Chimney liner

chickengirl

Hello, thank you for taking a look at my question. I have three appliances which are two gas boilers and one hot water heater. We have a chimney height of 35 feet, can you please let me know what size chimney liner we should use Whether it would be a 6 inch or 7 inch for multiple appliances. Also wanted to add that one of our gas boilers vent pipes are 7 inches wide. Does this mean we have to go with a 7 inch liner? 

I have included pictures of each appliance tag.  Thank you th

thank you
chickengirl-

Robert O'Brien

168, 000 Btu/hr input on oil boiler
125,000 on gas boiler
40,000 water heater
333,000 total input
Check a chimney chart and that is your answer but 7' at a minimum

WMno57

I don't have an answer to your question, but someone here will.
side note: You can replace the water heater with an indirect water heater that is heated by one of the boilers, or get some type of electric water heater. Then you only have to size the chimney liner for the two boilers.

realliveplumber

The water heater is like 6 months old.

EdTheHeaterMan

WMno57 said:

I don't have an answer to your question, but someone here will.
side note: You can replace the water heater with an indirect water heater that is heated by one of the boilers, or get some type of electric water heater. Then you only have to size the chimney liner for the two boilers.

@WMno57 is suggesting that someone spend some money on new equipment. I think he might be offering to pay for it too. I know he would never suggest something like that without knowing that you may not be able to afford such a luxury as to discard a perfectly good 6 month old appliance without offering his unlimited wealth for your needs.

Lets all thank @WMno57 for his generosity.

Seriously... Is the WM SGO-4 boiler still fired by OIL? or has it been converted to a gas burner?
There may be some controversy as to venting two different fuels into the same chimney. Personally, I have done just that with success, but some AHJ frown on the practice

You can not use aluminum liners with Oil Fired Appliances and it appears that with the total BTU capacity listed you may need a 8" liner if you are using a flexible corrugated pipe liner. How large is the inside dimension(s) of your chimney flue?

7" non corrugated (smooth interior) pipe may be fine at 7" but you can only go up to 325,000 BTU total on 7" corrugated liners at 35 feet hight with a short horizontal from the appliances inside the boiler room.