6/10, 10/16, 16/22, MkI, MkIIF, Electronic
One of Potterton's better efforts in my opinion. If you have one in good
condition, it's well
worth looking after.
A ground-breaking design originating in the late 1970's. One of the first (if
not THE first) ever to have automatic spark ignition instead of a permanent
pilot light, and a fan assisted flue. A major improvement in
fuel-efficiency by forward-thinking designers in the days of plentiful north sea gas when no-one
much cared about such things. An ordinary, natural draught boiler turns into a
radiator heating the great outdoors when the burners are OFF through natural
convection. Potterton decided to design a boiler that didn't do this, and
therefore needed a powered flue. The NetaHeat was the result. 78% fuel-efficient
in the days when 55% was typical, and many are still in use today.
NetaHeat Mk I (10/16 and 16/22)
A fan-flued boiler with NO electronics (well
ok, there IS a simple electronic spark generator, but that's all). Excellent!
All the main controls are electro-mechanical or plain mechanical. Very
unconventional by today's designs, and almost impenetrable. I did manage to
reverse-engineer the start-up sequence years ago when spares were available and
I have a Word file of it for fault diagnosis should anyone need it. Email me if
you do. Little point though as all the major control components are now obsolete
and unavailable. If you have a MkI Netaheat the only commonly failing parts
still available are the flue fan and the boiler thermostat. A great boiler
though if yours is still working.
NetaHeat MkIIF (10/16 and 16/22)
Similar in appearance to a MkI and with the
dame heat exchanger and fan but completely different and much simplified control
components. A conventional combined multi-function gas valve now instead of
separate components for each function. Little to go wrong with this boiler
except the fan, thermostat or gas valve, and amazingly for a boiler discontinued
20 years ago, today all three of those parts are still available.
NetaHeat Electronic (6/10, 10/16 and 16/22)
A truly modern boiler. Still
the same heat exchanger and fan as the earlier versions, but with full
contemporary electronic control. The boiler all the other manufacturers
eventually copied. Simple to fault-diagnose and repair, but sadly the gas valve
is no longer available. All other parts are though. Common faults are fan
failure, control board failure, erosion of the earth electrode on the pilot
ignition. Gas valve failure is less common but still happens. No option other
than to replace the boiler in this case.
these NetaHeats are 'positive case pressure' boilers. This means the fan blows
fresh air into the case and consequently, it is crucially important for the case
to be correctly fitted and airtight. Crucial because there have been a number of
deaths associated with the case not being fitted correctly. If the case is not
fitted correctly inadequate air is supplied to the burners, leading to carbon
monoxide in the combustion gas which essentially leaks out into the house
through the gaps around the incorrectly fitted case. The importance of fitting
case correctly is often not appreciated by people DIY-ing their boiler
servicing, unqualified plumbers etc, and multiple user deaths eventually lead to
this boiler being withdrawn from sale. The NetaHeat is a perfectly safe boiler
when the case is correctly installed though.
A new boiler with 'negative case
pressure' was introduced by Potterton to replace the NetaHeat. The "NetaHeat
Profile" is a completely different boiler, just as good, but without the
risks associated with incorrect case-fitting. The NeatHeat Profile will simply
not run if the case is not correctly fitted. The "NetaHeat Profile"
was later renamed to just "Profile". A first class boiler in my