Friday, March 13, 2009

Fireplace trouble

We had a gas insert put in our fireplace last year. We didn't really do it in anticipation of the new BAAQMD fireplace regulations, but because of Scarlet's lung problems. Burning wood was just too smokey in the house for her. We're fairly satisfied with the new insert, but it came with a remote control made by Acumen that really sucked.

First, some background.

A gas insert is not unlike a gas furnace. There is a standing pilot which heats a small thermocouple. The thermocouple serves two purposes: the voltage it produces holds open the valve supplying the pilot flame (so that if the pilot goes out, the gas supply for it will be cut off), and it also is the power supply for the burner valve. Close a switch and the valve opens and gets lit by the pilot. In old fashioned furnaces, this switching was done by a simple thermostat based on a bimetallic strip.

The thermocouple is only capable of producing a few hundred millivolts, though, so if you want to do something more sophisticated, the control mechanism (whatever it is) will need to be self-powered. This is unlike most central HVAC systems today that use a 24 VAC circuit to power thermostats. There are so-called battery eliminator circuits or remote controls that can be powered off the thermocouple. More on that later.

In our case, our gas insert actually also has an electrically powered, thermostatically controlled fan. Whenever the flame is on and heats the box up to a certain temperature, the fan kicks in. The fan is powered off an outlet we had installed actually inside the fireplace itself. Given this state of affairs, it's only natural that our remote control system would have had a receiver that simply plugged in to the AC outlet.

Guess what.

They supplied us with a receiver system powered by 4 AA batteries, plus 3 AAA for the remote. Not only is that a lot of batteries to have to deal with, but it seemed like it wouldn't go more than a month or two before petering out. I did some research on the Internet and discovered the battery eliminator solution, but though Skytech did make a 6 volt battery eliminator, it didn't work on our Acumen receiver. I'm not sure if it's because our receiver was bad or whether they're all like that. But in any event, it was dismissed.

In its place, I installed a Skytech 5310. Yes, it's got a Jetsons remote, but that's not why I chose it. It was just about the only model I could find out there that had a plug-in receiver. No more batteries ever.

Anyway, ripping out the old receiver and installing the new one was a snap. Just a pair of push-on spade terminals. There was only a single outlet in the fireplace, so I added a "Y" cable so the existing fan and the remote could plug in. That's all there was to it.

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