Help cleaning a plate heat exchanger

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Minister of Fire
Aug 22, 2010
Northern Canada
Hi All
As the leaves turn yellow and fall off the trees,it is time to get the boiler tuned up for winter.
I have been thinking that i should clean my heat exchanger.
It's been 13 years or so since i installed it.I have a sidestream filter plus a wye trap on the glycol side,and a wye trap on the water side.
It's a closed system,water was filtered prior to filling the storage.
I don't have any signs of issues,but i have an oversized exchanger.I do have it plumbed with shutoff valves and drain spigots at each opening.
I am looking for advice on a product to use for internal cleaning of the HX,and how long to circulate it through the HX.
Thanks in advance
I just use cleaning vinegar, let it circulate for an hour. Have even let it sit in exchanger for overnigh.
Sulfamic Acid works well for descaling.
I don't understand why you need to clean the water side of your system. If you have a closed system and don't keep replenishing water, the oxygen creating corrosion is gone a short time after the installation in a closed system. I have been using my Tarm MB55 Solo every year since 1980 and have never cleaned the water side once. The original water is in there now for 42 years. My boiler has worked trouble free since the day I put it in when I built my house in 1980.

My whole system is basically a standard heat pump with resistance backup (in case I "check out" before my wife) with a 2 row hot water coil that I sized and had installed above my air handler by the HVAC guys when I built my house in 1980. I have been using it for 42 years now (trouble free) and am extremely happy with it. The Emerald Ash Borer has helped me a lot in that I have a large amount of seasoned ash falling down waiting to be cut up. The ash wood is like "low hanging fruit", I don't even have to cut down the trees. Also, I have a 40 gallon "Amtrol Boiler Mate" that supplies all the hot water to my house when I have the MB55 in operation.

John M

P.S. I realize a lot of you guys on here think my system is trash--a "zero"--and out dated. You fellas will call my system a polluting "smoke dragon". I understand all that. All I know is that it is extremely simple and has absolutely no maintenance issues. I have replaced my Samson Draft Regulator once in 42 years. Also, once you get used to the heat load of your house, where the heat load on the boiler equals the heat loss of the house (vs. outdoor temp) you have a superb installation. It is very superior to my heat pump (for comfort in the house) which is controlled by a thermostat with a +/- 1 degree deadband. My wife loves it. When you match the heat input to the heat output, there is a constant temperature inside the house. This the ideal comfort solution.
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I was assuming that a cleaning once in a while would be a good maintenance item.