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sidney alstad
08-06-2015, 05:14 PM
Split system heat pump. No emergency heat setting at any thermosats. There were three thermostats as it had three zones....none had the emergency heat setting. Honeywell thermostat, click on the mode for cool, heat or off. Heat pump was operated in both heat and cool as the temperature was right around 67 F. Anyone else ever see this.

Dom D'Agostino
08-07-2015, 04:22 AM
They make all kinds of t-stats. Was this a new install? Maybe that's all they had on the truck that day...

Was there a zone controller? Many of those have an EM heat function. Also, some T-stats will go into EM mode if you increase the Set Temp 2 degrees above current temp.

Dom.

Garry Sorrells
08-07-2015, 05:49 AM
Are there heat strips?

Scott Patterson
08-07-2015, 05:57 AM
Are you sure they were heat pump units? Check those condenser model numbers and this will tell you real quickly…

Jerry Peck
08-07-2015, 06:47 AM
Are you sure they were heat pump units? Check those condenser model numbers and this will tell you real quickly…

A simple check of whether or not the condenser units are running in heat mode will tell whether or not they are acting as heat pumps - easy enough to do while on the inspection, just like checking the condenser units while the air conditioning is operating.

Mark Reinmiller
08-07-2015, 04:09 PM
Moving the thermostat up 2 degrees (or even 1 degree with digital thermostats) should activate the electric resistance heat, but there should still be an emergency heat setting.

On many of the newer thermostats your have to set up the thermostat based upon what type of system you have. Some have about 10 to 12 options. I came across this with two heat pumps where whoever installed the thermostat did not set it up correctly.

Jim Luttrall
08-07-2015, 05:49 PM
As a previous responder noted, look at the master controller (usually at the AHU) for an emergency button. With a multi zone unit (i.e. more than one thermostat) trying to lock out the heat pump to allow the backup heat to function simply won't work (unless you have REALLY intelligent thermostats).

Nick Ostrowski
08-09-2015, 06:54 PM
Look for the reversing valve inside the exterior condenser unit. 98%+ (my made up figure) of heat pump condensers cos will have a visible reversing valve.