I have a client who has a lovely wooden house with underfloor heating.
In the summer I restored his Steinway grand Duo-Art player action and
upon installation everything was fine.

In October the heating system was turned on.  It is an underfloor
system, and some weeks ago he contacted me to say that the player had
lost power.  During my service visit I checked everything, but could
find no visible or cause of leakage.  There was no doubt, however, that
it had indeed lost power.  Whilst working beneath the instrument I did
notice that my back was getting very warm from the wooden floor.

My diagnosis, therefore, is that the pouches have dried out and shrunk,
and I plan to remove the valve chest for further examination.  The
original pouches were in excellent condition, and I felt it unnecessary
to replace them.  This may have been unwise, but performance upon
completion was excellent.  It may well be that if I replace them now
they will also shrink in future due to the rising heat.  Does anyone
know how to prevent re-occurrence?

A tube humidifier hung below the valve chest seems one possibility.
A carpet on the floor may help, but I would appreciate any and all
advice.

Roger Waring - The Pianola Workshop
Solihull, West Midlands, UK
http://www.pianola.co.uk/