Pump problem?

Is the thermostat set to cooling rather than heat? If it is a simple two-wire thermostat, all it does is connect the two when it needs heat.

It is a simple two-wire thermostat and does not have a cooling feature. The problem is when it should require heat it is not triggering the pump to send hot water unless it is turned up high. I thought I should be able to have hot water running through my baseboard even when it is set lower. I just bought this house and I'm not very familiar with this kind of setup

when those old mercury t-stats get old they are not real reliable anymore id change it out for a new digital one.youll be happy you did just remamber to shut off the power before you change it out.

Yep, sounds like the thermostat bought the big one...

In most cases, the pump is wired so that when the boiler temp reaches a certain temp(anywhere between 110 -120 degrees F), it will be activated. When the boiler water temp comes down below the 110 F, it will stop circulating, giving the water in the boiler a chance to reach a desired temp, eg: 110-120.

The pump is only directly connected to the boiler water temp, not the room temp (where the stat is)

It all depends how your boiler is wired in relation to your pump and where the hi & low limits are set