Matt_B

Yes, exactly - I think that’s my next step. The manuals are just so poorly written though that it’s hard to know how to connect these things up. Anyway, glad the manual helped. If nothing else, it’s up on the web now in case I lose my own copy. If I get to the root cause I’ll post an update. Just need to get through another sweltering summer (with full heat recovery in operation!).

Thanks for the quick reply Dave. I hear the click but alas not the whir whir... I’ve had the thing installed now for 10 years and it’s always been stinking hot in Summer. I thought it was due to the intake being on a south-facing wall, but I’ve gone to the trouble of moving it to the west and it’s no better, hence my review of the wiring. I’ll have to keep trying different combinations. Worst case, I’ll rig up a temporary (external to the box) inline duct fan and route the intake direct to the to supply, bypassing the lossnay altogether for this summer for the inflow, and then revisit when it’s cooler up there in the loft. I’ve just scanned my paper manual doc and will attach. It’s the one which came in the box when I bought it. Hope it helps. 2020-04-26_134952.pdf Forgot to add, in terms of circuit board, it’s exactly as per InchByInch’s. I’ve a 4 position rotary switch wired via cat6 wire to the airing cupboard. I keep it on the lowest speed in Winter (trickle) and the next speed up when it warms up. It’s a largeish house (4000 sq ft) - albeit it’s piped to upstairs only - and I never need the higher speeds. Wiring for the bypass is via the same cat5 to a toggle switch, but as far the lossnay end of things..well, I’m struggling with that as above :).

Hi. I’ve got one of these but in Kingspan form. The circuit board is as-per InchByInch’s. I’m trying to get the summer bypass working but am having no luck. I’ve tried connecting TM2 Com to the last (blank) entry on TM3 (per ProDave’s suggestion) and whilst I get a healthy relay click or two from it, the air remains as if heated through the core. I’ve tried various other combinations on TM3 but to no avail. Can I ask, for those who have it working, do you hear anything positive (like a whirring) from the baffle/bypass motor - i.e. is it obvious to you the bypass has moved into place? Also how quickly does the air temp start to drop after activating it? I note above that PeterW has uploaded a manual for the Mitsubishi-branded variant, but it’s a slightly different manual to my paper one (branded Kingspan). Crucially, the bypass wiring is slightly different. I’ll upload it when I get chance in case it helps others. Anyone any ideas what to try next? Without clear unambiguous instructions (my manual is poorly written) I may have to wait until Winter when the loft cools and strip it all down to see what’s going on.