Advice on Power Venter? - Contractor Talk - Professional Construction and Remodeling Forum

BreyerConstruct · 12-21-2006, 02:05 PM

I've got an old house with an old furnace. It's oil fired hot water radiators.
The exhaust goes out a chimney on the side of the house.

The oil company I use came today for the annual clean & tune up of the furnace, and they checked the draft. In the past, it's been barely negative, and it's now just slightly positive.

The chimney had partially collapsed internally when we renovated this house (brick chimney) about 3 years ago. There was a liner in the chimney, but it only went part of the way up. We opened up the chimney 1/2 way up, cleaned it out, and re-lined it up from there. I should probably explain that the chimney starts on the inside of the house, goes 1/2 way, then finishes the run on the outside of the house. The place it had broken down was at that kink.
I can only guess that that area has deteriorated again.
I'm guessing I can tear into the chimney & repair it- but if it's only going to be marginable...
So, they're supposed to be working me up a price on installing a venter, & whatever other options there might be.

I'm all ears if you've got an opinion or thought!
Thanks.

~matt

QWIKWHIP · 12-21-2006, 04:56 PM

You have a few choices here. With your existing atmospheric vented boiler I highly reccomend to stay far away from add on power venters. Especially on fuel oil. They are a high maintanance item. They require oiling and cleaning at least a couple times a season and expect to replace the motor every 3-5 years. If it was me, I would look into repairing the chimney. If the chimney is structurly sound, then have a liner put in. If the chimney is shot, then I would either rebuild it or replace it with a proper S/S chimney. Power venters are nice as a last resort, but I would never reccomend one. However, defenitly don't confuse an add on power venter with a power vented boiler.... that's a whole different game. If the boiler is old, you may want to look into replacing it with a power vented one. I recommend the Burnham MPO. That's a sweet boiler.

pitman9 · 12-22-2006, 04:51 PM

We have a number of the SS1 and SS2 units out there. They do have their quirks but our experience is they are far more reliable than the Field PV, especially for oil.

The SS1 blower wheels seem to go out of balance. They're a squirrel cage type of wheel. The SS2 wheel looks more like a car water pump impeller. The only problem we've had with the SS2 is the pressure sensing tube has plugged on a couple of units. Other than that they've been very reliable. BTW, our clients tend to service their equipment annually and that may help.

AirPro · 12-26-2006, 04:34 AM

It sounds to me like you need to replace that furnace and convert to gas or a dual fuel system. Positive flue pressures result in only one thing that you should be concerned with....CO poisoning, please get this fixed ASAP.

BreyerConstruct · 12-26-2006, 07:52 AM

Here's an update:

We opened up the chimney 1/2 way up. This is the location we knew was tight on the flue & had a double bend in it )chimney goes from outside to inside the house wall).

It turns out that when we bought the house & initially got the chimney working 3 years ago we replaced the missing liner with galv. Wow does that stuff disappear quickly! This had discinigrated & blocked up the flue @ the 90's.

It's vented out the side via a new 90 right now- as we didn't have time to complete the project before Christmas. However, there's 14' of new stainless 6" pipe in my shop, and it will be slid down the chimney, connected & sealed in the next few days.

Right now the furnace seems to be working well; I have installed 2 extra smoke detectors & a CO detector in the house, just in case!

Thanks for the advice & thoughts here! I was hoping to keep the furnace (85% eff.) & just repair the chimney, so I'm encouraged at the outcome.

Thanks again,
~Matt