AHS 130 Question

ahs owner in ny · Post by **ahs owner in ny** » Mon. Mar. 03, 2008 6:14 pm

I recently installed an AHS 130 and today house was not calling for much heat and the boiler temp and pressure went way up. The relief valve went off to release the pressure and not really knowing what to do I opened the doors and windows trying lower the temp in here to get the circulate pump to come on and send water through the house further cooling the system down.

My question is, how do you keep the boiler temp down when your house isn't calling for heat?

I have my aquastat set on 150 and the other stat set to come on at about 120 and go off at about 140.

I will have to call the company tomorrow and see what they have to say but I was hoping some one here might have some advice also.

Thanks in advance for any help!

LsFarm · Post by **LsFarm** » Mon. Mar. 03, 2008 7:00 pm

Hello and welcome to the forum...
You need to increase the air gap between the inspection cover plate and the boiler, to let more air in over the fire.. this gap should be at least 1/2" to 3/4"

And if you don't have a barometric damper installed, install one.. if you have one installed, make sure it is working correctly [the door swings freely] and the draft is set to the correct setting, I think it is supposed to be .04" wc.

If the inspection plate is set too close, and the draft is too high, the plate can get sucked shut by the draft, which will pull a draft through the fire, making heat even when the aquastat is not calling for it.

The AHS, AA and Eshland boilers will work very well as a domestic hot water heater year round.. once they are set up correctly. They will idle along, with the timer running the combustion fan [and ashing motor] every hour to keep the fire alive, and the aquastat calling for heat when the domestic hot water is used.

Hope this helps.. Greg

Sting · Post by **Sting** » Mon. Mar. 03, 2008 7:03 pm

Greg,

Would you recommend a "heat dump" on all solid fuel boilers?

U235a4 · Post by **U235a4** » Mon. Mar. 03, 2008 7:14 pm

another thing to look at is your expansion tank, which is most likely two small. you need a bigger one but check the pressure on yours first and make sure the air pressure is what the system pressure is supposed to be. aka if your system is 12 cold them when that boiler is at max temp for AA's that would be around 230F your pressure should be only two PSI higher (14). Now to check the air in the bladder if it is a diagram type you need to remove it from the system to make sure the water is drained out and then you can check the air.

LsFarm · Post by **LsFarm** » Mon. Mar. 03, 2008 7:18 pm

I planned for one in my system, when I was going to use wood as the fuel.. but once I started using coal, I found that coal was much more controlable than wood, and I didn't need a heat dump.

My Axeman Anderson 260 controls the water temperature very well, I have the water set at 180*, and I rarely see an overshoot of more that 5*. So I have no need for a heat dump system.. at least for now.. If , in the warmer weather, I start getting more of an overshoot, I'll just lower the water temp to 150* or so...

Other stoker designs are not able to reduce the fire a well as the AA boiler does, so a heat dump system may be needed, but I think it will depend on the instalation and the particular boiler.

Greg L

Bob · Post by **Bob** » Mon. Mar. 03, 2008 10:18 pm

LsFarm wrote: The AHS, AA and Eshland boilers will work very well as a domestic hot water heater year round.. once they are set up correctly. They will idle along, with the timer running the combustion fan [and ashing motor] every hour to keep the fire alive, and the aquastat calling for heat when the domestic hot water is used.

The current model of the AHS 130 boiler does not include a timer. However, one can be added relatively easily.

Yanche · Post by **Yanche** » Mon. Mar. 03, 2008 10:22 pm

As U235a4 has suggested look at your expansion tank and your water feed regulator valve. Remove the tank, drain any water in it and set the air side of the tank to 12 psi. When you install it add a valve, one with a bleed port. Install it so the bleed port it toward the tank. Then in the future you can check or set the pressure by closing the valve and opening the bleed port. The valve should have the handle wired in the open position. You don't want it ever closed while the system is in use. You can use less than 12 psi pressure if you only have a single story house, or will need more if you heating three stories. What ever pressure you choose, the regulator pressure should match.