Pump distance from Boiler?

[EricO]

So I searched old forums but wasn't able to find an answer.

My question is: Is there an acceptable distance for the circulator pump to be from the boiler?

For example, I have my boiler in a garage 100 feet from the house, would it be to far to put the pump on the supply side once it enters the house (Essentially 100 feet downstream of the boiler)? The expansion tank would still be in the garage, I was just thinking of putting the pump in the house for wiring considerations.

The supply line would come into the house and then go through a baseboard heating system.

 

[ewdudley]

With a long run you would more than likely need to have the expansion tank tee in just upstream of the pump, not 100 feet away. You could run some light-gauge 24 VAC direct-burial wires to control a relay in the garage.

 

[peakbagger]

With pumps if you are pushing liquid the location doesn't really make a difference. If you are pulling hot liquids a long distance you can run into issues if you pull a vacuum on the line. There is a calculation called Net Positive suction Head that has to be done to insure that the NPSHR of the pump is less than the NPSH calculated. On a closed loop system this calculation would rarely be needed.

 

[BoilerMan]

With a long run you would more than likely need to have the expansion tank tee in just upstream of the pump, not 100 feet away. You could run some light-gauge 24 VAC direct-burial wires to control a relay in the garage.

I too would put the circulator in close proximity of the expansion tank. Either both in basement or both in boiler room. Always pump away from the expansion tank no matter where the location.

TS

 

[EricO]

I too would put the circulator in close proximity of the expansion tank. Either both in basement or both in boiler room. Always pump away from the expansion tank no matter where the location.

TS

So would it matter then if the expansion tank is 100 feet away? I could put it in the basement too.

 

[BoilerMan]

The best location for both expansion tank and circ is on the boiler supply in the boiler room. You want to circulator to push water (add pressure) in the direction of the greatest flow restriction. In your case that is the underground (both ways). Are you injecting boiler water into your house system? If so, I'd put the circ on the return in the basement after the expansion tank. Pump toward the boiler in that case. Why not just put circ in the garage? As EWD stated put your pump relay out there and simply run low voltage wire to control it.

TS

 

[stee6043]

Let's not forget that location DOES matter if you only have one circ pump and you have a recirc/mixing loop on your boiler.

I didn't catch what kind of boiler the OP is running. But if he has a recirc/mixing loop at the boiler (near boiler piping) the primary circ pump needs to be inside that loop or it will not work when the boiler is cold.