designed for the purpose of increasing hot water flow with indirect systems: Shower Booster Pump - https://plumbhq.uk/products/shower-booster-pump?

Fitted one on the kitchen sink supply not near the cylinder and it works fine.