weil mclain coil knock?

Anthony Menafro

Verify that the water temp. isn't too high at the high limit. Field check the temp. to make sure that the tridicator and aquastat are accurate.

Anthony Menafro

Bunsen

weil mclain coil knock?

Just had a new weil mclain wtgo-3 boiler installed. The tankless heater/coil has a knock or percolation sound. This has happen since new for almost a month now. This happens near the end of the cycle when heating water for the baseboard. It wont knock when drawing just for domestic but may get worse when using both. This noise can get bad upstairs as it reverberates. Installer has been back and a different service tech neither of which can find a cause. Both agree the sound is an overboil or some sort of water knock in the coil.This one has stumped the pros. Thanks for any help.

Guy_6

check

Is there a check valve in the domestic line to the tankless? If so, the water in the coil is expanding from the heat, yet has nowhere to expand to-check valve on one side, closed faucets on the other. It would explain why it doesn't happen when running domestic hot water,as there is a pressure break downstream. You said that it MAY get worse when both heat and hot water are running, but it seemed a bit unclear. If it is trapped pressure, an expansion tank on the domestic side should take care of it.

Weezbo

one picture would save a thousand words.

it is unlikely the coil ,recirculating (domestic) antiscald devise ,swing checks are... one or all piped correctly. i have heard shuddering noises from mixers for example,clanking noises from swing checks,...on and on...

went the long way around buh i trust you hear there can be a host of "Possible causes for similar "Noises"