tbarker3440
New Member
I have a NTI Matrix with a m100v condensing boiler that heats forced air, domestic hot water and in-floor heat.
It is at the start of the 7th heating season and I have replaced the stack limit switch 3 times. The manufacturer says the ruined switch indicates water in the vent. It is plumbed with 3" PVC. There is condensation inside the pipe when looking into it from outside (It runs up 5feet and then horizontal for about 12 feet and exits through the rim joist). I am certain that I should not be having to replace this so often. I also thought that condensation is normal in the vent pipe. It is sloped to allow the water to drain back into the boiler and ultimately out the condensate drain. How could water ruin the stack limit switch? What could be changed to stop this?
The primary loop of the boiler has a copper water supply fed through a 15 psi reducing valve and a ball valve. There is no one-way check valve before the pressure reducer.
Should the ball valve be normally closed and thus keep the primary loop isolated? ie only open it manually to top up the pressure if required? There is a pressure guage on the primary loop and there is a pressure safety switch on the primary loop manifold.
This is the first season that I can hear noise in the primary loop. It sounds like scale is circulating. Can someone point me to a reference on flushing it? Can't find one from NTI. I am specifically wondering if the built in circulator pump is active during a flush? Will using an external pump to circulated water through the loop push water through a non-running pump?
Thanks for any help. I am in a small northern town where one does not just call the local certified, expert, fully qualified, < insert-trade-here>. I have had a lot of trouble with this device ( two factory parts replacements for faulty electronics, and several small installation errors) and I have managed to get everything sorted out myself so far. Just looking for a few things to keep it going forward.
It is at the start of the 7th heating season and I have replaced the stack limit switch 3 times. The manufacturer says the ruined switch indicates water in the vent. It is plumbed with 3" PVC. There is condensation inside the pipe when looking into it from outside (It runs up 5feet and then horizontal for about 12 feet and exits through the rim joist). I am certain that I should not be having to replace this so often. I also thought that condensation is normal in the vent pipe. It is sloped to allow the water to drain back into the boiler and ultimately out the condensate drain. How could water ruin the stack limit switch? What could be changed to stop this?
The primary loop of the boiler has a copper water supply fed through a 15 psi reducing valve and a ball valve. There is no one-way check valve before the pressure reducer.
Should the ball valve be normally closed and thus keep the primary loop isolated? ie only open it manually to top up the pressure if required? There is a pressure guage on the primary loop and there is a pressure safety switch on the primary loop manifold.
This is the first season that I can hear noise in the primary loop. It sounds like scale is circulating. Can someone point me to a reference on flushing it? Can't find one from NTI. I am specifically wondering if the built in circulator pump is active during a flush? Will using an external pump to circulated water through the loop push water through a non-running pump?
Thanks for any help. I am in a small northern town where one does not just call the local certified, expert, fully qualified, < insert-trade-here>. I have had a lot of trouble with this device ( two factory parts replacements for faulty electronics, and several small installation errors) and I have managed to get everything sorted out myself so far. Just looking for a few things to keep it going forward.
