25deg in the cabin tonight, 9 o’clock on the volume 40mins in. Nice fan sound coming from the corner. Starting to wind down now after 5 mins. And stopped.
Just thought you might be interested. 
On with the show.
2 Likes
Cabin?
Log cabin top of the garden. No aircon 
2 Likes
Ah, sounds nice!
…but 25c is what I set the aircon to in summer to cool down. That is until Mrs. FZ says it’s freezing and sets it to 28c.
I never had any issues running Naim in a hot room. My 250 doesn’t have a fan but has a thermal trip, which I’ve never hit.
25deg cool! You must be in a warm neck of the woods. This is a heatwave where I am. 25deg is what the cheap thermo readout says so it’s probably a bit warmer. My old 250 used to trip regularly on those hot summer nights which is one of the ways I justified the 135s with their fans.
How long has it been since your 135s were serviced?
I never managed to get the fans to switch on with our NAP135s and we tried, we really tried on a number of occasions, usually when Deep Purple were involved on the turntable…
If the fans are cutting in when the pre-amp volume knob is at 9 o’clock, I’d take that as a gentle hint that something is needing a service.
Good luck, BF
5 Likes
As far as I’m aware, I’ve had the fans on in the 135s once in all the time I’ve owned them, but to achieve that I had to leave the room because of the volume. This was with SBLs and I was testing out the bass. Presumably there are speakers that will cause the fans to come on more readily.
Serviced 2018 but I realised the temp,was nearer 30. Pressed the wrong button. 9 o’clock is pretty loud using the NDX whereas I push it to 10-11 using the LP12 (Prefix) so the gain on the NDX din is much higher than the Prefix. Speakers are Keilidhs (4 Ohm). It’s the first time I’ve heard them kick in this year so don’t think anything sinister is going on. Maybe the pots on the fan boards are set a little sensitive but id be more worried if they never kicked in to be honest.
You didn’t leave voluntarily, you were ‘blown away’ by the fan.
1 Like
I remember mentioning this to JV himself > he said just stand the PA on their side
2 Likes
NAP135 fans are set to activate at 42 degrees C at the heatsink. The environment you describe sounds completely normal.
The “I need a service” symptoms are usually a fizzing distortion in the midrange, followed by “frying bacon” distortion when sat idle.
Regards
Neil.
I should have added, that oscillation (needs a service) will indeed make an amplifier work hard & create heat.
5 Likes
And not the bass 
On my previous pair of nap 135s the left channel fan triggered even though it was sitting on the same rack as the right channel with plenty of ventilation. Strange but it only happened once a few summers ago. I think perhaps the draft of wind was only reaching the right channel.
I think it’s unlikely that both fans would kick in exactly at the same time anyway. Each will be set slightly different. I imagine that when serviced the fan board pot is turned fully one way just to check that the fans are actually working then returned to the “Middle” position. As long as they come on all is good. And the fans coming on means summer has arrived for me in the same way as my old 250 tripping out did previously. I’ve got to say my environment is probably more prone to temp variation being a log cabin in the garden so I guess many will not experience this phenomenon.
I dont think I have had one fan go on from my 135’s. Possible too quiet to notice with BR, PJ and video processor fan. But II do go to reference volumes and play at good levels
I had a 250 and swapped them for a pair of 135s quite a time ago. Well before the Fraim and the current way of thinking. The 135s were under a big record cabinet on the floor. This time of the year towards the end of the evening the fans would have cut in.
Not quite - the heatsink temperature is monitored through a dedicated hole in a generic cover while driving a 300Hz signal into the amp at a 2 ohm load. The fan trigger point is 42 degrees C & the fan is expected to stop at around 44 degrees*. Anything outside of the trigger point requires a tweak of the pot & a repeat of the procedure.
We don’t do things by half at Naim!
*After the load is removed.
Regards
Neil.
6 Likes
36C ambient tonight. 52 vol at zero so no load. Fans are already spinning on low (Assume multi speed). This is a first for me (in U.K.) I guess it’s a case of whether the Naim kit can outlast me tonight. Let’s give it a go
I wonder how many 250s are tripping out tonight in the U.K.?
2 Likes
Well 52 remotes given up the ghost. Maybe batteries. It’s 30+ years old so I forgive it.