I have a 24v Tecma EasyFit Eco head (actually, a pair of them). Mine
lack the fancy control that lets you just touch a button to fully flush
and refill the bowl; instead I have a simple momentary-momentary rocker
switch. Push one way to add water, push the other way to run the
macerating pump, which also flows water.
The innards are dead simple: a macerating pump, which has exactly two
wires, and a water solenoid, which also has two wires (it's a fresh
water model, connected to house pressure). To my mind, all that's needed
to run this is the switch, and a power relay to run the high-amp (40a)
pump from a low-amp switch.
Nevertheless, Thetford have seen fit to equip the unit with a circuit
board. The aforementioned power relay, a simple SPDT model from Tyco, is
mounted to this board, and the entire board is potted. I have no clue
what, if anything at all, the rest of the board does. Polarity
protection? Perhaps some function only relevant with the fancier
self-timing control? (I believe this board is common to both models.)
In any event, one of my boards failed. A new one is north of $250 and
I'd need to find a way to get it sent to me. Which has me wondering --
do I even need it, or can I get by with a power relay and a few bits of
wire?
For the curious, the failure on my board is that it is providing power
to the pump full-time regardless of switch position. Possibly the relay
contacts have self-welded. It would appear the failure was initially
caused by a temporary pump jam. Percussive maintenance on the relay was
unsuccessful. I've temporarily worked around the problem by adding my
own relay in series with the stuck one, operated by the same switch.
Can anyone more familiar with these than I tell me what, exactly, that
control board does or is supposed to do?
-Sean
m/y Vector
under way to NY harbor in the Atlantic
http://OurOdyssey.BlogSpot.com
I have a 24v Tecma EasyFit Eco head (actually, a pair of them). Mine
lack the fancy control that lets you just touch a button to fully flush
and refill the bowl; instead I have a simple momentary-momentary rocker
switch. Push one way to add water, push the other way to run the
macerating pump, which also flows water.
The innards are dead simple: a macerating pump, which has exactly two
wires, and a water solenoid, which also has two wires (it's a fresh
water model, connected to house pressure). To my mind, all that's needed
to run this is the switch, and a power relay to run the high-amp (40a)
pump from a low-amp switch.
Nevertheless, Thetford have seen fit to equip the unit with a circuit
board. The aforementioned power relay, a simple SPDT model from Tyco, is
mounted to this board, and the entire board is potted. I have no clue
what, if anything at all, the rest of the board does. Polarity
protection? Perhaps some function only relevant with the fancier
self-timing control? (I believe this board is common to both models.)
In any event, one of my boards failed. A new one is north of $250 and
I'd need to find a way to get it sent to me. Which has me wondering --
do I even need it, or can I get by with a power relay and a few bits of
wire?
For the curious, the failure on my board is that it is providing power
to the pump full-time regardless of switch position. Possibly the relay
contacts have self-welded. It would appear the failure was initially
caused by a temporary pump jam. Percussive maintenance on the relay was
unsuccessful. I've temporarily worked around the problem by adding my
own relay in series with the stuck one, operated by the same switch.
Can anyone more familiar with these than I tell me what, exactly, that
control board does or is supposed to do?
-Sean
m/y Vector
under way to NY harbor in the Atlantic
http://OurOdyssey.BlogSpot.com
