Latest Discussions : HVAC


01:35AM | 12/13/03
Member Since: 12/12/03
5 lifetime posts
I have a pretty old oil fired boiler that works well. The boiler also heats my hot water by way of these three good size units that screw in to the boiler, I think that makes it a tankless set-up. I have just purchased that house and my oil company tells me I need a new boiler. The heating units(coils ?) appear to have been replaced and the mixing valve looks new. What I have noticed is that whoever replaced the coils which are in series put one in backwards,They go in to out, in to out, and out to in. Could that be the problem ? I would appreciate any help, thanks.

plumber Tom

05:46AM | 12/13/03
Member Since: 05/10/03
801 lifetime posts
If there are directional water flow arrows it might make a difference. Your system is commomnly calles a summer-winter hook-up for hot water. Frequent hard water and calcium deposits get gunked up on the coils. Pull them out and clean them. With this type od configuration isolation valves are needed on the supply and return side of the boiler. Otherwise if no valves, then you have to drain the entire boiler down. If obvious maintenance (cleaning, flushing,etc. ) fails, then consider an indirect storage tank that can be tapped off your current boiler. might give you some insight. Happy Holiday's, Tom


11:35AM | 12/13/03
Member Since: 12/12/03
5 lifetime posts
Thanks a lot Tom,
Happy Holidays !


11:50AM | 12/14/03
Member Since: 12/09/03
175 lifetime posts
Getting to the hot water I hope it is sufficient. If not open the mixing valve up a little,also does this system have a seprate booster tank? If so check temperture controls 130 derees is good and that the circulator pump works. C.


04:15PM | 12/15/03
Member Since: 12/12/03
5 lifetime posts
I have experimented with the mixing valve adjustments without any success and all the hot water heating is done by the main boiler without any additional tanks or boosters . I am pretty sure the pressure problems are created by the blocked or incorrectly installed coils. I would need a massively large socket or wrench, in the 6 to 8 inch range with plenty of leverage to remove them. I am not sure where to locate such a tool.
Thanks for your input.


03:41AM | 12/20/03
Member Since: 12/12/03
5 lifetime posts
For the record, my problem turned out to be a clogged restrictor valve on the cold water side of the coils, I think. Does anyone know what the purpose of the valve is ? Why would you want to reduce the cold water flow ? Thanks.


01:20AM | 12/21/03
Member Since: 03/01/03
22 lifetime posts
I think you would want a constant flow in to get a constant temperature out...that's why the inlet flow restrictor. surges in flow would cause surges in hot water temp- ouch!!!


01:30AM | 12/24/03
Member Since: 12/12/03
5 lifetime posts
I think you're right, this boiler is way before the mixing valve era, thanks. Happy Holidays to you all !

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