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Jeffrey
Call for hot water / oil furnace problem

Hi Folks,

New homeowner here. We have a 20+ year-old oil furnace with no separate water tank. Steam radiators throughout the house. I'm guessing there's a coil or something inside that heats the water. It fires (in theory) whenever we need hot water. Recently the call for hot water from our shower is no longer triggering the furnace to fire up. I've found a work-around when we need to shower, and that is to kick my thermostat up a couple degrees, which quickly causes the furnace to fire up, and then we enjoy our scorching hot water in the shower. Why won't our shower trigger the furnace? Who should we contact (the oil man? plumber?) to look into this?

Thanks,
Jeff

Blue RidgeParkway
Re: Call for hot water / oil furnace problem
jmberg wrote:

Hi Folks,

New homeowner here. We have a 20+ year-old oil furnace with no separate water tank. Steam radiators throughout the house. I'm guessing there's a coil or something inside that heats the water. It fires (in theory) whenever we need hot water. Recently the call for hot water from our shower is no longer triggering the furnace to fire up. I've found a work-around when we need to shower, and that is to kick my thermostat up a couple degrees, which quickly causes the furnace to fire up, and then we enjoy our scorching hot water in the shower. Why won't our shower trigger the furnace? Who should we contact (the oil man? plumber?) to look into this?

Thanks,
Jeff

Whomever you'd call upon to service and maintain your boiler system.
You may find this web site helpful (start with the Systems tab): http://www.heatinghelp.com

NashuaTech
Re: Call for hot water / oil furnace problem

jmberg:

could you post back to advise if you have a steam boiler or hot water boiler.

A hot water system has little bleed valves on the TOP of the radiators---a steam system has vent valves in the MIDDLE of the rads from which you can hear steam escaping when the system heats up; it also has a glass water level tube on the front of the boiler.

Jeffrey
Re: Call for hot water / oil furnace problem

Definitely steam radiators, with the glass water level tube on the front of the boiler.

NashuaTech
Re: Call for hot water / oil furnace problem

jmberg:

You can call your oil man if he/she is familiar with steam systems--otherwise you would have to call a heating contractor who is familiar with a domestic hot water takeoff zone from a steam boiler.

Experienced steam technicians are not that common these days, so you may have to call several techs before you find one that knows how to work with this type of equipment.

A zone is usually set up below the condensate water line & controlled by an aquastat, circulator pump and heat exchanger, as noted in the sites below.

You've probably had a failure in one of these components (especially the pump or aquastat relays), which is why you don't have ready hot water available for cleaning/washing---but also check the piping near the boiler on the domestic hot water line for any TEMPERING VALVE, which may have frozen shut/failed due to old age.

http://www.heatinghelp.com/pdfs/346.pdf
http://www.heatinghelp.com/heating_howcome6.cfm
http://www.heatinghelp.com/newsletter.cfm?id=29

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