Sentinel Kinetic Plus B summer bypass doing nothing

[diarmidR]

Hi all, the summer bypass on our Sentinel kinetic appears to be giving the same inlet temperature as the normal heat-exchange operation. House at 22C, external at 14C and in-flow at vent at 21C in both modes.

 

Has anyone else observed this lack of any temperature drop upon opening the bypass?

 

Ta, D

[Jolo]

In most MVHR units I've seen, the incoming air always flows through the exchanger, it's the exhaust air that flows directly out in bypass mode. So it can take a short while for the heat exchanger to cool down. I assume you've given it time to cool, but I just thought I'd mention this! Another factor to consider is that if the fabric of the house is warm, then the ducting will also be warm, which I find can heat the air up a little as it travels to the vents. I don't know that this would make such an increase as you describe, but it's worth bearing in mind.

 

It might be worth checking that the bypass actually is open too. For example there's an software bug on my Duco MVHR which closes the bypass when the outside temp is below 15°C in "auto" mode, even if the target temperature is set to 10°C! (According to the manual, this forced closing of the bypass is only supposed to happen below 10°C outside temp.) I'm waiting to hear back from them about a software update, but in the meantime I set the bypass mode to "open" instead of "auto" to prevent it from warming up the incoming air.