Holly vented wall heater thermostat

Old 04-08-15, 05:09 PM
Thread Starter
Join Date: Apr 2015
Posts: 1
Upvotes: 0
Received 0 Upvotes on 0 Posts
Holly vented wall heater thermostat

I have an old holly vented wall heater model 25 WS-WD and a similar double wall heater also holly vented. Lights up and heat.
Where is the thermostat? The knob has mark for low, medium and high but even if I keep it turned to the low it wont turn off, so I wonder if it has any thermostat or ...?
Name:  20150408_161630 k.jpg
Views: 3638
Size:  39.7 KB
Name:  20150408_161724 k.jpg
Views: 6313
Size:  40.3 KB
If it doesn't, can I install one and which model and how?
My son is a plumber.
Old 04-08-15, 05:58 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 65,136
Received 3,996 Upvotes on 3,586 Posts
Welcome to the forums.

I can find almost no information on that heater. It looks like Holly Heaters was a division of Lear Siegler at one time.

That type of heater didn't come with a thermostat and it is not designed to have a thermostat installed or attached to it.
Old 04-11-15, 07:53 PM
Join Date: Dec 2004
Location: San Jose,Ca
Posts: 1,277
Upvotes: 0
Received 3 Upvotes on 3 Posts
I've worked on many of that model. Pull the top grill off and look down inside at the heat exchanger. That is where they usually may have a crack. You can add a thermostat to the system, however all the old controls must be replaced which is quite expensive for an old furnace.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: