Follow up on greenhouse heating. I have a lean to greenhouse with a concrete radiant floor. I had planed an on getting demand heater but based on building codes I had no where to vent it. At the same time had a water heater failure and installed a mini Weil McClain furnace that makes hot water for my domestic use and sends a line to the floor of the greenhouse. The heater has two outlets off the main pipe. Heater water runs through a super insulated tank and heats water for kitchen and bath and the other line heats the greenhouse floor. There are two thermostats that can turn on the min furnace. The control valves are on the return side of the system. Hot water leaves the furnace at 160 F and goes where it is needed. Considering I added and 7 by 12 foot greenhouse the utility bill has decreased due to the efficiency of the system. I have a backup[ up electric heater in case of a heater failure. Arnold -----Original Message----- From: Robert Lauf via pbs <pbs@lists.pacificbulbsociety.net> To: Judy Glattstein via pbs <pbs@lists.pacificbulbsociety.net> Cc: Robert Lauf <boblauf@att.net> Sent: Sun, Oct 31, 2021 10:53 am Subject: Re: [pbs] Greenhouse Heater Issue Wow. Truly the perfect storm! It's time to think about lighting the pilot on my vent-free heater and I usually need to take off the front and blow compressed air around the pilot to get out the summer's accumulation of airborne debris that clogs the little vent holes. The vent-free heater hangs on the brick wall of the house and was about $300 from HD back in the day. Basically 100% efficient but I can only get away with it because I'm the on the city (natural gas) line. Propane will produce traces of ethylene and the orchids don't like it. If anyone knows whether bulbs are damaged by ethylene, that would be good info to share. I've been told that a tomato plant is a great indicator to test for ethylene because it is extremely sensitive to low concentrations. Bob E TN where the fall colors are getting nice. Frost will be a few weeks away, so it's time to start moving things back into the already-full greenhouse. _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/… Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net> _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/… Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net>