Is it possible to connect domestic hot water and underfloor hydronic heating in one air driven heat pump system? I've talked to one hydronic provider who said their system is sealed, treated to stop bacterial growth and pressurised, therefore the hot water can't be shared with the DHW. Also, i believe DHW runs at 50 degrees and hydronic heating only needs 37-45 degrees. I would love to have DHW, underfloor hydronic heating and swimming pool heating all driven by an air heat pump running either off peak or tied to a 5kW solar system.
Domestic hot water and hydronic heating in one system
(5 posts) (4 voices)-
I'm sure it is possible. I'm not sure it is sensible. In the last three weeks I have been commissioning our air source heat pump hydronic floor system. The floor absorbs so much heat that it returns quite cool water to the tank. Even with a 7kW heat pump, the floor seems able to outstrip the heat supply and cool the tank overall. If we had only this as a DHW system we would be having cold showers too often. Instead we completely separated our systems so that the solar DHW is always reserved for DHW and the floor's heat pump just supplies the floor.
In the next couple of weeks we will be integrating a solar heating circuit into the floor system which I hope will significantly cut our use of the heat pump. It should be ready just in time for summer!
Posted Tuesday 6 Aug 2013 @ 3:46:34 am from IP # -
wlb
MemberYou use a heat exchanger for the domestic hot water.
30 odd years ago I designed (with the help of Tubulous)and built a wood-fired hydronic system for a ski lodge. The domestic hot water was supplied by a simple copper coil in the boiler's main storage tank. It was space heating via radiators and convectors however, not slab heating.Posted Tuesday 6 Aug 2013 @ 3:48:01 am from IP # -
Trisha Drioli
MemberI'm looking at installing a heat exchanger (Bosch 5000W) for domestic hot water and an underfloor pipe network (with in room radiators) for heating (as per the post above).
We also have a combustion wood heater. Is there any problem with attaching a water jacket (is that what they're called? and assuming I can find one) to the combusiton heater and adding it to the new hot water/hydrolic heating system?
Posted Wednesday 7 Aug 2013 @ 7:39:21 am from IP # -
wlb
MemberTrisha Drioli said:
I'm looking at installing a heat exchanger (Bosch 5000W) for domestic hot water and an underfloor pipe network (with in room radiators) for heating (as per the post above).We also have a combustion wood heater. Is there any problem with attaching a water jacket (is that what they're called? and assuming I can find one) to the combusiton heater and adding it to the new hot water/hydronic heating system?
That's how the ski lodge system began. We looked at fabricating a water jacket for the flue of the large potbelly-style heater in the living area to provide domestic hot water heating and a hydronic radiator in the drying room. But we soon realized it was better to replace the heater with a hydronic boiler and review the heating requirements for the whole 2-storey building.
You could fit a water jacket, but it won't be that effective. If too much heat is going up the flue, you need to look at the heater to make use of that heat. If the flue gases are cooled too much then the fire may not draw properly, and when burning eucalypt you will get a combustible resin deposit building up inside the flue.
Posted Thursday 8 Aug 2013 @ 2:34:24 am from IP #
