Great video! I have a Daikin 16kw Heat Pump, with 11 fan coils and 3 towel radiators in the bathrooms. Never got a heat flow problem, no buffer. But when I installed it (made the heat loss study myself as a mechanical engineer, but I had no experience with HVAC at all) the shop owner where I bought the HP advised to use Φ25 pipes for the larger fan coils, because in cooling we need unobstructed flow. So that's how we went, Φ25 for the larger fan coils, Φ22 for the medium, Φ18 for the smaller ones. So, with 11 fan coils and so many meters of good diameter pipes, I have enough liters in the system (even with the 3 radiators out, to avoid condensation) the heat pump works perfectly, it modulates between 15 and 30 liters/hr as far as I have seen, with miminal start/stops. I don't have buffer and no 2way or bypass valves on any fan coil (just the fan motor modulates when they reach the set temperature). I am pretty satisfied.
The problem can be that you can need some energy to defrost and normally the coils have less energy to give then. Maybe in 11 fancoils you have enough, but using this system in a cold area for heating, I would reccomend a proper calculation of the energy can give 11 fancoils workin on loses, means low temp - energy. Fo summer it's ok.
Great point there! You need enough energy in the circuit to reverse the cycle and defrost the coil. I have never had such issue, probably it helps that I have many meters of running pipes, as well as long and big diameter main pipes, not 1"!!!
I used to commission industrial units and it was always considered to be poor practice to have two or more pumps on the same circuit without a low loss header or similar and also some form or measuring device (FMD) such a device takes the guesswork out of the equation, heat pumps are a great invention but it is usually it is the installation that lets the technology down. Great vid as is said great food for thought.
@@HVACEducationHub eeehhhh... Methane gas heater ??! Is not nice. When a house go full electric don't use gas anymore. It must be a solution without additional heat pumps.
Great video! I have a Daikin 16kw Heat Pump, with 11 fan coils and 3 towel radiators in the bathrooms. Never got a heat flow problem, no buffer. But when I installed it (made the heat loss study myself as a mechanical engineer, but I had no experience with HVAC at all) the shop owner where I bought the HP advised to use Φ25 pipes for the larger fan coils, because in cooling we need unobstructed flow. So that's how we went, Φ25 for the larger fan coils, Φ22 for the medium, Φ18 for the smaller ones. So, with 11 fan coils and so many meters of good diameter pipes, I have enough liters in the system (even with the 3 radiators out, to avoid condensation) the heat pump works perfectly, it modulates between 15 and 30 liters/hr as far as I have seen, with miminal start/stops. I don't have buffer and no 2way or bypass valves on any fan coil (just the fan motor modulates when they reach the set temperature). I am pretty satisfied.
This is the best setup, thanks for feedback.
Actually the simplest is always the best and, as you mentioned, good pipe diameter.
Just to add, you probably have 15-30 L/min, not per hour
@@HVACEducationHub correct!!!
The problem can be that you can need some energy to defrost and normally the coils have less energy to give then. Maybe in 11 fancoils you have enough, but using this system in a cold area for heating, I would reccomend a proper calculation of the energy can give 11 fancoils workin on loses, means low temp - energy. Fo summer it's ok.
Great point there! You need enough energy in the circuit to reverse the cycle and defrost the coil. I have never had such issue, probably it helps that I have many meters of running pipes, as well as long and big diameter main pipes, not 1"!!!
I used to commission industrial units and it was always considered to be poor practice to have two or more pumps on the same circuit without a low loss header or similar and also some form or measuring device (FMD) such a device takes the guesswork out of the equation, heat pumps are a great invention but it is usually it is the installation that lets the technology down. Great vid as is said great food for thought.
There is hydraulic separation.
Actually primary pump is used for cooling with volumizer but in heating buffer + secondary pump.
How the heat pump manage to make hot water for shower ? Is switching from cooling to heating automatically ?
Usually 3 way valve is switching but here gas boiler is used for hot water
@@HVACEducationHub eeehhhh... Methane gas heater ??! Is not nice.
When a house go full electric don't use gas anymore.
It must be a solution without additional heat pumps.
Natural gas + heat pump combination
@@HVACEducationHub ugly and unholy combination !!
I have heat pump+solar heater. No need the HP to work at all for DHW during cooling season.
Mine froze solid last winter so had boiler installed again . Avoid heat pumps !
Probably there was a problem not related to the unit itself