Central Heater Cycles On/Off Before Reaching Set Temperature

[Brita01]

Hello, I'm new to the forum. My central heater stays on for about 1 minute and then cuts off for about 30 seconds before starting the cycle all over again until the set temperature is reached. As you can imagine, it takes FOREVER to heat my house at this rate. I'm also worried about the cost of the constant on/off. What could be the problem? Is it something I can possibly fix myself or am I going to need to call a repairman?

[HayZee518]

what do you fire your furnace with? oil? electric? natural gas? propane?

[paul52446m]

Hello, I'm new to the forum. My central heater stays on for about 1 minute and then cuts off for about 30 seconds before starting the cycle all over again until the set temperature is reached. As you can imagine, it takes FOREVER to heat my house at this rate. I'm also worried about the cost of the constant on/off. What could be the problem? Is it something I can possibly fix myself or am I going to need to call a repairman?

You will have to give us a lot more info. If it is a gas furnace, does it have a pilot? what lites the pilot, Standing pilot with thermocouple, sparker, or glow bar? Have you changed or tried to reset the thermostat, or installed a new stat?
Is the air filter clean? Does your blower come on? Does it have a flame rod in the pilot assembly? Later Paul

[Brita01]

what do you fire your furnace with? oil? electric? natural gas? propane?

It is electric.

[Brita01]

You will have to give us a lot more info. If it is a gas furnace, does it have a pilot? what lites the pilot, Standing pilot with thermocouple, sparker, or glow bar? Have you changed or tried to reset the thermostat, or installed a new stat?
Is the air filter clean? Does your blower come on? Does it have a flame rod in the pilot assembly? Later Paul

It is electric. I need to change the air filter. The blower comes on for a minute, goes off for about 30 seconds and then the cycle starts over again until my house is heated to the temperature I have the thermometer set at. Yes, I have reset the thermometer several times.

The first thing I will try is the change the air filter.

[HayZee518]

ok, being an electric furnace, inside the unit is a bank of heating elements. each bank of elements are controlled by a heat sequencer. the sequencer is controlled by a master relay connected to your thermostat. the first stage will turn on the elements and the fan, the second and/or third sequencer will turn on as it is needed to satisfy the set point of the thermostat. there are interlocks [contacts] that keep the fan running during these switch-overs.

[Brita01]

Ok, so I feel like a complete idiot. I changed out the air filter and now it's working fine. Thank you for the help.

[paul52446m]

Hello, I'm new to the forum. My central heater stays on for about 1 minute and then cuts off for about 30 seconds before starting the cycle all over again until the set temperature is reached. As you can imagine, it takes FOREVER to heat my house at this rate. I'm also worried about the cost of the constant on/off. What could be the problem? Is it something I can possibly fix myself or am I going to need to call a repairman?

Ok it is turning off so we need to start doing some checking. Find the thermostat wires at the furnace. Try jumping the low volt t&t wires and see if the unit keeps working. This will find out if we have a stat or stat wire problem.
Next we would need to find out if the heat relay is staying made. It sounds like the heat relay is your problem. but you would need to know if the 24 volts is being brook going to this relay. You also could have a week limit switch breaking the power to the heat relay. Or the blower fins and filter could be plunged up enough to make the limit open and stop the heat relay because you are not moving enough air through the furnace. Later Paul

[paul52446m]

Ok, so I feel like a complete idiot. I changed out the air filter and now it's working fine. Thank you for the help.

Glad you got it going, we all get caught at one time or another. paul