elecrobot
31-05-2022, 11:14 AM
Hi All,
We have recently moved in a building and trying to troubleshoot issues with the Fan Coil Unit (FCU). Please see details below. If someone can please give some advise based upon your experience, it will be greatly appreciated.
With regards to Fan Coil Unit, what we have observed is as below. Can you please discuss with your technical department to advise:
We have a 4-pipe Fan Coil Unit. There are 2 pipes (flow in/flow out) to heating coil and 2 pipes (flow in/flow out) connected to cooling coil (Cooling coil is not in use and Chiller switched off) within same FCU. There is a manual valve on the inlet to Fan Coil Unit (FCU) heating coil and an actuated PICV on the outlet of the FCU heating coil. We have removed the actuator just to keep the testing simple and check the water flow from FCU is good from the heating coil. Both inlet valve to FCU and the PICV on FCU outlet are manually open for this testing. What we have found during testing is when the FCU is switched off via local isolator switch, inlet and outlet pipework from/to FCU are very hot which makes sense as the water is circulating from the FCU as both inlet and outlet valves on FCU are in open position. However when the FCU is switched ON from the local isolation switch, the inlet pipework temperature remains very hot as before but the outlet pipework temperature drops to normal (slightly warm) after few minutes. My question is what is the temperature difference between the inlet and outlet pipework when fan within FCU is running? The air coming out of the FCU is at good flow but it's only slightly warm which I don't think is enough to warm the room.
We have recently moved in a building and trying to troubleshoot issues with the Fan Coil Unit (FCU). Please see details below. If someone can please give some advise based upon your experience, it will be greatly appreciated.
With regards to Fan Coil Unit, what we have observed is as below. Can you please discuss with your technical department to advise:
We have a 4-pipe Fan Coil Unit. There are 2 pipes (flow in/flow out) to heating coil and 2 pipes (flow in/flow out) connected to cooling coil (Cooling coil is not in use and Chiller switched off) within same FCU. There is a manual valve on the inlet to Fan Coil Unit (FCU) heating coil and an actuated PICV on the outlet of the FCU heating coil. We have removed the actuator just to keep the testing simple and check the water flow from FCU is good from the heating coil. Both inlet valve to FCU and the PICV on FCU outlet are manually open for this testing. What we have found during testing is when the FCU is switched off via local isolator switch, inlet and outlet pipework from/to FCU are very hot which makes sense as the water is circulating from the FCU as both inlet and outlet valves on FCU are in open position. However when the FCU is switched ON from the local isolation switch, the inlet pipework temperature remains very hot as before but the outlet pipework temperature drops to normal (slightly warm) after few minutes. My question is what is the temperature difference between the inlet and outlet pipework when fan within FCU is running? The air coming out of the FCU is at good flow but it's only slightly warm which I don't think is enough to warm the room.