Hot Water System

Hot Water System FAQ:


I have installed a Honeywell RTH230B 5-2 Day Programmable Thermostat, which allows a cycles per hour (CPH) setting to be programmed in. The furnace is hot water with a gas burner, no pump, no zones, and cast iron radiators (i.e., very old). Honeywell tech support from India had no clue–only read from the manual, which lists “hot water” and “gravity” separately, with 3 and 2 CPH respectively. This system would likely be called “hot water-gravity” right? Thanks.
Just to clarify, it is definitely a hot water system, with two pipes per radiator, and an expansion tank on the basement ceiling above the furnace.

Hot Water System FAQ:


I have a tankLESS water heater system in my house. I have been having trouble with my pressure relief valve leaking every time the boiler turns off after firing to heat the water. I had my HVAC repair man over twice and he replaced the valve both times and it still leaks. Any ideas at what might be causing this? I had an idea it could be air in the system somewhere, or a water-logged expansion tank. I have 5 zone hot-water baseboard heat.

Hot Water System FAQ:


This is a forced hot water by natural gas system. The overflow valve is located above the top of the boiler and comes off the extension that the expansion tank is connected to. Replacing the valve is fairly simple. I just need to know that by shutting off the water intake will prevent any water leak while I am replacing the valve. Or will I need to drain the whole system ??